MIC49150 1.5A Low Voltage LDO Regulator w/Dual Input Voltages General Description Features The MIC49150 is a high-bandwidth, low-dropout, 1.5A voltage regulator ideal for powering core voltages of lowpower microprocessors. The MIC49150 implements a dual supply configuration allowing for very low output impedance and very fast transient response. The MIC49150 requires a bias input supply and a main input supply, allowing for ultra-low input voltages on the main supply rail. The input supply operates from 1.4V to 6.5V and the bias supply requires between 3V and 6.5V for proper operation. The MIC49150 offers fixed output voltages from 0.9V to 1.8V and adjustable output voltages down to 0.9V. The MIC49150 requires a minimum of output capacitance for stability, working optimally with small ceramic capacitors. The MIC49150 is available in an 8-pin power MSOP package and a 5-pin S-Pak. Its operating temperature range is -40C to +125C. Data sheets and support documentation can be found on Micrel's web site at www.micrel.com. * Input Voltage Range: - VIN: 1.4V to 6.5V - VBIAS: 3.0V to 6.5V * Stable with 1F ceramic capacitor * 1% initial tolerance * Maximum dropout voltage (VIN-VOUT) of 500mV over temperature * Adjustable output voltage down to 0.9V * Ultra fast transient response (Up to 10MHz bandwidth) * Excellent line and load regulation specifications * Logic controlled shutdown option * Thermal shutdown and current limit protection * Power MSOP-8 and S-Pak packages * Junction temperature range: -40C to 125C Applications * * * * * * Graphics processors PC add-in cards Microprocessor core voltage supply Low voltage digital ICs High efficiency linear power supplies SMPS post regulators Typical Application VIN = 1.8V MIC49150BR IN OUT VOUT = 1.0V R1 VBIAS = 3.3V CBIAS = 1F Ceramic BIAS ADJ GND R2 COUT = 1F Ceramic CIN = 1F Ceramic Low Voltage, Fast Transient Response Regulator Micrel Inc. * 2180 Fortune Drive * San Jose, CA 95131 * USA * tel +1 (408) 944-0800 * fax + 1 (408) 474-1000 * http://www.micrel.com November 2006 1 M9999-111306 Micrel, Inc. MIC49150 Ordering Information Part Number Output Current Voltage Junction Temp. Range Package MIC49150-0.9YMM 1.5A 0.9V -40 to +125C 8-Pin Power MSOP MIC49150-1.2BMM MIC49150-1.2YMM 1.5A 1.2V -40 to +125C 8-Pin Power MSOP MIC49150-1.5BMM MIC49150-1.5YMM 1.5A 1.5V -40 to +125C 8-Pin Power MSOP MIC49150-1.8BMM MIC49150-1.8YMM 1.5A 1.8V -40 to +125C 8-Pin Power MSOP MIC49150BMM MIC49150YMM 1.5A Adj. -40 to +125C 8-Pin Power MSOP MIC49150-0.9BR MIC49150-0.9WR* 1.5A 0.9V -40 to +125C 5-Pin S-PAK MIC49150-1.2BR MIC49150-1.2WR* 1.5A 1.2V -40 to +125C 5-Pin S-PAK MIC49150-1.5BR MIC49150-1.5WR* 1.5A 1.5V -40 to +125C 5-Pin S-PAK MIC49150-1.8BR MIC49150-1.8WR* 1.5A 1.8V -40 to +125C 5-Pin S-PAK MIC49150BR MIC49150WR* 1.5A Adj. -40 to +125C 5-Pin S-PAK Standard Pb-Free / RoHS Compliant MIC49150-0.9BMM * RoHS Compliant with `high-melting solder' exemption. EN/ADJ. 1 8 GND VBIAS 2 7 GND VIN 3 6 GND VOUT 4 5 GND TAB Pin Configuration 8-Pin Power MSPO (MM) 5 4 3 2 1 VOUT VIN GND VBIAS EN/ADJ. 5-Pin S-Pak (R) Pin Description Pin Number 8-MSOP Pin Number 1 1 Pin Name Pin Name 5-SPak EN Enable (Input): CMOS compatible input. Logic high = enable, logic low = shutdown. ADJ Adjustable regulator feedback input. Connect to resistor voltage divider. Input Bias Voltage for powering all circuitry on the regulator with the exception of the output power device. 2 2 VBIAS 3 4 VIN Input voltage which supplies current to the output power device. 4 5 OUT Regulator Output. 5/6/7/8 3 GND Ground (TAB is connected to ground on S-Pak). November 2006 2 M9999-111306 Micrel, Inc. MIC49150 Absolute Maximum Ratings(1) Operating Ratings(2) Supply Voltage (VIN) .........................................................8V Bias Supply Voltage (VBIAS)..............................................8V Enable Input Voltage (VEN)...............................................8V Power Dissipation .....................................Internally Limited ESD Rating(3) .................................................................. 4kV Supply Voltage (VIN)......................................... 1.4V to 6.5V Bias Supply Voltage (VBIAS)................................. 3V to 6.5V Enable Input Voltage (VEN).................................. 0V to 6.5V Junction Temperature (TJ) ..................-40C TJ +125C Package Thermal Resistance MSOP-8 (JA).....................................................80C/W S-Pak (JC) ..........................................................2C/W Electrical Characteristics(4) TA = 25C with VBIAS = VOUT + 2.1V; VIN = VOUT + 1V; bold values indicate -40C< TJ < +125C, unless noted(5). Parameter Condition Min Output Voltage Accuracy At 25C Over temperature range -1 -2 Line Regulation VIN = VOUT +1V to 6.5V -0.1 Load Regulation Dropout Voltage (VIN - VOUT) Typ Max Units +1 +2 % % 0.01 +0.1 %/V IL = 0mA to 1.5A 0.2 1 1.5 % % IL = 750mA 130 IL = 1.5A 280 200 300 400 500 mV mV mV mV Dropout Voltage (VBIAS - VOUT), Note 5 IL = 750mA IL = 1.5A 1.3 1.65 1.9 2.1 V V V Ground Pin Current, Note 6 IL = 0mA IL = 1.5A 15 15 25 30 mA mA mA Ground Pin Current in Shutdown VEN 0.6V, (IBIAS + ICC), Note 7 0.5 1 2 A A Current thru VBIAS IL = 0mA 9 15 25 mA mA mA Current Limit MIC49150 1.6 3.4 4 A A Enable Input Threshold (Fixed Voltage only) Regulator enable Regulator shutdown 1.6 0.6 V V Enable Pin Input Current Independent of state 0.1 1 A 0.9 0.909 0.918 V V 32 IL = 1.5A 2.3 Enable Input (Note 7) Reference 0.891 0.882 Reference Voltage Notes: 1. Exceeding the absolute maximum rating may damage the device. 2. The device is not guaranteed to function outside its operating rating. 3. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF. 4. Specification for packaged product only. 5. For VOUT 1V, VBIAS dropout specification does not apply due to a minimum 3V VBIAS input. 6. IGND = IBIAS + (IIN - IOUT). At high loads, input current on VIN will be less than the output current, due to drive current being supplied by VBIAS. 7. Fixed output voltage versions only. November 2006 3 M9999-111306 Micrel, Inc. MIC49150 Typical Characteristics 0.6 0.4 100 50 1.6 OUTPUT VOLTAGE (V) 0.8 0.6 0.4 VBIAS = 5V 0.2 V OUT = 1.5V 0.5 1 1.5 2 INPUT VOLTAGE (V) 2.5 BIAS CURRENT (mA) 250 VADJ = 0V IOUT = 1.5A VIN = 2.5V 200 150 100 *Note: Maximum bias current is bias current with input in dropout 3.5 4 4.5 5 5.5 6 BIAS VOLTAGE (V) November 2006 6.5 1600 1400 1200 1000 800 1.2 1.0 0.8 0.6 0.4 VIN = 2.5V IOUT = 1.5A VOUT = 1.5V 0.2 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE(C) Load Regulation 1.504 1.2 IOUT = 10mA 1.0 0.8 IOUT = 1.5A 0.6 0.4 VIN = 2.5V VOUT = 1.5V 0.2 300 1.8 1.6 1.4 1.505 1.4 0 0 Maximum Bias Current vs. Bias Voltage 3 VBIAS = 5V IOUT = 1.5A VOUT = 1. 5V Dropout Characteristics (Bias Voltage) IOUT = 1.5A 50 150 Dropout Characteristics (Input Voltage) 1.0 300 200 OUTPUT CURRENT (mA) 1.2 0 0 250 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE(C) IOUT = 10mA 1.4 2.0 300 1600 1400 1200 800 0 1.6 600 0.2 1000 VIN = 2.5V VOUT = 1.5V Dropout Voltage vs. Temperature (Bias Supply) 1 2 3 4 5 6 BIAS VOLTAGE (V) 1.503 1.502 1.501 1.500 1.499 1.498 1.497 VBIAS = 5V VIN = 2.5V 1.496 1.495 7 OUTPUT CURRENT (mA) Maximum Bias Current vs. Temperature 45 Bias Current vs. Temperature VIN = 2.5V VOUT = 1.5V VBIAS = 5V 40 250 200 VBIAS = 5V VADJ = 0V VIN = 2.5V 150 100 50 1600 0.8 Dropout Voltage vs. Temperature (Input Supply) 1400 1.0 OUTPUT CURRENT (mA) 1200 1.2 0 1000 1000 350 DROPOUT VOLTAGE (mV) 400 1.4 200 DROPOUT VOLTAGE (V) 1.6 0 0.1 1 10 100 FREQUENCY (kHz) Dropout Voltage (Bias Supply) 0 OUTPUT VOLTAGE (V) 0 0.01 1000 VBIAS = 5V VOUT = 1.0V 50 800 0.1 1 10 100 FREQUENCY (kHz) 1.8 BIAS CURRENT (mA) 10 100 600 0 0.01 20 600 10 30 150 400 20 VBIAS = 3.3V VIN = 1.8V VOUT = 1.0V IOUT = 1.5A COUT = 1F ceramic 0 30 40 200 VBIAS = 3.3V VIN = 1.8V VOUT = 1.0V IOUT = 1.5A COUT = 1F ceramic OUTPUT VOLTAGE (V) 40 200 0 50 250 200 50 DROPOUT VOLTAGE (mV) 60 DROPOUT VOLTAGE (V) 70 60 300 BIAS CURRENT (mA) 70 PSRR (dB) 80 Dropout Voltage (Input Suppl ) 400 Power Supply Rejection Ratio (Bias Suppl ) 80 400 PSRR (dB) Power Supply Rejection Ratio (Input Suppl ) 35 30 I = 750mA OUT 25 20 15 I OUT = 1500mA IOUT = 100mA 10 5 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE( C) 4 I = 10mA OUT 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) M9999-111306 Micrel, Inc. MIC49150 Typical Characteristics (cont.) 8 6 IOUT = 0mA VIN = 2.5V VOUT = 1.5V 4 2 0 1600 1400 1200 1000 800 600 400 0 0 200 10 3 3.5 OUTPUT CURRENT (mA) Bias Current vs. Bias Voltage 30 IBIAS 20 10 3 BIAS CURRENT (mA) 300 3.5 4 4.5 5 5.5 6 BIAS VOLTAGE (V) Bias Current vs. Input Voltage VBIAS = 5V 250 VOUT = 1.5V 1500mA 750mA 100 50 0 0 1.55 0.5 1 1.5 2 INPUT VOLTAGE (V) IOUT = 1500mA VIN = 2.5V VOUT = 1.5V 3.5 VBIAS = 5V 1.54 VIN = 2.5V 1.53 1.52 1.51 1.50 1.49 1.48 1.47 1.46 1.45 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) 4 4.5 5 5.5 6 BIAS VOLTAGE (V) 6.5 Reference Voltage vs. Input Voltage 0.900 3.0 2.4 3.4 4.4 5.4 INPUT VOLTAGE (V) 6.4 2.5 2.0 1.5 VBIAS = 5V VIN = 2.5V VOUT = 0V 0.5 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) 5 10 8 6 IOUT = 100mA VIN = 2.5V VOUT = 1.5V 4 2 3 3.5 4 4.5 5 5.5 6 BIAS VOLTAGE (V) 6.5 20 18 VBIAS = 5V 16 VOUT = 1.5V IOUT = 100mA 14 12 10 8 IOUT = 0mA 6 4 2 0 0 0.5 1 1.5 2 2.5 INPUT VOLTAGE (V) Reference Voltage vs. Bias Voltage VIN = 2.5V 0.900 0.899 3 Short Circuit Current vs. Temperature 1.0 IBIAS 0.901 VBIAS = 5V 0.899 1.4 2.5 Output Voltage vs. Temperature November 2006 20 3 Bias Current vs. Bias Voltage Bias Current vs. Input Voltage 30 10 12 0 6.5 IBIAS 0.901 200 150 40 0 6.5 REFERENCE VOLTAGE (V) 0 OUTPUT VOLTAGE (V) GROUND CURRENT (mA) 40 4 4.5 5 5.5 6 BIAS VOLTAGE (V) Bias Current vs. Bias Voltage 50 IOUT = 750mA VIN = 2.5V VOUT = 1.5V SHORT CIRCUIT CURRENT (A) GROUND CURRENT (mA) 50 GROUND CURRENT (mA) 20 10 BIAS CURRENT (mA) IBIAS REFERENCE VOLTAGE (V) 30 14 12 1.6 ENABLE THRESHOLD (V) CURRENT (mA) 40 Ground Current vs. Bias Voltage 14 VBIAS = 5V VIN = 2.5V VOUT = 1.5V GROUND CURRENT (mA) 50 Bias Current vs. Output Current 3.5 4 4.5 5 5.5 6 BIAS VOLTAGE (V) 6.5 Enable Threshold vs. Bias Voltage 1.4 ON 1.2 1.0 OFF 0.8 0.6 0.4 VIN = 2.5V 0.2 0 3 3.5 4 4.5 5 5.5 6 BIAS VOLTAGE (V) 6.5 M9999-111306 Micrel, Inc. MIC49150 Typical Characteristics (cont.) ENABLE THRESHOLD (V) 1.6 1.4 Enable Threshold vs. Temperature ON 1.2 1.0 0.8 OFF 0.6 0.4 0.2 VBIAS = 5V VIN = 2.5V 0 -40 -20 0 20 40 60 80 100 120 TEMPERATURE (C) November 2006 6 M9999-111306 Micrel, Inc. MIC49150 Functional Characteristics November 2006 7 M9999-111306 Micrel, Inc. MIC49150 Functional Diagram VBIAS VIN Ilimit VEN/ADJ Fixed Enable Bandgap Adj. VIN Open Circuit Fixed November 2006 8 R1 VOUT R2 M9999-111306 Micrel, Inc. MIC49150 type of ceramic capacitors. Z5U and Y5V dielectric capacitors change value by as much as 50% and 60% respectively over their operating temperature ranges. To use a ceramic chip capacitor with Y5V dielectric, the value must be much higher than an X7R ceramic or a tantalum capacitor to ensure the same capacitance value over the operating temperature range. Tantalum capacitors have a very stable dielectric (10% over their operating temperature range) and can also be used with this device. Application Information The MIC49150 is an ultra-high performance, low-dropout linear regulator designed for high current applications requiring fast transient response. The MIC49150 utilizes two input supplies, significantly reducing dropout voltage, perfect for low-voltage, DC-to-DC conversion. The MIC49150 requires a minimum of external components and obtains a bandwidth of up to 10MHz. As a Cap regulator, the output is tolerant of virtually any type of capacitor including ceramic type and tantalum type capacitors. The MIC49150 regulator is fully protected from damage due to fault conditions, offering linear current limiting and thermal shutdown. Input Capacitor An input capacitor of 1F or greater is recommended when the device is more than 4" away from the bulk supply capacitance, or when the supply is a battery. Small, surface-mount, ceramic chip capacitors can be used for the bypassing. The capacitor should be placed within 1" of the device for optimal performance. Larger values will help to improve ripple rejection by bypassing the input to the regulator, further improving the integrity of the output voltage. Bias Supply Voltage VBIAS, requiring relatively light current, provides power to the control portion of the MIC49150. VBIAS requires approximately 33mA for a 1.5A load current. Dropout conditions require higher currents. Most of the biasing current is used to supply the base current to the pass transistor. This allows the pass element to be driven into saturation, reducing the dropout to 300mV at a 1.5A load current. Bypassing on the bias pin is recommended to improve performance of the regulator during line and load transients. Small ceramic capacitors from VBIAS to ground help reduce high frequency noise from being injected into the control circuitry from the bias rail and are good design practice. Good bypass techniques typically include one larger capacitor such as 1F ceramic and smaller valued capacitors such as 0.01F or 0.001F in parallel with that larger capacitor to decouple the bias supply. The VBIAS input voltage must be 1.6V above the output voltage with a minimum VBIAS input voltage of 3 volts. Thermal Design Linear regulators are simple to use. The most complicated design parameters to consider are thermal characteristics. Thermal design requires the following application-specific parameters: * Maximum ambient temperature (TA) * Output current (IOUT) * Output voltage (VOUT) * Input voltage (VIN) * Ground current (IGND) First, calculate the power dissipation of the regulator from these numbers and the device parameters from this datasheet. PD = VIN x IIN + VBIAS x IBIAS - VOUT x IOUT The input current will be less than the output current at high output currents as the load increases. The bias current is a sum of base drive and ground current. Ground current is constant over load current. Then the heat sink thermal resistance is determined with this formula: Input Supply Voltage VIN provides the high current to the collector of the pass transistor. The minimum input voltage is 1.4V, allowing con-version from low voltage supplies. Output Capacitor The MIC49150 requires a minimum of output capacitance to maintain stability. However, proper capacitor selection is important to ensure desired transient response. The MIC49150 is specifically designed to be stable with virtually any capacitance value and ESR. A 1F ceramic chip capacitor should satisfy most applications. Output capacitance can be increased without bound. See "Typical Characteristic" for examples of load transient response. X7R dielectric ceramic capacitors are recommended because of their temperature performance. X7R-type capacitors change capacitance by 15% over their operating temperature range and are the most stable November 2006 TJ(MAX) - TA SA = PD - ( JC + CS ) The heat sink may be significantly reduced in applications where the maximum input voltage is known and large compared with the dropout voltage. Use a series input resistor to drop excessive voltage and distribute the heat between this resistor and the regulator. The low-dropout properties of the MIC49150 allow significant reductions in regulator power dissipation and the associated heat sink without compromising performance. When this technique is employed, a 9 M9999-111306 Micrel, Inc. MIC49150 capacitor of at least 1F is needed directly between the input and regulator ground. Refer to "Application Note 9" for further details and examples on thermal design and heat sink specification. MSOP-8 Minimum Load Current The MIC49150, unlike most other high current regulators, does not require a minimum load to maintain output voltage regulation. Power MSOP-8 Thermal Characteristics One of the secrets of the MIC49150's performance is its power MSOP-8 package featuring half the thermal resistance of a standard MSOP-8 package. Lower thermal resistance means more output current or higher input voltage for a given package size. Lower thermal resistance is achieved by joining the four ground leads with the die attach paddle to create a single-piece electrical and thermal conductor. This concept has been used by MOSFET manufacturers for years, proving very reliable and cost effective for the user. Thermal resistance consists of two main elements, JC (junction-to-case thermal resistance) and CA (case-toambient thermal resistance). See Figure 1. JC is the resistance from the die to the leads of the package. CA is the resistance from the leads to the ambient air and it includes CS (case-to-sink thermal resistance) and SA (sink-to-ambient thermal resistance). Using the power MSOP-8 reduces the JC dramatically and allows the user to reduce CA. The total thermal resistance, JA (junction-to-ambient thermal resistance) is the limiting factor in calculating the maximum power dissipation capability of the device. Typically, the power MSOP-8 has a JA of 80C/W, this is significantly lower than the standard MSOP-8 which is typically 160C/W. CA is reduced because pins 5 through 8 can now be soldered directly to a ground plane which significantly reduces the case-to-sink thermal resistance and sink to ambient thermal resistance. Low-dropout linear regulators from Micrel are rated to a maximum junction temperature of 125C. It is important not to exceed this maximum junction temperature during operation of the device. To prevent this maximum junction temperature from being exceeded, the appropriate ground plane heat sink must be used. q JA qJC ground plane heat sink area qCA AMBIENT printed circuit board Figure 1. Thermal Resistance Figure 2 shows copper area versus power dissipation with each trace corresponding to a different temperature rise above ambient. From these curves, the minimum area of copper necessary for the part to operate safely can be determined. The maximum allowable temperature rise must be calculated to determine operation along which curve. 900 COPPER AREA (mm2) 800 700 600 500 400 300 200 100 0 0 0.25 0.50 0.75 1.00 1.25 1.50 POWER DISSIPATION (W) Figure 2. Copper Area vs. Power-MSOP Power Dissipation (TJA) COPPER AREA (mm2) 900 800 700 TJ = 125C 85C 50C 25C 600 500 400 300 200 100 0 0 0.25 0.50 0.75 1.00 1.25 1.50 POWER DISSIPATION (W) Figure 3. Copper Area vs. Power-MSOP Power Dissipation (TA) November 2006 10 M9999-111306 Micrel, Inc. MIC49150 T = TJ(max) - TA(max) T J(max) = 125C TA(max) = maximum ambient operating temperature For example, the maximum ambient temperature is 50C, the T is determined as follows: T = 125C - 50C T = 75C Using Figure 2, the minimum amount of required copper can be determined based on the required power dissipation. Power dissipation in a linear regulator is calculated as follows: PD = VIN x IIN + VBIAS x IBIAS - VOUT x IOUT Using a typical application of 750mA output current, 1.2V output voltage, 1.8V input voltage and 3.3V bias voltage, the power dissipation is as follows: PD = (1.8V) x (730mA) + 3.3V(30mA) - 1.2V(750mA) At full current, a small percentage of the output current is supplied from the bias supply, therefore the input current is less than the output current. PD = 513mW From Figure 2, the minimum current of copper required to operate this application at a T of 75C is less than 100mm2. The JA of this package is ideally 80C/W, but it will vary depending upon the availability of copper ground plane to which it is attached. Adjustable Regulator Design The MIC49150 adjustable version allows programming the output voltage anywhere between 0.9Vand 5V. Two resistors are used. The resistor value between VOUT and the adjust pin should not exceed 10k. Larger values can cause instability. The resistor values are calculated by: V R1 = R2 x OUT - 1 0.9 Where VOUT is the desired output voltage. Enable The fixed output voltage versions of the MIC49150 feature an active high enable input (EN) that allows onoff control of the regulator. Current drain reduces to "zero" when the device is shutdown, with only microamperes of leakage current. The EN input has TTL/CMOS compatible thresholds for simple logic interfacing. EN may be directly tied to VIN and pulled up to the maximum supply voltage. Quick Method Determine the power dissipation requirements for the design along with the maximum ambient temperature at which the device will be operated. Refer to Figure 3, which shows safe operating curves for three different ambient temperatures: 25C, 50C and 85C. From these curves, the minimum amount of copper can be determined by knowing the maxi-mum power dissipation required. If the maximum ambient temperature is 50C and the power dissipation is as above, 513mW, the curve in Figure 3 shows that the required area of copper is less than 100mm2. November 2006 11 M9999-111306 Micrel, Inc. MIC49150 Package Information 8-Pin MSOP (MM) 5-Pin S-Pak (R) November 2006 12 M9999-111306 Micrel, Inc. MIC49150 MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser's use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser's own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. (c) 2003 Micrel, Incorporated. November 2006 13 M9999-111306