INA381: Electrical characteristics conformity over lifetime use (input referred offset)

Erik Jarva

Part Number: INA381

I am interested in using the INA381 current sense amplifier as part of a product where the design of the system relies on the small signal output of the amplifier.

Is there information regarding the input referred offset band over the lifetime of the product?

Is there any guarantee of maximum offset levels during operation?

over 2 years ago

0 Javier Contreras4 over 2 years ago

TI__Mastermind 26475 points

Hello Erik,

During the lifetime of the product the specifications on the datasheet should be valid. The maximum offset is listed in the datasheet under the global conditions unless otherwise noted. You can calculate your expected max offset by using your conditions and how they differ from the test conditions listed in the datasheet. For the INA381 the max offset at 12V VCM is 500µV while at 0V VCM the offset is 150µV. The training material below goes through the calculations if needed for other VCM or other changes such as temperature or power supply voltages.

https://training.ti.com/ti-precision-labs-current-sense-amplifiers-reading-current-sense-amplifier-datasheets

https://training.ti.com/ti-precision-labs-current-sense-amplifiers-offset-error

https://training.ti.com/ti-precision-labs-current-sense-amplifiers-error-sources

Regards,

Javier

0 Erik Jarva over 2 years ago in reply to Javier Contreras4

Prodigy 10 points

Hello Javier,

Thank you for the links. My interest is in the maximum offset of the device throughout the individual component's lifetime use.

Are the measurements used to determine the maximum values taken from new components or from components that have been stressed or aged to simulate degradation of the parts?

To put it another way, is there an implicit guarantee that the bounding values in the datasheet will remain applicable for the component after several years of use?

Thanks again,

Erik

+1 Javier Contreras4 over 2 years ago in reply to Erik Jarva

TI__Mastermind 26475 points

Erik,

Yes the device will function as the spec from the datasheet and we do test devices that are stressed to determine this over the lifetime. Please see this link: https://www.ti.com/support-quality/reliability/reliability-testing.html.

If you would like a more robust solution you can use an automotive qualified device which goes through a more robust qualification and screening. https://www.ti.com/product/INA381-Q1

Each device could have multiple qualifications as they meet may need to meet different needs. For each device you can verify what test have been done from the quality information seen from the Product Specific page at the very bottom is the links.

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INA381: Electrical characteristics conformity over lifetime use (input referred offset)