Forum Post: RE: Weird Conversion with ADS62P44

Hi,

Can you please measure VCM of ADS62P44 device? It should be 1.5V with internal reference mode. When external reference mode, the differential input voltage corresponding to full-scale is given in equation 2 shown as below from datasheet,

Full-scale differential input pp = (voltage forced on VCM) x 1.33

In this mode, 1.5V common mode voltage to biad the input pins has to be generated externally.

With two's complement format, you should have sampled output ranging -8192 to 8191.

Thanks,

KW