ADS7830: ADS7830 application to monitor 12V

We are looking into this, and will get back to you soon, Regards Cynthia

Hi Ann

Yes ADS7830 can be use to monitor 12V rail. You need to scale down 12V line to match ADS7830 full scale voltage range.

ADS7830 input voltage range is dependent on its reference voltage. If you are using ADS7830 internal reference then device input range is 0V to 2.5V.
If you are using external reference then ADS7830 input voltage range is from 0 to VREF (VREF can be from 50mV to VDD).

Can you please let me know what is the end application here. This is a 8 channel device. Do you plan to monitor any other rails in the system or you just need to monitor 12V.

Thanks & Regards
Abhijeet

If I design my schematic as below, it should be OK to monitor the 12V correct?

Hi Anne

The arrangement to monitor 12V rail looks ok.
I would like to check what are the voltage rails on the other input channels, especially P3V3 and P3V3_AUX. If you are using internal reference (2.5V) then ADC full scale input range is from 0 to VREF that is 0 to 2.5V. You will see saturated ADC code.

If you plan to monitor 3.3V rail directly then you can either use external reference >3.3V and VDD>3.3V to get correct ADC reading. The other way is to use resistive divide on 3.3V rail similar to one used on 12V rail to get the input within ADC full scale range

Thanks & Regards
Abhijeet