This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TINA/Spice/INA139: Read bipolar current over both positive and negative range.

Part Number: INA139
Other Parts Discussed in Thread: TINA-TI, , OPA197

Tool/software: TINA-TI or Spice Models

Hello,

I'm following up on a previous inquiry related to the INA139 and simulations in TI-TINA.

I'm exploring the device again for another project, but I am once again having issues with the INA139's simulation models.

---

The intention is to use two INA139's in a bipolar configuration to measure the bidirectional current across a range of +12 V to -12 V. I realize that the common-mode range must be observed when dealing with the current measurement, thus I have elected to attach "GND" of the INA139 to the -12V rail, and Power the "V+" of the INA139 from the +12V rail.

This should keep the common mode between 2.7V and 40V referenced to the negative rail.

What I would like to do is feed this value into a difference amplifier similar to 8.2.5 Bipolar Current Measurement Using a Differential Input of the A/D Converter in the INA139 datasheet, but I cannot see to get this working in my simulations. I am using an OPA197 as the amplifier.

Any help would be appreciated.

Thanks,