ADC3910S025: vcm impedance, data alignment

John Larkin

Part Number: ADC3910S025

Tool/software:

What is the output impedance/current drive capability of the Vcm output?

I assume I can ignore the SPI interface, hardware reset it, and use it as a plain 10-bit parallel ADC, in its default mode. Is that OK?

If so, where do the 10 data bits come out? There are 12 pins, D0 through D11.

1 month ago

0 Rob Reeder 1 month ago

TI__Mastermind 41280 points

Hi John,

The VCM output drive strength is not very good on any ADC. If you plan to connect the VCM output to an amplifier that is close by, you should be fine.

Otherwise, use a follower buffer to keep the voltage solid. I would place a 0.1uF cap both at the VCM output, near the ADC and near the amplifier input, VOCM pin.

In terms of the 10bits vs. 12bit. MSB justify and use D11 and down...first 10 output bits.

Regards,

Rob