ADS1259: 2 ADCs with same internal oscillator

Hi Bryan,

Could you recommend a cost-effective device to use as an external clock?

The recommended frequency is very specific (7.3728MHz).

Thanks,

Max

Hi Max,

Are you not able to use the ADS1259's internal oscillator? That would be the cheapest option

Here is a list of possible clocks from digikey: https://www.digikey.com/short/zjzv5q  

The 7.3728 MHz clock frequency is the nominal value to realize the data rates specified in the ADS1259's datasheet. But you can use any value from 0.1 to 8 MHz, as shown below. The data rates would then scale with the clock frequency used.

-Bryan

Hi Bryan,

Thanks for your answer.

Yes, we want to use the internal oscillator but with both ADCs synchronized, that's the purpose of my post. I need to capture both signals with the best possible synchronization.

I think that the +/-2% tolerance of the internal clock could be good enough, but I wanted to avoid it because it adds to 4% max error.

Max

Hi Max,

Understood, thanks for getting back to me.

To minimize error and ensure synchronization, I agree it would be best to use an external oscillator. But it is understandable that this must be balanced with the cost and complexity of the system.

-Bryan