INA213-Q1: calculation of worst-case current sensing figures

Josef Warta

Part Number: INA213-Q1

Hello Team, enclosed question from customer to INA213AQDCK:

Could you please provide detailed formulas on how to estimate worst-case current sensing figures using INA213AQDCK including all error margins?

Many Thanks

Josef

0 Levi Devries 4 months ago

Josef,

We actually have a tool that will calculate the total error for our parts here: https://www.ti.com/tool/CS-AMPLIFIER-ERROR-TOOL

Additionally, a subsection of our video series is devoted to error calculation: https://www.ti.com/video/series/precision-labs/ti-precision-labs-current-sense-amplifiers.html (look for the third section on the right, titled "error sources")

Let me know if you have any more questions that are not answered by these resources!

Levi DeVries

0 Josef Warta 4 months ago in reply to Levi Devries

Hello Levi, enclosed additional questions:

In order to estimate input filter impact on input offset voltage, internal bias resistance is required (snapshots below).

Since it is not provided in INA213AQDCK datasheet, could you please help with this matter?

Many Thanks

Josef

0 Levi Devries 4 months ago in reply to Josef Warta

Hello Josef,

For the INA213-Q1, the R_BIAS can be inferred from equation 1 of the datasheet as twice the value used (1250):

so R_BIAS will be 2.5kΩ for you.

Let me know if you have any more questions,

Levi DeVries

0 Hachim Hjira 4 months ago in reply to Levi Devries

Hello Levi,

Thank you for the feedback.

Moreover, what would be the tolerance of the said resistance (typical 30%)?

Best regards,

Hachim

0 Levi Devries 4 months ago in reply to Hachim Hjira

Hello Hachim,

The tolerance for the INA213-Q1 is 30% for all of the internal resistors, as mentioned in the datasheet section on input filtering.

Let me know if you have any more questions,

Levi DeVries

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