DS1080L Spread-Spectrum Crystal Multiplier General Description The DS1080L is a low-jitter, crystal-based clock generator with an integrated phase-locked loop (PLL) to generate spread-spectrum clock outputs from 16MHz to 134MHz. The device is pin-programmable to select the clock multiplier rate as well as the dither magnitude. The DS1080L has a spread-spectrum disable mode and a power-down mode to conserve power. Applications Automotive Features Generates Spread-Spectrum Clocks from 16MHz to 134MHz Selectable Clock Multiplier Rates of 1x, 2x, and 4x Center Spread-Spectrum Dithering Selectable Spread-Spectrum Modulation Magnitudes of 0.5%, 1.0%, and 1.5% Spread-Spectrum Disable Mode Low Cycle-to-Cycle Jitter Power-Down Mode with High-Impedance Output Cable Modems Cell Phones Low Power Consumption Computer Peripherals 3.0V to 3.6V Single-Supply Operation Copiers -40C to +125C Temperature Operation Infotainment Small 8-Lead SOP Package PCs Printers Ordering Information Pin Configuration PART TOP VIEW + X1 8 1 GND 2 CMSEL X2 7 VCC 3 6 SSO SMSEL 4 5 PDN DS1080L TEMP RANGE PIN-PACKAGE DS1080LU+ -40C to +125C 8 SOP DS1080LU/V+ -40C to +125C 8 SOP DS1080LU/V+T -40C to +125C 8 SOP DS1080LU+T -40C to +125C 8 SOP +Denotes a lead(Pb)-free/RoHS-compliant package. /V denotes an automotive qualified part. T = Tape and reel. SOP For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated's website at www.maximintegrated.com. 19-4997; Rev 5; 3/13 DS1080L Spread-Spectrum Crystal Multiplier ABSOLUTE MAXIMUM RATINGS Voltage on VCC Relative to GND ...........................-0.3V to +4.3V Voltage on Any Lead Relative to GND .................-0.3V to (VCC + 0.3V), not to exceed +4.3V Continuous Power Dissipation (TA = +70C) SOP (derate 4.5mW/C above +70C).......................362mW Operating Temperature Range .........................-40C to +125C Storage Temperature Range .............................-55C to +125C Lead Temperature (soldering, 10s) .................................+300C Soldering Temperature (reflow) .......................................+260C Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. RECOMMENDED OPERATING CONDITIONS (TA = -40C to +125C, unless otherwise noted.) PARAMETER SYMBOL MAX UNITS 3.0 3.6 V VIH 0.8 x VCC VCC + 0.3 V VIL VGND 0.3 0.2 x VCC V Supply Voltage VCC Input Logic 1 Input Logic 0 CONDITIONS (Note 1) MIN TYP Input Logic Open I IF 0V < VIN < VCC (Note 2) 1 A Input Leakage I IL 0V < VIN < VCC (Note 3) f SSO < 67MHz 80 A SSO Load Crystal or Clock Input Frequency CSSO XESR Clock Input Duty Cycle FINDC Crystal Parallel Load Capacitance 10 101MHz f SSO < 134MHz 7 f IN Crystal ESR CL 15 67MHz f SSO < 101MHz 16.0 pF 33.4 40 (Note 4) MHz 90 60 % 18 pF MAX UNITS 15 mA DC ELECTRICAL CHARACTERISTICS (VCC = +3.0V to +3.6V, TA = -40C to +125C, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS Supply Current ICC1 CSSO = 15pF, SSO = 16MHz Power-Down Current ICCQ PDN = GND, all input pins open Output Leakage (SSO) IOZ PDN = GND Low-Level Output Voltage (SSO) VOL IOL = 4mA High-Level Output Voltage (SSO) VOH IOH = -4mA Input Capacitance (X1/X2) CIN (Note 5) 2 MIN TYP -1 2.4 200 A +1 A 0.4 V V 5 pF Maxim Integrated DS1080L Spread-Spectrum Crystal Multiplier AC ELECTRICAL CHARACTERISTICS (VCC = +3.0 to +3.6V, TA = -40C to +125C, unless otherwise noted.) PARAMETER SSO Duty Cycle SYMBOL SSODC CONDITIONS MIN TYP MAX Measured at VCC/2, CMSEL = 0 or open 40 60 Measured at VCC/2, CMSEL = 1 30 70 UNITS % Rise Time tR (Note 6) 1.6 ns Fall Time tF (Note 6) 1.6 ns Peak Cycle-to-Cycle Jitter tJ fSSO = 16MHz, TA = -40 to +85C, 10,000 cycles (Note 5) 75 ps Power-Up Time Power-Down Time Dither Rate tPOR PDN pin (Note 7) tPDN PDN pin (Notes 8 and 9) fDITHER (Note 9) 16MHz 20 33.4MHz 11 100 ms ns fIN/992 Note 1: All voltages referenced to ground. Note 2: Maximum source/sink current applied to input to be considered an open. Typical voltage range between 0.4 x VCC and 0.55 x VCC. Note 3: Applicable to pins CMSEL, SMSEL, and PDN. Note 4: See information about CL1 and CL2 in the Applications Information section at the end of the data sheet. Note 5: Not production tested. Note 6: For 7pF load. Note 7: Time between PDN deasserted to output active. Note 8: Time between PDN asserted to output high impedance. Note 9: Guaranteed by design. Maxim Integrated 3 DS1080L Spread-Spectrum Crystal Multiplier Typical Operating Characteristics (VCC = 3.3V, TA = +25C, unless otherwise noted.) 11 10 9 AT 16MHz CMSEL = 1x 11 10 8 9 10 -40 SUPPLY VOLTAGE (V) 60 26 31 FREQUENCY (MHz) TEMPERATURE (C) DUTY CYCLE vs. TEMPERATURE 60 DS1080L toc04 AT 16MHz CMSEL = 1x 0.04 0.03 0.02 AT 16MHz 58 56 DUTY CYCLE (%) PDN SUPPLY CURRENT (mA) 0.05 21 16 110 PDN SUPPLY CURRENT vs. TEMPERATURE 0.06 13 9 7 3.4 15 DS1080L toc05 3.2 3.0 17 11 8 7 AT 16MHz CMSEL = 1x 19 SUPPLY CURRENT (mA) 12 SUPPLY CURRENT (mA) SUPPLY CURRENT (mA) 12 DS1080L toc02 AT 16MHz CMSEL = 1x SUPPLY CURRENT vs. FREQUENCY SUPPLY CURRENT vs. TEMPERATURE 13 DS1080L toc01 13 DS1080L toc03 SUPPLY CURRENT vs. SUPPLY VOLTAGE 54 52 50 48 46 44 0.01 42 0 10 60 40 110 -40 TEMPERATURE (C) 54 ATTENUATION (dB) DUTY CYCLE (%) 56 52 50 48 46 44 42 40 3.0 3.2 3.4 SUPPLY VOLTAGE (V) 4 110 FREQUENCY SPECTRUM AT 133.3MHz DS1080L toc06 AT 16MHz 58 60 TEMPERATURE (C) DUTY CYCLE vs. SUPPLY VOLTAGE 60 10 3.6 5 0 -5 -10 -15 -20 -25 -30 -35 -40 -45 -50 -55 -60 -65 129.3 1% DITHER NO DITHER 0.5% DITHER DS1080L toc07 -40 2% DITHER AT 133.3MHz 131.3 133.3 135.3 137.3 OUTPUT FREQUENCY (MHz) Maxim Integrated DS1080L Spread-Spectrum Crystal Multiplier Pin Description PIN NAME 1 X1 2 GND 3 4 FUNCTION Crystal Drive/Clock Input. A crystal with the proper loading capacitors is connected across X1 and X2. Instead of a crystal, a clock can be applied at the X1 input. Signal Ground CMSEL Clock Multiplier Select. Tri-level digital input. 0 = 1x Open = 2x 1 = 4x SMSEL Spread-Spectrum Magnitude Select. Tri-level digital input. 0 = 0.5% Open = 1.0% 1 = 1.5% 5 PDN Power-Down/Spread-Spectrum Disable. Tri-level digital input. 0 = Power-Down/SSO Three-Stated Open = Power-Up/Spread Spectrum Disabled 1 = Power-Up/Spread Spectrum Enabled 6 SSO Spread-Spectrum Clock Multiplier Output. Outputs a 1x, 2x, or 4x spread-spectrum version of the crystal or clock applied at the X1/X2 pins. 7 VCC Supply Voltage 8 X2 Crystal Drive Output. A crystal with the proper loading capacitors is connected across X1 and X2. If a clock is connected to X1, then X2 should be left open circuit. Block Diagram VCC X1 16MHz TO 33.4MHz X2 CL1 VCC fIN CRYSTAL OSCILLATOR 1x/2x/4x CLOCK MULTIPLYING PLL WITH SPREAD SPECTRUM SSO fSSO fSSO = 16MHz TO 134MHz CL2 PDN CMSEL SMSEL GND CONFIGURATION DECODE AND CONTROL DS1080L NOTE: SEE INFORMATION ABOUT CL1 AND CL2 IN THE APPLICATIONS INFORMATION SECTION AT THE END OF THE DATA SHEET. Maxim Integrated 5 DS1080L Spread-Spectrum Crystal Multiplier Detailed Description The DS1080L is a crystal multiplier with center spreadspectrum capability. A 16MHz to 33.4MHz crystal is connected to the X1 and X2 pins. Alternately, a 16MHz to 33.4MHz clock can be applied to X1 in place of the crystal. In such applications, X2 would be left open circuit. Using the CMSEL input, the user selects whether the attached crystal or input clock is multiplied by 1, 2, or 4. The DS1080L is capable of generating spreadspectrum clocks from 16MHz to 134MHz. The PLL can dither the output clock about its center frequency at a user-selectable magnitude. Using the SMSEL input, the user selects the dither magnitude. The PDN input can be used to place the device into a low-power standby mode where the SSO output is tristated. If the PDN pin is open, the SSO output is active but the spread-spectrum dithering is disabled. The spread-spectrum dither rate is fixed at f IN / 992 to keep the dither rate above the audio frequency range. On power-up, the output clock (SSO) remains three-stated until the PLL reaches a stable frequency (fSSO) and dither (fDITHER). Applications Information Crystal Selection The DS1080L requires a parallel resonating crystal operating in the fundamental mode, with an ESR of less than 90!. The crystal should be placed very close to the device to minimize excessive loading due to parasitic capacitances. Oscillator Input When driving the DS1080L using an external oscillator clock, consider the input (X1) to be high impedance. Crystal Capacitor Selection The load capacitors CL1 and CL2 are selected based on the crystal specifications (from the data sheet of the crystal used). The crystal parallel load capacitance is calculated as follows: CL = CL1 x CL2 + CIN CL1 + CL 2 Equation1 For the DS1080L use CL1 = CL2 = CLX. In this case, the equation then reduces to: CL = CLX + CIN 2 Equation 2 where CL1 = CL2 = CLX. Equation 2 is used to calculate the values of CL1 and CL2 based on values on CL and CIN noted in the data sheet electrical specifications. Power-Supply Decoupling To achieve best results, it is highly recommended that a decoupling capacitor is used on the IC power-supply pins. Typical values of decoupling capacitors are 0.001F and 0.1F. Use a high-quality, ceramic, surface-mount capacitor, and mount it as close as possible to the VCC and GND pins of the IC to minimize lead inductance. fSSO DITHER CYCLE RATE = fDITHER = fIN/992 +1.5% +1.0% +0.5% f0 -0.5% -1.0% -1.5% t Figure 1. Spread-Spectrum Frequency Modulation 6 Maxim Integrated DS1080L Spread-Spectrum Crystal Multiplier Typical Operating Circuit CRYSTAL CL2 CL1 X1 GND CMSEL SMSEL 1 2 8 DS1080L 7 3 6 4 5 X2 VCC VCC SSO DECOUPLING CAPACITOR PDN VCC fSSO NOTE: IN THE ABOVE CONFIGURATION WITH PDN CONNECTED TO VCC, SMSEL CONNECTED TO GND AND CMSEL OPEN, THE DEVICE IS IN NORMAL OPERATION WITH 2x CLOCK MULTIPLICATION, AND SPREAD-SPECTRUM MAGNITUDE OF 0.5%. Layout Considerations As noted earlier, the crystal should be placed very close to the device to minimize excessive loading due to parasitic capacitances. Care should also be taken to minimize loading on pins that could be open as a programming option (SMSEL and CMSEL). Coupling on inputs due to clocks should be minimized. Maxim Integrated Package Information For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 8 SOP U8+1 21-0036 90-0092 7 DS1080L Spread-Spectrum Crystal Multiplier Revision History REVISION NUMBER REVISION DATE 0 11/05 Initial release -- 1 3/06 Changed VIHMIN from 0.7V x VCC to 0.08V x VCC and VILMAX from 0.3 x VCC to 0.2V x VCC in the Recommended Operating Conditions table 2 2 10/09 Changed the part number in the Ordering Information table 1 3 10/11 Updated the Ordering Information table and Absolute Maximum Ratings section; added the land pattern no. to the Package Information table 4 5/12 Clarified SSODC conditions and split limits based upon CMSEL input state 3/13 Updated the voltage ranges in the Absolute Maximum Ratings; changed the supply current parameter from 13mA (max) to 15mA (max) in the DC Electrical Characteristics table; changed the dither rate parameter from fIN/1024 to fIN/992 in the AC Electrical Characteristics table; updated all graphs in the Typical Operating Characteristics section 5 DESCRIPTION PAGES CHANGED 1, 2, 7 3 2, 3, 4 Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. 8 (c) 2013 Maxim Integrated Products, Inc. Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000 Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc. Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Maxim Integrated: DS1080LU/T+A00 DS1080LU+A00