INA226-Q1: In case of using with isolator

Chase Jeong

Mastermind 7505 points

Part Number: INA226-Q1
Other Parts Discussed in Thread: INA381

Tool/software:

Dear TI experts,

My customer wants to use INA226-Q1 with isolator in front of the input.

In case of this, sensing speed would be lower because if isolator? or error rate would be increased?

Please check this issue. Thanks,

Best regards,

Chase

3 months ago

0 Clemens Ladisch 3 months ago

Guru 316920 points

The speed of the INA226-Q1 itself would not be affected. I do not know how the unknown isolator would affect the input signals.

Would it be possible to put the INA226-Q1 on the other side, and to isolate the I²C signals instead?

0 Mitch M 3 months ago

TI__Mastermind 26205 points

Hello Chase,

I agree with Clemens, it would be better to add the isolator on the I2C signals. Here are a couple example designs that do this:

https://www.ti.com/tool/TIDA-00313

https://www.ti.com/tool/TIDA-01608

Or, you could use a device that has isolation built in:

Isolated Amplifiers: https://www.ti.com/isolation/isolated-amplifiers/overview.html

Isolated ADCs: https://www.ti.com/isolation/isolated-adcs/overview.html

Regards,

Mitch

0 Chase Jeong 3 months ago in reply to Mitch M

Mastermind 7505 points

Dear Clemens, Mitch,

Thank you for your support.

For now, they are using INA381 for high voltage current sensing, And they are planning to move this part to low voltage block.

So I think it is not possible to use isolator on the I2C signal lines.

Could you recommend any isolators for the right purpose?

Please check this issue. Thanks.

Best regards,

Chase

0 Mitch M 3 months ago in reply to Chase Jeong

TI__Mastermind 26205 points

Hey Chase,

If you are wanting an analog part with isolation, then you would be better off using an isolated amplifier, from the link in my previous post. I am not familiar with the specific isolator products, so I'll forward this thread to the isolated amplifier team for your part recommendation.

Regards,

Mitch

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INA226-Q1: In case of using with isolator