RTOS/INA223: Vout range at INA223 and total current shunt monitor solutions

Hello Hugo,

Thanks for coming to the forum.

The output voltage range (Vout) of INA233 limited by its "Swing to VS-Power Supply Rail", "Swing to GND", and input offset specifications.

The first two specifications show how close the amplifier can swing to its voltage supply rails, but "Swing to GND" is based on an over driven condition. In other words, the swing-to-rail specifications don't necessarily reflect the linear output range of the amplifier. The linear range of the amplifier can be determined by looking at the gain error specification testing condition which shows 10mV to 155mV input sense voltage for gain =20V/V.

I mentioned offset earlier because if there is zero load-current is flowing (VSHUNT=VSENSE=0), then VOUT could be the “Swing to GND” value, but it also could be the input offset (Vos_total) multiplied by the gain of amplifier. This happens when the total input offset is positive causing it to by gained up and shows up on VOUT. You can read more about output specifications, how to calculate total offset, and general current sensing educational material in the links below.

e2e.ti.com/.../703088
training.ti.com/getting-started-current-sense-amplifiers
training.ti.com/ti-precision-labs-op-amps

Hope this helps.

Sincerely,
Peter Iliya
Current Sensing Applications