LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 LM1575/LM2575/LM2575HV SIMPLE SWITCHER(R) 1A Step-Down Voltage Regulator Check for Samples: LM1575, LM2575-N, LM2575HV FEATURES DESCRIPTION * The LM2575 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 1A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, 15V, and an adjustable output version. 1 23 * * * * * * * * * * 3.3V, 5V, 12V, 15V, and Adjustable Output Versions Adjustable Version Output Voltage Range, - 1.23V to 37V (57V for HV Version) 4% Max Over - Line and Load Conditions Specified 1A Output Current Wide Input Voltage Range, 40V up to 60V for HV Version Requires Only 4 External Components 52 kHz Fixed Frequency Internal Oscillator TTL Shutdown Capability, Low Power Standby Mode High Efficiency Uses Readily Available Standard Inductors Thermal Shutdown and Current Limit Protection P+ Product Enhancement Tested APPLICATIONS * * * * Simple High-Efficiency Step-Down (Buck) Regulator Efficient Pre-Regulator for Linear Regulators On-Card Switching Regulators Positive to Negative Converter (Buck-Boost) Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation and a fixedfrequency oscillator. The LM2575 series offers a high-efficiency replacement for popular three-terminal linear regulators. It substantially reduces the size of the heat sink, and in many cases no heat sink is required. A standard series of inductors optimized for use with the LM2575 are available from several different manufacturers. This feature greatly simplifies the design of switch-mode power supplies. Other features include a specified 4% tolerance on output voltage within specified input voltages and output load conditions, and 10% on the oscillator frequency. External shutdown is included, featuring 50 A (typical) standby current. The output switch includes cycle-by-cycle current limiting, as well as thermal shutdown for full protection under fault conditions. Typical Application (Fixed Output Voltage Versions) Pin numbers are for the TO-220 package. 1 2 3 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. SIMPLE SWITCHER is a registered trademark of Texas Instruments. All other trademarks are the property of their respective owners. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright (c) 1999-2013, Texas Instruments Incorporated LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com Block Diagram and Typical Application 3.3V, R2 = 1.7k 5V, R2 = 3.1k 12V, R2 = 8.84k 15V, R2 = 11.3k For ADJ. Version R1 = Open, R2 = 0 Pin numbers are for the TO-220 package. Figure 1. 2 Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 Connection Diagrams (XX indicates output voltage option.) Top View Top View Figure 2. Straight Leads 5-Lead TO-220 Package LM2575T-XX or LM2575HVT-XX See Package Number KC0005A Figure 3. Bent, Staggered Leads 5-Lead TO-220 Package See Package Number NDH0005D Side View Figure 4. LM2575T-XX Flow LB03 or LM2575HVT-XX Flow LB03 See Package Number NDH0005D Top View Top View *No Internal Connection *No Internal Connection Figure 5. 16-Lead CDIP and PDIP Packages LM2575N-XX or LM2575HVN-XX LM1575J-XX-QML See Package Numbers NFE0016A and NBG Figure 6. 24-Lead Surface Mount SOIC Package LM2575M-XX or LM2575HVM-XX See Package Number DW0024B Top View Figure 7. DDPAK/TO-263 Package 5-Lead Surface-Mount Package See Package Number KTT0005B Side View Figure 8. LM2575S-XX or LM2575HVS-XX See Package Number KTT0005B Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback 3 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. ABSOLUTE MAXIMUM RATINGS (1) (2) (3) Maximum Supply Voltage LM1575/LM2575 45V LM2575HV 63V -0.3V V +VIN ON /OFF Pin Input Voltage Output Voltage to Ground -1V (Steady State) Power Dissipation Internally Limited Storage Temperature Range -65C to +150C Maximum Junction Temperature 150C Minimum ESD Rating (C = 100 pF, R = 1.5 k) Lead Temperature (Soldering, 10 sec.) (1) (2) (3) 2 kV 260C Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but do not ensure specific performance limits. For specified specifications and test conditions, see Electrical Characteristics. If Military/Aerospace specified devices are required, please contact the TI Sales Office/ Distributors for availability and specifications. Refer to RETS LM1575J for current revision of military RETS/SMD. OPERATING RATINGS Temperature Range Supply Voltage LM1575 -55C TJ +150C LM2575/LM2575HV -40C TJ +125C LM1575/LM2575 40V LM2575HV 60V ELECTRICAL CHARACTERISTICS LM1575-3.3, LM2575-3.3, LM2575HV-3.3 Specifications with standard type face are for TJ = 25C, and those with boldface type apply over full Operating Temperature Range . Symbol Parameter Conditions Typ LM1575-3.3 Limit SYSTEM PARAMETERS Test Circuit Figure 25 and Figure 26 VOUT VOUT VOUT (1) (2) (3) 4 Output Voltage Output Voltage LM1575/LM2575 Output Voltage LM2575HV Efficiency Limit (2) Units (Limits) (3) VIN = 12V, ILOAD = 0.2A Circuit Figure 25 and Figure 26 4.75V VIN 40V, 0.2A ILOAD 1A Circuit Figure 25 and Figure 26 4.75V VIN 60V, 0.2A ILOAD 1A Circuit Figure 25 and Figure 26 VIN = 12V, ILOAD = 1A (1) LM2575-3.3 LM2575HV-3.3 3.3 V 3.267 3.234 V(Min) 3.333 3.366 V(Max) 3.200/3.168 3.168/3.135 V(Min) 3.400/3.432 3.432/3.465 V(Max) 3.200/3.168 3.168/3.135 V(Min) 3.416/3.450 3.450/3.482 V(Max) 3.3 V 3.3 V 75 % All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to calculate Average Outgoing Quality Level, and all are 100% production tested. All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control (SQC) methods. External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance. When the LM1575/LM2575 is used as shown in the test circuit Figure 25 and Figure 26, system performance will be as shown in system parameters of Electrical Characteristics. Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 ELECTRICAL CHARACTERISTICS LM1575-5.0, LM2575-5.0, LM2575HV-5.0 Specifications with standard type face are for TJ = 25C, and those with boldface type apply over full Operating Temperature Range. Symbol Parameter Conditions Typ LM1575-5.0 Limit (1) LM2575-5.0 LM2575HV-5.0 Limit (2) Units (Limits) SYSTEM PARAMETERS Test Circuit Figure 25 and Figure 26 (3) VOUT VOUT VOUT (1) (2) (3) Output Voltage VIN = 12V, ILOAD = 0.2A Circuit Figure 25 and Figure 26 5.0 Output Voltage LM1575/LM2575 0.2A ILOAD 1A, 8V VIN 40V Circuit Figure 25 and Figure 26 5.0 Output Voltage LM2575HV 0.2A ILOAD 1A, 8V VIN 60V Circuit Figure 25 and Figure 26 5.0 Efficiency VIN = 12V, ILOAD = 1A 77 V 4.950 4.900 V(Min) 5.050 5.100 V(Max) 4.850/4.800 4.800/4.750 V(Min) 5.150/5.200 5.200/5.250 V(Max) 4.850/4.800 4.800/4.750 V(Min) 5.175/5.225 5.225/5.275 V(Max) V V % All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to calculate Average Outgoing Quality Level, and all are 100% production tested. All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control (SQC) methods. External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance. When the LM1575/LM2575 is used as shown in the test circuit Figure 25 and Figure 26, system performance will be as shown in system parameters of Electrical Characteristics. ELECTRICAL CHARACTERISTICS LM1575-12, LM2575-12, LM2575HV-12 Specifications with standard type face are for TJ = 25C, and those with boldface type apply over full Operating Temperature Range . Symbol Parameter Conditions Typ LM1575-12 Limit SYSTEM PARAMETERS Test Circuit Figure 25 and Figure 26 VOUT VOUT VOUT (1) (2) (3) Output Voltage Output Voltage LM1575/LM2575 (1) LM2575-12 LM2575HV-12 Limit (2) Units (Limits) (3) VIN = 25V, ILOAD = 0.2A Circuit Figure 25 and Figure 26 0.2A ILOAD 1A, 15V VIN 40V Circuit Figure 25 and Figure 26 12 V 11.88 11.76 V(Min) 12.12 12.24 V(Max) 12 Output Voltage LM2575HV 0.2A ILOAD 1A, 15V VIN 60V Circuit Figure 25 and Figure 26 12 Efficiency VIN = 15V, ILOAD = 1A 88 V 11.64/11.52 11.52/11.40 V(Min) 12.36/12.48 12.48/12.60 V(Max) 11.64/11.52 11.52/11.40 V(Min) 12.42/12.54 12.54/12.66 V(Max) V % All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to calculate Average Outgoing Quality Level, and all are 100% production tested. All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control (SQC) methods. External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance. When the LM1575/LM2575 is used as shown in the test circuit Figure 25 and Figure 26, system performance will be as shown in system parameters of Electrical Characteristics. Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback 5 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com ELECTRICAL CHARACTERISTICS LM1575-15, LM2575-15, LM2575HV-15 Specifications with standard type face are for TJ = 25C, and those with boldface type apply over full Operating Temperature Range . Parameter Conditions LM1575-15 Typ Symbol Limit (1) LM2575-15 LM2575HV-15 Limit (2) Units (Limits) SYSTEM PARAMETERS Test Circuit Figure 25 and Figure 26 (3) VOUT Output Voltage VOUT VOUT (1) (2) (3) VIN = 30V, ILOAD = 0.2A Circuit Figure 25 and Figure 26 15 Output Voltage LM1575/LM2575 0.2A ILOAD 1A, 18V VIN 40V Circuit Figure 25 and Figure 26 15 Output Voltage LM2575HV 0.2A ILOAD 1A, 18V VIN 60V Circuit Figure 25 and Figure 26 15 Efficiency VIN = 18V, ILOAD = 1A 88 V 14.85 14.70 V(Min) 15.15 15.30 V(Max) 14.55/14.40 14.40/14.25 V(Min) 15.45/15.60 15.60/15.75 V(Max) 14.55/14.40 14.40/14.25 V(Min) 15.525/15.675 15.68/15.83 V(Max) V V % All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to calculate Average Outgoing Quality Level, and all are 100% production tested. All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control (SQC) methods. External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance. When the LM1575/LM2575 is used as shown in the test circuit Figure 25 and Figure 26, system performance will be as shown in system parameters of Electrical Characteristics. ELECTRICAL CHARACTERISTICS LM1575-ADJ, LM2575-ADJ, LM2575HV-ADJ Specifications with standard type face are for TJ= 25C, and those with boldface type apply over full Operating Temperature Range. Symbol Parameter Conditions Typ LM1575-ADJ Limit (1) LM2575-ADJ LM2575HV-ADJ Limit (2) Units (Limits) SYSTEM PARAMETERS Test Circuit Figure 25 and Figure 26 (3) VOUT VOUT VOUT (1) (2) (3) 6 Feedback Voltage Feedback Voltage LM1575/LM2575 Feedback Voltage LM2575HV Efficiency VIN = 12V, ILOAD = 0.2A VOUT = 5V Circuit Figure 25 and Figure 26 1.230 0.2A ILOAD 1A, 8V VIN 40V VOUT = 5V, Circuit Figure 25 and Figure 26 1.230 0.2A ILOAD 1A, 8V VIN 60V VOUT = 5V, Circuit Figure 25 and Figure 26 1.230 VIN = 12V, ILOAD = 1A, VOUT = 5V 77 V 1.217 1.217 V(Min) 1.243 1.243 V(Max) V 1.205/1.193 1.193/1.180 V(Min) 1.255/1.267 1.267/1.280 V(Max) V 1.205/1.193 1.193/1.180 V(Min) 1.261/1.273 1.273/1.286 V(Max) % All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to calculate Average Outgoing Quality Level, and all are 100% production tested. All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control (SQC) methods. External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance. When the LM1575/LM2575 is used as shown in the test circuit Figure 25 and Figure 26, system performance will be as shown in system parameters of Electrical Characteristics. Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 ELECTRICAL CHARACTERISTICS ALL OUTPUT VOLTAGE VERSIONS Specifications with standard type face are for TJ = 25C, and those with boldface type apply over full Operating Temperature Range. Unless otherwise specified, VIN = 12V for the 3.3V, 5V, and Adjustable version, VIN = 25V for the 12V version, and VIN = 30V for the 15V version. ILOAD = 200 mA. Symbol Parameter Conditions Typ LM1575-XX Limit (1) LM2575-XX LM2575HV-XX Limit (2) Units (Limits) DEVICE PARAMETERS Ib Feedback Bias Current VOUT = 5V (Adjustable Version Only) fO Oscillator Frequency See VSAT DC ICL IL IQ ISTBY JA JA JC JA JA JA Saturation Voltage Max Duty Cycle (ON) Current Limit (3) IOUT = 1A See 100/500 100/500 nA 52 (4) Peak Current Output Leakage Current Output = 0V Output = -1V Output = -1V Quiescent Current See kHz 47/43 47/42 kHz(Min) 58/62 58/63 kHz(Max) 1.2/1.4 1.2/1.4 V(Max) 93 93 %(Min) 0.9 (5) V 98 (4) (3) (6) (7) (6) Standby Quiescent Current ON /OFF Pin = 5V (OFF) Thermal Resistance TO-220 Package, Junction to Ambient (8) TO-220 Package, Junction to Ambient (9) TO-220 Package, Junction to Case CDIP Package, Junction to Ambient (10) SOIC Package, Junction to Ambient (10) DDPAK/TO-263 Package, Junction to Ambient (11) 50 % 2.2 A 1.7/1.3 1.7/1.3 A(Min) 3.0/3.2 3.0/3.2 A(Max) 2 2 mA(Max) 7.5 mA 30 30 mA(Max) 10/12 10 mA(Max) 200/500 200 A(Max) 5 mA A 50 65 45 2 85 100 37 C/W (1) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All limits are used to calculate Average Outgoing Quality Level, and all are 100% production tested. (2) All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control (SQC) methods. (3) The oscillator frequency reduces to approximately 18 kHz in the event of an output short or an overload which causes the regulated output voltage to drop approximately 40% from the nominal output voltage. This self protection feature lowers the average power dissipation of the IC by lowering the minimum duty cycle from 5% down to approximately 2%. (4) Output (pin 2) sourcing current. No diode, inductor or capacitor connected to output pin. (5) Feedback (pin 4) removed from output and connected to 0V. (6) Feedback (pin 4) removed from output and connected to +12V for the Adjustable, 3.3V, and 5V versions, and +25V for the 12V and 15V versions, to force the output transistor OFF. (7) VIN = 40V (60V for the high voltage version). (8) Junction to ambient thermal resistance (no external heat sink) for the 5 lead TO-220 package mounted vertically, with 1/2 inch leads in a socket, or on a PC board with minimum copper area. (9) Junction to ambient thermal resistance (no external heat sink) for the 5 lead TO-220 package mounted vertically, with 1/2 inch leads soldered to a PC board containing approximately 4 square inches of copper area surrounding the leads. (10) Junction to ambient thermal resistance with approximately 1 square inch of pc board copper surrounding the leads. Additional copper area will lower thermal resistance further. See thermal model in Switchers made Simple software. (11) If the DDPAK/TO-263 package is used, the thermal resistance can be reduced by increasing the PC board copper area thermally connected to the package: Using 0.5 square inches of copper area, JA is 50C/W; with 1 square inch of copper area, JA is 37C/W; and with 1.6 or more square inches of copper area, JA is 32C/W. Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback 7 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com ELECTRICAL CHARACTERISTICS ALL OUTPUT VOLTAGE VERSIONS (continued) Specifications with standard type face are for TJ = 25C, and those with boldface type apply over full Operating Temperature Range. Unless otherwise specified, VIN = 12V for the 3.3V, 5V, and Adjustable version, VIN = 25V for the 12V version, and VIN = 30V for the 15V version. ILOAD = 200 mA. Symbol Parameter Conditions Typ LM1575-XX Limit (1) LM2575-XX LM2575HV-XX Limit (2) Units (Limits) ON /OFF CONTROL Test Circuit Figure 25 and Figure 26 VIH VIL IIH IIL 8 ON /OFF Pin Logic Input Level VOUT = 0V 1.4 2.2/2.4 2.2/2.4 V(Min) VOUT = Nominal Output Voltage 1.2 1.0/0.8 1.0/0.8 V(Max) ON /OFF Pin Input Current ON /OFF Pin = 5V (OFF) 12 ON /OFF Pin = 0V (ON) 0 Submit Documentation Feedback A 30 30 A(Max) 10 10 A(Max) A Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 TYPICAL PERFORMANCE CHARACTERISTICS (Circuit Figure 25 and Figure 26) Normalized Output Voltage Line Regulation Figure 9. Figure 10. Dropout Voltage Current Limit Figure 11. Figure 12. Quiescent Current Standby Quiescent Current Figure 13. Figure 14. Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback 9 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com TYPICAL PERFORMANCE CHARACTERISTICS (continued) (Circuit Figure 25 and Figure 26) 10 Oscillator Frequency Switch Saturation Voltage Figure 15. Figure 16. Efficiency Minimum Operating Voltage Figure 17. Figure 18. Quiescent Current vs Duty Cycle Feedback Voltage vs Duty Cycle Figure 19. Figure 20. Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 TYPICAL PERFORMANCE CHARACTERISTICS (continued) (Circuit Figure 25 and Figure 26) Feedback Pin Current Maximum Power Dissipation (TO-263) (See (1)) Figure 21. Figure 22. Switching Waveforms Load Transient Response VOUT = 5V A: Output Pin Voltage, 10V/div B: Output Pin Current, 1A/div C: Inductor Current, 0.5A/div D: Output Ripple Voltage, 20 mV/div, AC-Coupled Horizontal Time Base: 5 s/div Figure 23. (1) Figure 24. If the DDPAK/TO-263 package is used, the thermal resistance can be reduced by increasing the PC board copper area thermally connected to the package: Using 0.5 square inches of copper area, JA is 50C/W; with 1 square inch of copper area, JA is 37C/W; and with 1.6 or more square inches of copper area, JA is 32C/W. Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback 11 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com TEST CIRCUIT AND LAYOUT GUIDELINES As in any switching regulator, layout is very important. Rapidly switching currents associated with wiring inductance generate voltage transients which can cause problems. For minimal inductance and ground loops, the length of the leads indicated by heavy lines should be kept as short as possible. Single-point grounding (as indicated) or ground plane construction should be used for best results. When using the Adjustable version, physically locate the programming resistors near the regulator, to keep the sensitive feedback wiring short. CIN -- 100 F, 75V, Aluminum Electrolytic COUT -- 330 F, 25V, Aluminum Electrolytic D1 -- Schottky, 11DQ06 L1 -- 330 H, PE-52627 (for 5V in, 3.3V out, use 100 H, PE-92108) Figure 25. Fixed Output Voltage Versions where VREF = 1.23V, R1 between 1k and 5k. R1 -- 2k, 0.1% R2 -- 6.12k, 0.1% Pin numbers are for the TO-220 package. Figure 26. Adjustable Output Voltage Version 12 Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 LM2575 Series Buck Regulator Design Procedure PROCEDURE (Fixed Output Voltage Versions) Given: VIN(Max) = Maximum Input Voltage VOUT = Regulated Output Voltage (3.3V, 5V, 12V, or 15V) ILOAD(Max) = Maximum Load Current 1. Inductor Selection (L1) A. Select the correct Inductor value selection guide from Figure 27, Figure 28, Figure 29 and Figure 30 (Output voltages of 3.3V, 5V, 12V or 15V respectively). For other output voltages, see the design procedure of Figure 26 . B. From the inductor value selection guide, identify the inductance region intersected by VIN(Max) and ILOAD(Max), and note the inductor code for that region. C. Identify the inductor value from the inductor code, and select an appropriate inductor from the table shown in Table 2. Part numbers are listed for three inductor manufacturers. The inductor chosen must be rated for operation at the LM2575 switching frequency (52 kHz) and for a current rating of 1.15 x ILOAD. For additional inductor information, see INDUCTOR SELECTION. EXAMPLE (Fixed Output Voltage Versions) Given: VOUT = 5V VIN(Max) = 20V ILOAD(Max) = 0.8A 1. Inductor Selection (L1) A. Use the selection guide shown in Figure 28. B. From the selection guide, the inductance area intersected by the 20V line and 0.8A line is L330. C. Inductor value required is 330 H. From the table in Table 2, choose AIE 415-0926, Pulse Engineering PE-52627, or RL1952. 2. Output Capacitor Selection (COUT) 2. Output Capacitor Selection (COUT) A. The value of the output capacitor together with the inductor A. COUT = 100 F to 470 F standard aluminum electrolytic. defines the dominate pole-pair of the switching regulator loop. For B. Capacitor voltage rating = 20V. stable operation and an acceptable output ripple voltage, (approximately 1% of the output voltage) a value between 100 F and 470 F is recommended. B. The capacitor's voltage rating should be at least 1.5 times greater than the output voltage. For a 5V regulator, a rating of at least 8V is appropriate, and a 10V or 15V rating is recommended. Higher voltage electrolytic capacitors generally have lower ESR numbers, and for this reason it may be necessary to select a capacitor rated for a higher voltage than would normally be needed. 3. Catch Diode Selection (D1) A. The catch-diode current rating must be at least 1.2 times greater than the maximum load current. Also, if the power supply design must withstand a continuous output short, the diode should have a current rating equal to the maximum current limit of the LM2575. The most stressful condition for this diode is an overload or shorted output condition. B. The reverse voltage rating of the diode should be at least 1.25 times the maximum input voltage. 3. Catch Diode Selection (D1) A. For this example, a 1A current rating is adequate. B. Use a 30V 1N5818 or SR103 Schottky diode, or any of the suggested fast-recovery diodes shown in Table 1. 4. Input Capacitor (CIN) 4. Input Capacitor (CIN) An aluminum or tantalum electrolytic bypass capacitor located close A 47 F, 25V aluminum electrolytic capacitor located near the input to the regulator is needed for stable operation. and ground pins provides sufficient bypassing. Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback 13 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com Inductor Value Selection Guides (For Continuous Mode Operation) Figure 27. LM2575(HV)-3.3 Figure 28. LM2575(HV)-5.0 Figure 29. LM2575(HV)-12 Figure 30. LM2575(HV)-15 Figure 31. LM2575(HV)-ADJ 14 Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 PROCEDURE (Adjustable Output Voltage Versions) EXAMPLE (Adjustable Output Voltage Versions) Given: VOUT = Regulated Output Voltage VIN(Max) = Maximum Input Voltage ILOAD(Max) = Maximum Load Current F = Switching Frequency (Fixed at 52 kHz) Given: VOUT = 10V VIN(Max) = 25V ILOAD(Max) = 1A F = 52 kHz 1. Programming Output Voltage (Selecting R1 and R2, as shown 1. Programming Output Voltage (Selecting R1 and R2) in Figure 25 and Figure 26) Use the following formula to select the appropriate resistor values. (1) R1 can be between 1k and 5k. (For best temperature coefficient and R2 = 1k (8.13 - 1) = 7.13k, closest 1% value is 7.15k stability with time, use 1% metal film resistors) (3) (2) 2. Inductor Selection (L1) A. Calculate the inductor Volt * microsecond constant, E * T (V * s), from the following formula: 2. Inductor Selection (L1) A. Calculate E * T (V * s) (5) (4) B. E * T = 115 V * s B. Use the E * T value from the previous formula and match it with the E * T number on the vertical axis of the Inductor Value Selection Guide shown in Figure 31. C. On the horizontal axis, select the maximum load current. D. Identify the inductance region intersected by the E * T value and the maximum load current value, and note the inductor code for that region. E. Identify the inductor value from the inductor code, and select an appropriate inductor from the table shown in Table 2. Part numbers are listed for three inductor manufacturers. The inductor chosen must be rated for operation at the LM2575 switching frequency (52 kHz) and for a current rating of 1.15 x ILOAD. For additional inductor information, see INDUCTOR SELECTION. C. ILOAD(Max) = 1A D. Inductance Region = H470 E. Inductor Value = 470 H Choose from AIE part #430-0634, Pulse Engineering part #PE-53118, or Renco part #RL-1961. 3. Output Capacitor Selection (COUT) 3. Output Capacitor Selection (COUT) A. The value of the output capacitor together with the inductor A. defines the dominate pole-pair of the switching regulator loop. For stable operation, the capacitor must satisfy the following requirement: However, for acceptable output ripple voltage select C 220 F (6) OUT COUT = 220 F electrolytic capacitor The above formula yields capacitor values between 10 F and 2000 F that will satisfy the loop requirements for stable operation. But to achieve an acceptable output ripple voltage, (approximately 1% of the output voltage) and transient response, the output capacitor may need to be several times larger than the above formula yields. B. The capacitor's voltage rating should be at last 1.5 times greater than the output voltage. For a 10V regulator, a rating of at least 15V or more is recommended. Higher voltage electrolytic capacitors generally have lower ESR numbers, and for this reason it may be necessary to select a capacitor rate for a higher voltage than would normally be needed. (Continued) (7) (Continued) Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback 15 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com PROCEDURE (Adjustable Output Voltage Versions) EXAMPLE (Adjustable Output Voltage Versions) 4. Catch Diode Selection (D1) A. The catch-diode current rating must be at least 1.2 times greater than the maximum load current. Also, if the power supply design must withstand a continuous output short, the diode should have a current rating equal to the maximum current limit of the LM2575. The most stressful condition for this diode is an overload or shorted output. See Table 1. B. The reverse voltage rating of the diode should be at least 1.25 times the maximum input voltage. 4. Catch Diode Selection (D1) A. For this example, a 3A current rating is adequate. B. Use a 40V MBR340 or 31DQ04 Schottky diode, or any of the suggested fast-recovery diodes in Table 1. 5. Input Capacitor (CIN) 5. Input Capacitor (CIN) An aluminum or tantalum electrolytic bypass capacitor located close A 100 F aluminum electrolytic capacitor located near the input and to the regulator is needed for stable operation. ground pins provides sufficient bypassing. To further simplify the buck regulator design procedure, TI is making available computer design software to be used with the Simple Switcher line of switching regulators. Switchers Made Simple (version 3.3) is available on a (31/2) diskette for IBM compatible computers from a TI sales office in your area. Table 1. Diode Selection Guide Schottky VR 1A Fast Recovery 3A 20V 1N5817 MBR120P SR102 1N5820 MBR320 SR302 30V 1N5818 MBR130P 11DQ03 SR103 1N5821 MBR330 31DQ03 SR303 40V 1N5819 MBR140P 11DQ04 SR104 IN5822 MBR340 31DQ04 SR304 50V MBR150 11DQ05 SR105 MBR350 31DQ05 SR305 60V MBR160 11DQ06 SR106 MBR360 31DQ06 SR306 1A 3A The following The following diodes are all diodes are all rated to 100V: rated to 100V: 11DF1 MUR110 HER102 31DF1 MURD310 HER302 Table 2. Inductor Selection by Manufacturer's Part Number (1) (2) (3) 16 Schott (1) Pulse Eng. (2) Renco (3) Inductor Code Inductor Value L100 100 H 67127000 PE-92108 RL2444 L150 150 H 67127010 PE-53113 RL1954 L220 220 H 67127020 PE-52626 RL1953 L330 330 H 67127030 PE-52627 RL1952 L470 470 H 67127040 PE-53114 RL1951 L680 680 H 67127050 PE-52629 RL1950 H150 150 H 67127060 PE-53115 RL2445 H220 220 H 67127070 PE-53116 RL2446 H330 330 H 67127080 PE-53117 RL2447 H470 470 H 67127090 PE-53118 RL1961 H680 680 H 67127100 PE-53119 RL1960 H1000 1000 H 67127110 PE-53120 RL1959 Schott Corp., (612) 475-1173, 1000 Parkers Lake Rd., Wayzata, MN 55391. Pulse Engineering, (619) 674-8100, P.O. Box 12236, San Diego, CA 92112. Renco Electronics Inc., (516) 586-5566, 60 Jeffryn Blvd. East, Deer Park, NY 11729. Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 Table 2. Inductor Selection by Manufacturer's Part Number (continued) Schott (1) Pulse Eng. (2) Renco (3) Inductor Code Inductor Value H1500 1500 H 67127120 PE-53121 RL1958 H2200 2200 H 67127130 PE-53122 RL2448 APPLICATION HINTS INPUT CAPACITOR (CIN) To maintain stability, the regulator input pin must be bypassed with at least a 47 F electrolytic capacitor. The capacitor's leads must be kept short, and located near the regulator. If the operating temperature range includes temperatures below -25C, the input capacitor value may need to be larger. With most electrolytic capacitors, the capacitance value decreases and the ESR increases with lower temperatures and age. Paralleling a ceramic or solid tantalum capacitor will increase the regulator stability at cold temperatures. For maximum capacitor operating lifetime, the capacitor's RMS ripple current rating should be greater than (8) INDUCTOR SELECTION All switching regulators have two basic modes of operation: continuous and discontinuous. The difference between the two types relates to the inductor current, whether it is flowing continuously, or if it drops to zero for a period of time in the normal switching cycle. Each mode has distinctively different operating characteristics, which can affect the regulator performance and requirements. The LM2575 (or any of the Simple Switcher family) can be used for both continuous and discontinuous modes of operation. The inductor value selection guides in Figure 27 through Figure 31 were designed for buck regulator designs of the continuous inductor current type. When using inductor values shown in the inductor selection guide, the peak-to-peak inductor ripple current will be approximately 20% to 30% of the maximum DC current. With relatively heavy load currents, the circuit operates in the continuous mode (inductor current always flowing), but under light load conditions, the circuit will be forced to the discontinuous mode (inductor current falls to zero for a period of time). This discontinuous mode of operation is perfectly acceptable. For light loads (less than approximately 200 mA) it may be desirable to operate the regulator in the discontinuous mode, primarily because of the lower inductor values required for the discontinuous mode. The selection guide chooses inductor values suitable for continuous mode operation, but if the inductor value chosen is prohibitively high, the designer should investigate the possibility of discontinuous operation. The computer design software Switchers Made Simple will provide all component values for discontinuous (as well as continuous) mode of operation. Inductors are available in different styles such as pot core, toriod, E-frame, bobbin core, etc., as well as different core materials, such as ferrites and powdered iron. The least expensive, the bobbin core type, consists of wire wrapped on a ferrite rod core. This type of construction makes for an inexpensive inductor, but since the magnetic flux is not completely contained within the core, it generates more electromagnetic interference (EMI). This EMI can cause problems in sensitive circuits, or can give incorrect scope readings because of induced voltages in the scope probe. The inductors listed in the selection chart include ferrite pot core construction for AIE, powdered iron toroid for Pulse Engineering, and ferrite bobbin core for Renco. Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback 17 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com An inductor should not be operated beyond its maximum rated current because it may saturate. When an inductor begins to saturate, the inductance decreases rapidly and the inductor begins to look mainly resistive (the DC resistance of the winding). This will cause the switch current to rise very rapidly. Different inductor types have different saturation characteristics, and this should be kept in mind when selecting an inductor. The inductor manufacturer's data sheets include current and energy limits to avoid inductor saturation. INDUCTOR RIPPLE CURRENT When the switcher is operating in the continuous mode, the inductor current waveform ranges from a triangular to a sawtooth type of waveform (depending on the input voltage). For a given input voltage and output voltage, the peak-to-peak amplitude of this inductor current waveform remains constant. As the load current rises or falls, the entire sawtooth current waveform also rises or falls. The average DC value of this waveform is equal to the DC load current (in the buck regulator configuration). If the load current drops to a low enough level, the bottom of the sawtooth current waveform will reach zero, and the switcher will change to a discontinuous mode of operation. This is a perfectly acceptable mode of operation. Any buck switching regulator (no matter how large the inductor value is) will be forced to run discontinuous if the load current is light enough. OUTPUT CAPACITOR An output capacitor is required to filter the output voltage and is needed for loop stability. The capacitor should be located near the LM2575 using short pc board traces. Standard aluminum electrolytics are usually adequate, but low ESR types are recommended for low output ripple voltage and good stability. The ESR of a capacitor depends on many factors, some which are: the value, the voltage rating, physical size and the type of construction. In general, low value or low voltage (less than 12V) electrolytic capacitors usually have higher ESR numbers. The amount of output ripple voltage is primarily a function of the ESR (Equivalent Series Resistance) of the output capacitor and the amplitude of the inductor ripple current (IIND). (See INDUCTOR RIPPLE CURRENT). The lower capacitor values (220 F-680 F) will allow typically 50 mV to 150 mV of output ripple voltage, while larger-value capacitors will reduce the ripple to approximately 20 mV to 50 mV. Output Ripple Voltage = (IIND) (ESR of COUT) (9) To further reduce the output ripple voltage, several standard electrolytic capacitors may be paralleled, or a higher-grade capacitor may be used. Such capacitors are often called "high-frequency," "low-inductance," or "low-ESR." These will reduce the output ripple to 10 mV or 20 mV. However, when operating in the continuous mode, reducing the ESR below 0.05 can cause instability in the regulator. Tantalum capacitors can have a very low ESR, and should be carefully evaluated if it is the only output capacitor. Because of their good low temperature characteristics, a tantalum can be used in parallel with aluminum electrolytics, with the tantalum making up 10% or 20% of the total capacitance. The capacitor's ripple current rating at 52 kHz should be at least 50% higher than the peak-to-peak inductor ripple current. CATCH DIODE Buck regulators require a diode to provide a return path for the inductor current when the switch is off. This diode should be located close to the LM2575 using short leads and short printed circuit traces. Because of their fast switching speed and low forward voltage drop, Schottky diodes provide the best efficiency, especially in low output voltage switching regulators (less than 5V). Fast-Recovery, High-Efficiency, or Ultra-Fast Recovery diodes are also suitable, but some types with an abrupt turn-off characteristic may cause instability and EMI problems. A fast-recovery diode with soft recovery characteristics is a better choice. Standard 60 Hz diodes (example: 1N4001 or 1N5400, and so on.) are also not suitable. See Table 1 for Schottky and "soft" fastrecovery diode selection guide. 18 Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 OUTPUT VOLTAGE RIPPLE AND TRANSIENTS The output voltage of a switching power supply will contain a sawtooth ripple voltage at the switcher frequency, typically about 1% of the output voltage, and may also contain short voltage spikes at the peaks of the sawtooth waveform. The output ripple voltage is due mainly to the inductor sawtooth ripple current multiplied by the ESR of the output capacitor. (See INDUCTOR SELECTION) The voltage spikes are present because of the fast switching action of the output switch, and the parasitic inductance of the output filter capacitor. To minimize these voltage spikes, special low inductance capacitors can be used, and their lead lengths must be kept short. Wiring inductance, stray capacitance, as well as the scope probe used to evaluate these transients, all contribute to the amplitude of these spikes. An additional small LC filter (20 H & 100 F) can be added to the output (as shown in Figure 37) to further reduce the amount of output ripple and transients. A 10 x reduction in output ripple voltage and transients is possible with this filter. FEEDBACK CONNECTION The LM2575 (fixed voltage versions) feedback pin must be wired to the output voltage point of the switching power supply. When using the adjustable version, physically locate both output voltage programming resistors near the LM2575 to avoid picking up unwanted noise. Avoid using resistors greater than 100 k because of the increased chance of noise pickup. ON /OFF INPUT For normal operation, the ON /OFF pin should be grounded or driven with a low-level TTL voltage (typically below 1.6V). To put the regulator into standby mode, drive this pin with a high-level TTL or CMOS signal. The ON /OFF pin can be safely pulled up to +VIN without a resistor in series with it. The ON /OFF pin should not be left open. GROUNDING To maintain output voltage stability, the power ground connections must be low-impedance (see Figure 26). For the TO-3 style package, the case is ground. For the 5-lead TO-220 style package, both the tab and pin 3 are ground and either connection may be used, as they are both part of the same copper lead frame. With the CDIP or SOIC packages, all the pins labeled ground, power ground, or signal ground should be soldered directly to wide printed circuit board copper traces. This assures both low inductance connections and good thermal properties. HEAT SINK/THERMAL CONSIDERATIONS In many cases, no heat sink is required to keep the LM2575 junction temperature within the allowed operating range. For each application, to determine whether or not a heat sink will be required, the following must be identified: 1. Maximum ambient temperature (in the application). 2. Maximum regulator power dissipation (in application). 3. Maximum allowed junction temperature (150C for the LM1575 or 125C for the LM2575). For a safe, conservative design, a temperature approximately 15C cooler than the maximum temperature should be selected. 4. LM2575 package thermal resistances JA and JC. Total power dissipated by the LM2575 can be estimated as follows: PD = (VIN) (IQ) + (VO/VIN) (ILOAD) (VSAT) where * * * * IQ (quiescent current) and VSAT can be found in the Characteristic Curves shown previously, VIN is the applied minimum input voltage, VO is the regulated output voltage and ILOAD is the load current. Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback (10) 19 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com The dynamic losses during turn-on and turn-off are negligible if a Schottky type catch diode is used. When no heat sink is used, the junction temperature rise can be determined by the following: TJ = (PD) (JA) (11) To arrive at the actual operating junction temperature, add the junction temperature rise to the maximum ambient temperature. TJ = TJ + TA (12) If the actual operating junction temperature is greater than the selected safe operating junction temperature determined in step 3, then a heat sink is required. When using a heat sink, the junction temperature rise can be determined by the following: TJ = (PD) (JC + interface + Heat sink) (13) The operating junction temperature will be: TJ = TA + TJ (14) As shown in Equation 14, if the actual operating junction temperature is greater than the selected safe operating junction temperature, then a larger heat sink is required (one that has a lower thermal resistance). When using the LM2575 in the plastic CDIP or surface mount SOIC packages, several items about the thermal properties of the packages should be understood. The majority of the heat is conducted out of the package through the leads, with a minor portion through the plastic parts of the package. Since the lead frame is solid copper, heat from the die is readily conducted through the leads to the printed circuit board copper, which is acting as a heat sink. For best thermal performance, the ground pins and all the unconnected pins should be soldered to generous amounts of printed circuit board copper, such as a ground plane. Large areas of copper provide the best transfer of heat to the surrounding air. Copper on both sides of the board is also helpful in getting the heat away from the package, even if there is no direct copper contact between the two sides. Thermal resistance numbers as low as 40C/W for the SOIC package, and 30C/W for the CDIP package can be realized with a carefully engineered pc board. Included on the Switchers Made Simple design software is a more precise (non-linear) thermal model that can be used to determine junction temperature with different input-output parameters or different component values. It can also calculate the heat sink thermal resistance required to maintain the regulators junction temperature below the maximum operating temperature. ADDITIONAL APPLICATIONS INVERTING REGULATOR Figure 32 shows a LM2575-12 in a buck-boost configuration to generate a negative 12V output from a positive input voltage. This circuit bootstraps the regulator's ground pin to the negative output voltage, then by grounding the feedback pin, the regulator senses the inverted output voltage and regulates it to -12V. For an input voltage of 12V or more, the maximum available output current in this configuration is approximately 0.35A. At lighter loads, the minimum input voltage required drops to approximately 4.7V. The switch currents in this buck-boost configuration are higher than in the standard buck-mode design, thus lowering the available output current. Also, the start-up input current of the buck-boost converter is higher than the standard buck-mode regulator, and this may overload an input power source with a current limit less than 1.5A. Using a delayed turn-on or an undervoltage lockout circuit (described in the NEGATIVE BOOST REGULATOR section) would allow the input voltage to rise to a high enough level before the switcher would be allowed to turn on. Because of the structural differences between the buck and the buck-boost regulator topologies, the buck regulator design procedure section cannot be used to select the inductor or the output capacitor. The recommended range of inductor values for the buck-boost design is between 68 H and 220 H, and the output capacitor values must be larger than what is normally required for buck designs. Low input voltages or high output currents require a large value output capacitor (in the thousands of micro Farads). 20 Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 The peak inductor current, which is the same as the peak switch current, can be calculated from the following formula: where * fosc = 52 kHz. (15) Under normal continuous inductor current operating conditions, the minimum VIN represents the worst case. Select an inductor that is rated for the peak current anticipated. Also, the maximum voltage appearing across the regulator is the absolute sum of the input and output voltage. For a -12V output, the maximum input voltage for the LM2575 is +28V, or +48V for the LM2575HV. The Switchers Made Simple (version 3.3) design software can be used to determine the feasibility of regulator designs using different topologies, different input-output parameters, different components, and so on. Figure 32. Inverting Buck-Boost Develops -12V NEGATIVE BOOST REGULATOR Another variation on the buck-boost topology is the negative boost configuration. The circuit in Figure 33 accepts an input voltage ranging from -5V to -12V and provides a regulated -12V output. Input voltages greater than -12V will cause the output to rise above -12V, but will not damage the regulator. Because of the boosting function of this type of regulator, the switch current is relatively high, especially at low input voltages. Output load current limitations are a result of the maximum current rating of the switch. Also, boost regulators can not provide current limiting load protection in the event of a shorted load, so some other means (such as a fuse) may be necessary. Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback 21 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com + Feedback VIN 1 LM2575-12 4 Output Low ESR 2 + CIN 3 GND 5 ON/OFF COUT 1000 PF 1N5817 100 PF VOUT = -12V 150 PH -VIN -5V to -12V Typical Load Current 200 mA for VIN = -5.2V 500 mA for VIN = -7V Pin numbers are for TO-220 package. Figure 33. Negative Boost UNDERVOLTAGE LOCKOUT In some applications it is desirable to keep the regulator off until the input voltage reaches a certain threshold. An undervoltage lockout circuit which accomplishes this task is shown in Figure 34, while Figure 35 shows the same circuit applied to a buck-boost configuration. These circuits keep the regulator off until the input voltage reaches a predetermined level. VTH VZ1 + 2VBE (Q1) (16) DELAYED STARTUP The ON /OFF pin can be used to provide a delayed startup feature as shown in Figure 36. With an input voltage of 20V and for the part values shown, the circuit provides approximately 10 ms of delay time before the circuit begins switching. Increasing the RC time constant can provide longer delay times. But excessively large RC time constants can cause problems with input voltages that are high in 60 Hz or 120 Hz ripple, by coupling the ripple into the ON /OFF pin. ADJUSTABLE OUTPUT, LOW-RIPPLE POWER SUPPLY A 1A power supply that features an adjustable output voltage is shown in Figure 37. An additional L-C filter that reduces the output ripple by a factor of 10 or more is included in this circuit. 22 Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 Complete circuit not shown. Pin numbers are for the TO-220 package. Figure 34. Undervoltage Lockout for Buck Circuit Complete circuit not shown (see Figure 32). Pin numbers are for the TO-220 package. Figure 35. Undervoltage Lockout for Buck-Boost Circuit Complete circuit not shown. Pin numbers are for the TO-220 package. Figure 36. Delayed Startup Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback 23 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com Pin numbers are for the TO-220 package. Figure 37. 1.2V to 55V Adjustable 1A Power Supply with Low Output Ripple Definition of Terms BUCK REGULATOR A switching regulator topology in which a higher voltage is converted to a lower voltage. Also known as a step-down switching regulator. BUCK-BOOST REGULATOR A switching regulator topology in which a positive voltage is converted to a negative voltage without a transformer. DUTY CYCLE (D) Ratio of the output switch's on-time to the oscillator period. (17) CATCH DIODE OR CURRENT STEERING DIODE The diode which provides a return path for the load current when the LM2575 switch is OFF. EFFICIENCY () The proportion of input power actually delivered to the load. (18) CAPACITOR EQUIVALENT SERIES RESISTANCE (ESR) The purely resistive component of a real capacitor's impedance (see Figure 38). It causes power loss resulting in capacitor heating, which directly affects the capacitor's operating lifetime. When used as a switching regulator output filter, higher ESR values result in higher output ripple voltages. Figure 38. Simple Model of a Real Capacitor Most standard aluminum electrolytic capacitors in the 100 F-1000 F range have 0.5 to 0.1 ESR. Higher-grade capacitors ("low-ESR", "high-frequency", or "low-inductance"') in the 100 F-1000 F range generally have ESR of less than 0.15. EQUIVALENT SERIES INDUCTANCE (ESL) The pure inductance component of a capacitor (see Figure 38). The amount of inductance is determined to a large extent on the capacitor's construction. In a buck regulator, this unwanted inductance causes voltage spikes to appear on the output. OUTPUT RIPPLE VOLTAGE The AC component of the switching regulator's output voltage. It is usually dominated by the output capacitor's ESR multiplied by the inductor's ripple current (IIND). The peak-topeak value of this sawtooth ripple current can be determined by reading INDUCTOR RIPPLE CURRENT. 24 Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV LM1575, LM2575-N, LM2575HV www.ti.com SNVS106E - MAY 1999 - REVISED APRIL 2013 CAPACITOR RIPPLE CURRENT RMS value of the maximum allowable alternating current at which a capacitor can be operated continuously at a specified temperature. STANDBY QUIESCENT CURRENT (ISTBY) Supply current required by the LM2575 when in the standby mode (ON /OFF pin is driven to TTL-high voltage, thus turning the output switch OFF). INDUCTOR RIPPLE CURRENT (IIND) The peak-to-peak value of the inductor current waveform, typically a sawtooth waveform when the regulator is operating in the continuous mode (vs. discontinuous mode). CONTINUOUS/DISCONTINUOUS MODE OPERATION Relates to the inductor current. In the continuous mode, the inductor current is always flowing and never drops to zero, vs. the discontinuous mode, where the inductor current drops to zero for a period of time in the normal switching cycle. INDUCTOR SATURATION The condition which exists when an inductor cannot hold any more magnetic flux. When an inductor saturates, the inductor appears less inductive and the resistive component dominates. Inductor current is then limited only by the DC resistance of the wire and the available source current. OPERATING VOLT MICROSECOND CONSTANT (E*Top) The product (in VoIt*s) of the voltage applied to the inductor and the time the voltage is applied. This E*Top constant is a measure of the energy handling capability of an inductor and is dependent upon the type of core, the core area, the number of turns, and the duty cycle. Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV Submit Documentation Feedback 25 LM1575, LM2575-N, LM2575HV SNVS106E - MAY 1999 - REVISED APRIL 2013 www.ti.com REVISION HISTORY Changes from Revision D (April 2013) to Revision E * 26 Page Changed layout of National Data Sheet to TI format .......................................................................................................... 25 Submit Documentation Feedback Copyright (c) 1999-2013, Texas Instruments Incorporated Product Folder Links: LM1575 LM2575-N LM2575HV PACKAGE OPTION ADDENDUM www.ti.com 22-Sep-2017 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan Lead/Ball Finish MSL Peak Temp (2) (6) (3) Op Temp (C) Device Marking (4/5) LM2575HVMX-5.0/NOPB ACTIVE SOIC DW 24 1000 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 LM2575HVM -5.0 P+ LM2575HVN-5.0/NOPB ACTIVE PDIP NBG 16 20 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVN -5.0 P+ LM2575HVN-ADJ/NOPB ACTIVE PDIP NBG 16 20 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVN -ADJ P+ LM2575HVS-12 NRND DDPAK/ TO-263 KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575HVS -12 P+ LM2575HVS-12/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS -12 P+ LM2575HVS-15 NRND DDPAK/ TO-263 KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575HVS -15 P+ LM2575HVS-15/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS -15 P+ LM2575HVS-3.3/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS -3.3 P+ LM2575HVS-5.0 NRND DDPAK/ TO-263 KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575HVS -5.0 P+ LM2575HVS-5.0/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS -5.0 P+ LM2575HVS-ADJ NRND DDPAK/ TO-263 KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575HVS -ADJ P+ LM2575HVS-ADJ/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS -ADJ P+ LM2575HVSX-15/NOPB ACTIVE DDPAK/ TO-263 KTT 5 500 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS -15 P+ LM2575HVSX-3.3/NOPB ACTIVE DDPAK/ TO-263 KTT 5 500 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS -3.3 P+ LM2575HVSX-5.0 NRND DDPAK/ TO-263 KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575HVS -5.0 P+ LM2575HVSX-5.0/NOPB ACTIVE DDPAK/ TO-263 KTT 5 500 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS -5.0 P+ LM2575HVSX-ADJ NRND DDPAK/ TO-263 KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575HVS -ADJ P+ Addendum-Page 1 Samples PACKAGE OPTION ADDENDUM www.ti.com Orderable Device 22-Sep-2017 Status (1) Package Type Package Pins Package Drawing Qty Eco Plan Lead/Ball Finish MSL Peak Temp (2) (6) (3) Op Temp (C) Device Marking (4/5) LM2575HVSX-ADJ/NOPB ACTIVE DDPAK/ TO-263 KTT 5 500 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575HVS -ADJ P+ LM2575HVT-12 NRND TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575HVT -12 P+ LM2575HVT-12/LB03 NRND TO-220 NDH 5 45 TBD Call TI Call TI LM2575HVT -12 P+ LM2575HVT-12/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575HVT -12 P+ LM2575HVT-12/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVT -12 P+ LM2575HVT-15 NRND TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575HVT -15 P+ LM2575HVT-15/LB03 NRND TO-220 NDH 5 45 TBD Call TI Call TI LM2575HVT -15 P+ LM2575HVT-15/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575HVT -15 P+ LM2575HVT-15/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575HVT-3.3/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575HVT-3.3/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVT -3.3 P+ LM2575HVT-5.0 NRND TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575HVT -5.0 P+ LM2575HVT-5.0/LB03 NRND TO-220 NDH 5 45 TBD Call TI Call TI LM2575HVT -5.0 P+ LM2575HVT-5.0/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575HVT -5.0 P+ LM2575HVT-5.0/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVT -5.0 P+ LM2575HVT-ADJ NRND TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575HVT -ADJ P+ LM2575HVT-ADJ/LB03 NRND TO-220 NDH 5 45 TBD Call TI Call TI LM2575HVT -ADJ P+ LM2575HVT-ADJ/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575HVT -ADJ P+ Addendum-Page 2 -40 to 125 LM2575HVT -15 P+ LM2575HVT -3.3 P+ Samples PACKAGE OPTION ADDENDUM www.ti.com 22-Sep-2017 Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan Lead/Ball Finish MSL Peak Temp (2) (6) (3) Op Temp (C) Device Marking (4/5) LM2575HVT-ADJ/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2575HVT -ADJ P+ LM2575M-5.0 NRND SOIC DW 24 30 TBD Call TI Call TI -40 to 125 LM2575M -5.0 P+ LM2575M-5.0/NOPB ACTIVE SOIC DW 24 30 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 LM2575M -5.0 P+ LM2575M-ADJ/NOPB ACTIVE SOIC DW 24 30 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 LM2575M -ADJ P+ LM2575MX-5.0/NOPB ACTIVE SOIC DW 24 1000 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 LM2575M -5.0 P+ LM2575MX-ADJ/NOPB ACTIVE SOIC DW 24 1000 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 LM2575M -ADJ P+ LM2575N-5.0/NOPB ACTIVE PDIP NBG 16 20 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2575N -5.0 P+ LM2575N-ADJ/NOPB ACTIVE PDIP NBG 16 20 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2575N -ADJ P+ LM2575S-12/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575S -12 P+ LM2575S-15/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575S -15 P+ LM2575S-3.3 NRND DDPAK/ TO-263 KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575S -3.3 P+ LM2575S-3.3/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575S -3.3 P+ LM2575S-5.0 NRND DDPAK/ TO-263 KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575S -5.0 P+ LM2575S-5.0/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575S -5.0 P+ LM2575S-ADJ NRND DDPAK/ TO-263 KTT 5 45 TBD Call TI Call TI -40 to 125 LM2575S -ADJ P+ LM2575S-ADJ/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575S -ADJ P+ LM2575SX-12/NOPB ACTIVE DDPAK/ TO-263 KTT 5 500 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575S -12 P+ LM2575SX-15/NOPB ACTIVE DDPAK/ TO-263 KTT 5 500 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575S -15 P+ Addendum-Page 3 Samples PACKAGE OPTION ADDENDUM www.ti.com 22-Sep-2017 Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan Lead/Ball Finish MSL Peak Temp (2) (6) (3) Op Temp (C) Device Marking (4/5) LM2575SX-3.3/NOPB ACTIVE DDPAK/ TO-263 KTT 5 500 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575S -3.3 P+ LM2575SX-5.0 NRND DDPAK/ TO-263 KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575S -5.0 P+ LM2575SX-5.0/NOPB ACTIVE DDPAK/ TO-263 KTT 5 500 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575S -5.0 P+ LM2575SX-ADJ NRND DDPAK/ TO-263 KTT 5 500 TBD Call TI Call TI -40 to 125 LM2575S -ADJ P+ LM2575SX-ADJ/NOPB ACTIVE DDPAK/ TO-263 KTT 5 500 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2575S -ADJ P+ LM2575T-12 NRND TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575T -12 P+ LM2575T-12/LB03 NRND TO-220 NDH 5 45 TBD Call TI Call TI LM2575T -12 P+ LM2575T-12/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575T -12 P+ LM2575T-12/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2575T -12 P+ LM2575T-15 NRND TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575T -15 P+ LM2575T-15/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575T-15/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575T-3.3/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575T-3.3/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2575T -3.3 P+ LM2575T-5.0 NRND TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575T -5.0 P+ LM2575T-5.0/LB03 NRND TO-220 NDH 5 45 TBD Call TI Call TI LM2575T -5.0 P+ LM2575T-5.0/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575T -5.0 P+ LM2575T-5.0/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM Addendum-Page 4 LM2575T -15 P+ -40 to 125 LM2575T -15 P+ LM2575T -3.3 P+ -40 to 125 LM2575T -5.0 P+ Samples PACKAGE OPTION ADDENDUM www.ti.com Orderable Device 22-Sep-2017 Status (1) Package Type Package Pins Package Drawing Qty Eco Plan Lead/Ball Finish MSL Peak Temp (2) (6) (3) Op Temp (C) Device Marking (4/5) LM2575T-ADJ NRND TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2575T-ADJ/LB03 NRND TO-220 NDH 5 45 TBD Call TI Call TI LM2575T -ADJ P+ LM2575T-ADJ/LF02 ACTIVE TO-220 NEB 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575T -ADJ P+ LM2575T-ADJ/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2575T -ADJ P+ LM2575T-ADJ/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2575T -ADJ P+ LM2575T -ADJ P+ (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based flame retardants must also meet the <=1000ppm threshold requirement. (3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. (4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device. (5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Device Marking for that device. (6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish value exceeds the maximum column width. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and Addendum-Page 5 Samples PACKAGE OPTION ADDENDUM www.ti.com 22-Sep-2017 continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis. Addendum-Page 6 PACKAGE MATERIALS INFORMATION www.ti.com 5-Dec-2014 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant LM2575HVMX-5.0/NOPB SOIC DW 24 1000 330.0 24.4 10.8 15.9 3.2 12.0 24.0 Q1 LM2575HVSX-15/NOPB DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 LM2575HVSX-3.3/NOPB DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 LM2575HVSX-5.0/NOPB DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 LM2575HVSX-ADJ/NOPB DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 LM2575HVSX-5.0 LM2575HVSX-ADJ LM2575MX-5.0/NOPB SOIC DW 24 1000 330.0 24.4 10.8 15.9 3.2 12.0 24.0 Q1 LM2575MX-ADJ/NOPB SOIC DW 24 1000 330.0 24.4 10.8 15.9 3.2 12.0 24.0 Q1 LM2575SX-12/NOPB DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 LM2575SX-15/NOPB DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 LM2575SX-3.3/NOPB DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 Pack Materials-Page 1 PACKAGE MATERIALS INFORMATION www.ti.com 5-Dec-2014 Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant LM2575SX-5.0 DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 LM2575SX-5.0/NOPB DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 LM2575SX-ADJ DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 LM2575SX-ADJ/NOPB DDPAK/ TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM2575HVMX-5.0/NOPB SOIC DW 24 1000 367.0 367.0 45.0 LM2575HVSX-15/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2575HVSX-3.3/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2575HVSX-5.0 DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2575HVSX-5.0/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2575HVSX-ADJ DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2575HVSX-ADJ/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2575MX-5.0/NOPB SOIC DW 24 1000 367.0 367.0 45.0 LM2575MX-ADJ/NOPB SOIC DW 24 1000 367.0 367.0 45.0 LM2575SX-12/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 Pack Materials-Page 2 PACKAGE MATERIALS INFORMATION www.ti.com 5-Dec-2014 Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM2575SX-15/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2575SX-3.3/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2575SX-5.0 DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2575SX-5.0/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2575SX-ADJ DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2575SX-ADJ/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 Pack Materials-Page 3 MECHANICAL DATA NEB0005B www.ti.com PACKAGE OUTLINE KC0005A TO-220 - 16.51 mm max height SCALE 0.850 TO-220 4.83 4.06 10.67 9.65 3.05 2.54 B 1.40 1.14 A 6.86 5.69 3.71-3.96 8.89 6.86 (6.275) 12.88 10.08 OPTIONAL CHAMFER 16.51 MAX 2X (R1) OPTIONAL 9.25 7.67 C (4.25) PIN 1 ID (OPTIONAL) NOTE 3 14.73 12.29 1 5X 0.25 5 0.61 0.30 1.02 0.64 C A B 3.05 2.03 4X 1.7 6.8 1 5 4215009/A 01/2017 NOTES: 1. All controlling linear dimensions are in inches. Dimensions in brackets are in millimeters. Any dimension in brackets or parenthesis are for reference only. Dimensioning and tolerancing per ASME Y14.5M. 2. This drawing is subject to change without notice. 3. Shape may vary per different assembly sites. www.ti.com EXAMPLE BOARD LAYOUT KC0005A TO-220 - 16.51 mm max height TO-220 4X (1.45) PKG 0.07 MAX ALL AROUND 0.07 MAX ALL AROUND METAL TYP (1.45) PKG (2) 4X (2) 1 (R0.05) TYP 5X ( 1.2) SOLDER MASK OPENING, TYP (1.7) TYP 5 FULL R TYP (6.8) LAND PATTERN NON-SOLDER MASK DEFINED SCALE:12X 4215009/A 01/2017 www.ti.com MECHANICAL DATA NDH0005D www.ti.com MECHANICAL DATA NBG0016G www.ti.com MECHANICAL DATA KTT0005B TS5B (Rev D) BOTTOM SIDE OF PACKAGE www.ti.com MECHANICAL DATA NEB0005F www.ti.com IMPORTANT NOTICE Texas Instruments Incorporated (TI) reserves the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. 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Life-critical medical equipment is medical equipment where failure of such equipment would cause serious bodily injury or death (e.g., life support, pacemakers, defibrillators, heart pumps, neurostimulators, and implantables). Such equipment includes, without limitation, all medical devices identified by the U.S. Food and Drug Administration as Class III devices and equivalent classifications outside the U.S. TI may expressly designate certain products as completing a particular qualification (e.g., Q100, Military Grade, or Enhanced Product). Designers agree that it has the necessary expertise to select the product with the appropriate qualification designation for their applications and that proper product selection is at Designers' own risk. Designers are solely responsible for compliance with all legal and regulatory requirements in connection with such selection. Designer will fully indemnify TI and its representatives against any damages, costs, losses, and/or liabilities arising out of Designer's noncompliance with the terms and provisions of this Notice. Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265 Copyright (c) 2017, Texas Instruments Incorporated Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Texas Instruments: LM2575M-5.0 LM2575M-5.0/NOPB LM2575M-ADJ LM2575M-ADJ/NOPB LM2575MX-5.0/NOPB LM2575MXADJ/NOPB LM2575N-5.0/NOPB LM2575N-ADJ/NOPB LM2575S-12/NOPB LM2575S-15/NOPB LM2575S-3.3 LM2575S-3.3/NOPB LM2575S-5.0 LM2575S-5.0/NOPB LM2575S-ADJ LM2575S-ADJ/NOPB LM2575SX-12 LM2575SX-12/NOPB LM2575SX-15/NOPB LM2575SX-3.3/NOPB LM2575SX-5.0 LM2575SX-5.0/NOPB LM2575SXADJ LM2575SX-ADJ/NOPB LM2575T-12 LM2575T-12/LB03 LM2575T-12/LF03 LM2575T-12/NOPB LM2575T-15 LM2575T-15/LF03 LM2575T-15/NOPB LM2575T-3.3/LF03 LM2575T-3.3/NOPB LM2575T-5.0 LM2575T-5.0/LB03 LM2575T-5.0/LF02 LM2575T-5.0/LF03 LM2575T-5.0/LF04 LM2575T-5.0/NOPB LM2575T-ADJ LM2575T-ADJ/LB03 LM2575T-ADJ/LF02 LM2575T-ADJ/LF03 LM2575T-ADJ/NOPB