For INA2xx power sensors (INA226 specificly) may I use resistive divider for more voltage

Other Hardware Sensors
1

I need to use this INA 2xx power sensors on a project with ESP32. But I have a bus voltage more than 36V (which is the max limit of INA226), there is a INA238 for 85 V which is enough for my project.

But the thing is there is literally no code source (library) on the web for ina238 but there are lots of libraries for INA226. So I am planning to use a basic voltage division (like 1 to 3) with resistors to have a bus voltage less than the max limit of INA226 and then multiply it by three in the software. Is this a logical solution for this problem? It should be basic and simple as that right just I will divide my real Vbus and feed it like a fake Vbus to the sensor, all other connections and logic should be the same

2

Are you using the IC or a module?
Do you also want to measure current?

3

WhatsApp Image 2025-01-10 at 12.23.09
WhatsApp Image 2025-01-10 at 12.23.091466×870 426 KB

I am using the IC itself and need to measure current I was planning to do this.

4

The common voltage on Vin+ and Vin- must be less than 40V and you have greater than than on the INA226 on the left (Input). So that is no good
I have no idea what you are trying to do with the buck

5

Is the INA228 an option? it supports 85Volts.

It might be possible to derive an INA238 library (needs investigation)

6

I am trying to build a MPPT (input is solar panel output is heater) with the buck but I need power measurements from input and output side. What is your suggestion?

7

Depends on the maximum voltages and currents you are trying to measure, you never said.

8

It will be safe to say that input is 100V 5 A and Output will be probably around lower Voltage Higher Current

9

You can use this to measure current on the high voltage side

and just use a voltage divider to measure the voltage.

Same can be done for the lower voltage side. Pololu has a bunch of different current sensor modules for different current ranges

10

In case you can get the INA238, Could you try with this library? I need to add the part of the DIAG_ALRT Register, but first I would like to know if it possible to make some measurements using this library.
Unfortunately I don't have the device and it is somewhat difficult for me to get it.

11

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