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Design help

Category: Hardware
Product Number: LTC6930

I am replacing a now obsolete EPSON CMOS oscillator that served as the primary clock in a dual axis stepper motor design for over 15 years. The primary clock frequency is 32.768kHz --- we wish to use the Linear Tech LTC6930 to divide down its internal 4.192Khz by 128 and use the the resulting 32.768kHz as our new primary clock signal.

We will be driving a pair of AD9833 DDS waveform generators which operate as stepper clocks for 2 independent stepper drivers.

1. To your knowledge, will the LTC6930 operate with the AD9833 in a single 5V supply environment? 

2. Will the LTC6930 drive two AD9833 devices directly without issue, or should I add a series resistor from the LTC6930 output to each AD9833 input?

3. If resistors are required, what would the appropriate value be --- (470 Ohm, 1K, 10K, etc;) ?

4. The approximate distance from the primary clock output to the AD9833s is 1.48 inches for the farthest unit and 0.498 inches for the closest unit with lots of ground plane all around.

Any suggestions or recommendations greatly appreciated .

Best regards,

Randy