TINA/Spice/ADS8325: Input Circuit TINA Simulation

Hello,

Unfortunately there is not a TINA spice model for this device.

To verify that an input driving circuit can drive the SAR, you can create the sample and hold circuitry of the SAR. There is a video in TI Precision Labs that can walk you through creating this: SAR ADC Input Driver Design

For the ADS8325, the internal sample and hold cap is 25pF, the minimum acquisition time is 3 CLK cycle, and maximum conversion time is 12 CLK cycles. I would suggest using the fastest clock to measure for worst case.

Also what is helpful is the Analog Eng Calculator, to start your search for a driving amplifier.

Inputting the information into the ADC SAR Drive section, this will give you acceptable RC values and a bandwidth requirement of 10MHz bandwidth for the driving amplifier

Regards, Cynthia