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INA3221: Minimum Supply Voltage

Part Number: INA3221
Other Parts Discussed in Thread: INA216, INA231

Hi E2e, 

I've been using the INA3221 in a battery powered device and it seems working well with a voltage supply below the specified minimum voltage of +2.7V. I've even tested the device with a supply voltage of 2.3V and it is still working.

I'm wondering if it is a good practice to power the INA3221 with voltage below the specified +2.7V? Is there any drawback?

Note that the chip isn't going to measure voltage above its power supply.

In case its really not a good pratice, is there a product like the INA3221 which is specified with a lower supply voltage. 

Thanks in advance for your advice. 

Darko

  • Hello Darko,

    Thank you for your interest in Texas Instruments' INA3221.  We do not believe it is good practice for you to power INA3221 below the specified +2.7V.  The device you have now may work with a 2.3V supply, however we expect that if you purchased a large volume of these parts, there would be several that would not be able to function properly with that supply.  This can be attributed to manufacturing variation.  As such we only guarantee that our parts will function as expected within the recommended operating range listed in the Datasheet.

    As for finding an alternative to the INA3221, we do not have another digital multi-sensor solution.  However, we do have the INA231 which has one current or power monitor and is compliant with 1.8V I2C signals.  Yet this part also requires a minimum of 2.7V supply.  If you did not need a digital solution, you may also consider using some INA216s with a multi-channel ADC.  The INA216 can run off a supply as low as 1.8V.

  • Hi Darko,

    As an alternative you could consider boosting the INA3221 supply voltage using a simple charge pump IC such as the LM2767.