INA190: combining multiple shunts

Rosario Gandolfo

Part Number: INA190

Tool/software:

Hi team,

I have a question regarding INA190A5.

I need a current measurement range from a few uA to 5A. To cover the wide current range, Is is possible to daisy-chain several shunt resistors in combination with the INA device?
Is it technically possible and do you know any circuit options to short a shunt once the current on a shunt is too large?

Are there other ways to cover such a large measuring range?

I could also accept a voltage drop of up to 100 mV on the supply line.

Best regards,

Rosario

3 months ago

0 Joe Vanacore 3 months ago

TI__Genius 17360 points

Hello Rosario,

Thank you for your post.

I will provide you with a response tomorrow.

Thank you for your patience,

Joe

0 Rosario Gandolfo 3 months ago in reply to Joe Vanacore

TI__Intellectual 2430 points

Hi Joe,

thank you for your quick response!
Lookin forward to your response.

Best regards,

Rosario

+1 Joe Vanacore 3 months ago in reply to Rosario Gandolfo

TI__Genius 17360 points

Hello Rosario,

Yes, placing multiple shunt resistors in series is completely acceptable.

Please see this post for additional confirmation: (+) INA199-Q1: Two shunt resistors for INA199B1DCKRs - Amplifiers forum - Amplifiers - TI E2E support forums

In terms of disabling the shunt resistors... this will be more difficult than processing downstream with a microprocessor. I would suggest using a comparator to monitor the current (potentially INA310 that has output and CMP output) and pass this to a microprocessor for output signal selection.

You can also use a mux controlled by the comparator output of the INA310.

This is the way I would address it.

Please let me know your thoughts on this.

I hope this helps,

Joe