ltc6902cms-trpbf Linear Technology Corporation, ltc6902cms-trpbf Datasheet
ltc6902cms-trpbf
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ltc6902cms-trpbf Summary of contents
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... The amount of frequency spreading is programmable by a single additional external resistor (R ) and is disabled by grounding the MOD pin. MOD , LTC and LT are registered trademarks of Linear Technology Corporation. Output Frequency Spectrum With and Without SSFM OUT4 OUT3 OUT2 OUT1 ...
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... Pin 3 = Open (3-Phase Pin (4-Phase Pin Pin (2-Phase Pin 3 = Open (3-Phase Pin (4-Phase ORDER PART NUMBER 10 SET LTC6902CMS 9 MOD 8 GND LTC6902IMS 7 OUT4 6 OUT3 MS PART MARKING LTK2 = 250 C/W JA LTK3 = 5pF, Pin 3 (PH (2-phase ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T unless otherwise specified. Pin 9 (MOD unless otherwise specified the V pin defined as a resistor connected from the MOD pin to the ...
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... Note 9: The LTC6902CMS and LTC6902IMS are guaranteed functional OUT over the operating temperature range of – Note 10: The LTC6902CMS is guaranteed to meet specifica- tions and are designed, characterized and expected to meet the specified performance from – but is not tested or QA sampled at these temperatures. The LTC6902IMS is guaranteed to meet specified perfor- mance from – ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Output Operating at 20MHz 5V 10k, C SET 1V/DIV 0V 12.5ns/DIV U QUICK DESIG GUIDE + V R MOD 0 SET LTC6902 ...
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LTC6902 U QUICK DESIG GUIDE Step 3. Calculating the R Resistor Value SET The R resistor, the multiphase mode and the divider SET setting set the output frequency (f quency applications. For SSFM applications, the maxi- mum frequency excursion (f ...
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CTIO should be surrounded by a ground shield to prevent excessive coupling from other PCB traces. OUT1, OUT2, OUT3, OUT4 (Pins and 7): Oscillator Outputs. These pins can drive ...
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LTC6902 THEORY OF OPERATIO As shown in the Block Diagram, the LTC6902’s master oscillator is controlled by the ratio of the voltage between + + the V and SET pins (V – and the current entering SET the ...
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THEORY OF OPERATIO divider goes through further division. In addition to fur- ther division, the duty cycle of the output depends on the multiphase mode selected. Figure 4 shows the waveform at each output for 2-, 3- and 4-phase modes. ...
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LTC6902 THEORY OF OPERATIO by 90 degrees, OUT3 lags OUT2 by 90 degrees and OUT4 lags OUT3 by 90 degrees. The signals are generated by flip-flops. The output frequency is the programmable divider’s output further divided 4). ...
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THEORY OF OPERATIO clock cycle. Note that the shift register clock is the master oscillator’s output divided by 3200. This results in a some- what slow moving modulating signal where each step is separated in time by 3200/f seconds and ...
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LTC6902 U U APPLICATIO S I FOR ATIO Table 1. Recommended Frequency Range vs Programmable Divider Setting for SSFM Applications or for Low Jitter Constant Frequency Applications DIVIDER SETTING FREQUENCY RANGE ( DIV (Pin 2) = GND ...
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U U APPLICATIO S I FOR ATIO spreading is determined, the R MOD using the simple equation below: R SET R 20 • MOD Spreading Percentage The only limitations for this formula are in the R range and the spreading ...
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LTC6902 U U APPLICATIO S I FOR ATIO generator is driven by the master oscillator frequency, not the output frequency. This gives some design flexibility in the choice of the R and the programmable divider SET setting. When making the ...
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... SUPPLY VOLTAGE (V) Figure 6. Supply Sensitivity Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights independent from the setting of the divider pin. For in- stance with R of its 200kHz final value (N = 10) in approximately 380 s ...
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... RELATED PARTS PART NUMBER DESCRIPTION TM LTC1799 1kHz to 30MHz ThinSOT LTC6900 1kHz to 20MHz ThinSOT Oscillator ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 16 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 U MS Package 10-Lead Plastic MSOP (Reference LTC DWG # 05-08-1661) ...