LTC6909 1 to 8 Output, Multiphase Silicon Oscillator with Spread Spectrum Modulation Fe A Description n 1-, 2-, 3-, 4-, 5-, 6-, 7- or 8-Phase Outputs The LTC 6909 is an easy to use precision oscillator that n One External Resistor Sets the Output Frequency can provide 1-, 2-, 3-, 4-, 5-, 6-, 7- or 8-phase synchro- from 12.5kHz to 6.67MHz nized outputs. The LTC6909 also offers spread spectrum n frequency modulation (SSFM), which can be enabled to im- Optional Spread Spectrum Frequency for Improved prove electromagnetic compatibility (EMC) performance. EMI Performance n 10% Frequency Spreading Eight separate outputs provide up to eight rail-to-rail, n Outputs Can Be Held Low or Floated (Hi-Z) 50% duty cycle clock signals. Using three logic inputs, the n Three Spread Spectrum Modulation Rates outputs are configured for phase separation, ranging from f /16, f /32 and f /64 OUT OUT OUT 45 to 120 (three to eight phases). The clock outputs can n 400A Supply Current also be held low or configured for Hi-Z. A single resistor, n Operates from a Single 2.7V to 5.5V Supply combined with the phase configuration, sets the output n Fast Start-Up Time frequency, based on the following formula: n First Cycle Accurate f = 20MHz 10k/(R PH) n OUT SET Outputs Are High Impedance Until Frequency Settles n MS16 Package where PH = 3, 4, 5, 6, 7 or 8 The LTC6909 can be used in applications requiring only Applic A one or two output phases. Alternatively, the LTC6908 family of parts provides the same two output signals but n Synchronizing Multiple Switching Power Supplies in a smaller SOT-23 or 2mm 3mm DFN package. The L, LT, LTC, LTM, Linear Technology, the Linear logo and Module are registered trademarks LTC6908-1 provides complimentary (180) outputs while and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6342817, 6614313, the LTC6908-2 provides quadrature (90) outputs. 7417509. t Al Applic A 150kHz to 30MHz Output Frequency Spectrum (9kHz Res BW) Providing a 4-Phase Synchronizing Clock to LTM Modules 0 SSFM DISABLED 10V TO 14V 10 INTV 20 CC S0FT-START 0.1F LTM4601 LTC6909 30 + V D OUT1 1.5V 40 48A GND OUT2 TRACKING + 50 LTM4601-1 V A OUT3 71.5k SET OUT4 0.1F 0 SSFM ENABLED PH0 OUT5 TRACKING 10 SSFM = f /32 OUT LTM4601-1 PH1 OUT6 20 PH2 OUT7 30 MOD OUT8 TRACKING LTM4601-1 40 50 6909 TA01 ENABLE SSFM DISABLE SSFM 150kHz 30MHz FREQUENCY 0.01F (FUNDAMENTAL AND HARMONICS SHOWN) 6909 TA01b 6909fa 1 OUTPUT (dBc) OUTPUT (dBc) tion ypic tions turesLTC6909 Absolute M A Mu M rA p in c F A (Note 1) + TOP VIEW Supply Voltage (V A) to GND ......................................6V + + V A 1 16 SET Supply Voltage (V D) to GND ......................................6V GND 2 15 PH2 PH0 3 14 MOD Maximum Voltage + PH1 4 13 V D + OUT1 5 12 OUT8 on Any Pin ................ (GND 0.3V) V (V + 0.3V) PIN OUT2 6 11 OUT7 Operating Temperature Range (Note 2) OUT3 7 10 OUT6 OUT4 8 9 OUT5 LTC6909C ............................................40C to 85C MS PACKAGE LTC6909I .............................................40C to 85C 16-LEAD PLASTIC MSOP T = 150C, = 125C/W JMAX JA LTC6909H .......................................... 40C to 125C Specified Temperature Range (Note 3) LTC6909C ................................................ 0C to 70C LTC6909I .............................................40C to 85C LTC6909H .......................................... 40C to 125C Junction Temperature ........................................... 150C Storage Temperature Range .................. 65C to 150C Lead Temperature (Soldering, 10 sec) ...................300C o r Der i n F MA LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION SPECIFIED TEMPERATURE RANGE LTC6909CMS PBF LTC6909CMS TRPBF 6909 16-Lead Plastic MSOP 0C to 70C LTC6909IMS PBF LTC6909IMS TRPBF 6909 16-Lead Plastic MSOP 40C to 85C LTC6909HMS PBF LTC6909HMS TRPBF 6909 16-Lead Plastic MSOP 40C to 125C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: