se00an
Newbie level 1
how to measure dc voltage in adc converter
Hi,
I am a student currently working on building a hybrid racecar for Rensselaer Polytechnic Institute. According to the rules, the high voltage circuit must be electrically isolated from the control circuit. We need to measure the battery voltage, and I was thinking of using the popular ISO124 isolation amplifier. This is powered from both sides, and isolates an input voltage from the proportional analog output voltage. Our HV battery will be about 120 volts, which I will scale down with a voltage divider before putting it into the ISO124. This chip's datasheet in the example states that is powered by +15v and -15v on either side. It will be much easier if I could only use positive voltage on either side, especially that I am not going to measure negative battery voltage levels at all. Do I really need to supply both + and - voltage on both sides, or would it be OK if I connected the -voltage terminal to ground?
The datasheet with example circuits is here: https://focus.ti.com/lit/ds/symlink/iso124.pdf
Thanks very much!
Sean Michnowski
Hi,
I am a student currently working on building a hybrid racecar for Rensselaer Polytechnic Institute. According to the rules, the high voltage circuit must be electrically isolated from the control circuit. We need to measure the battery voltage, and I was thinking of using the popular ISO124 isolation amplifier. This is powered from both sides, and isolates an input voltage from the proportional analog output voltage. Our HV battery will be about 120 volts, which I will scale down with a voltage divider before putting it into the ISO124. This chip's datasheet in the example states that is powered by +15v and -15v on either side. It will be much easier if I could only use positive voltage on either side, especially that I am not going to measure negative battery voltage levels at all. Do I really need to supply both + and - voltage on both sides, or would it be OK if I connected the -voltage terminal to ground?
The datasheet with example circuits is here: https://focus.ti.com/lit/ds/symlink/iso124.pdf
Thanks very much!
Sean Michnowski