INA210: Schematic Review

Hi Kevin,

the INA210 has a voltage output and should not have a capacitive load of 22nF. Datasheet says that the maximum capacitive load is 1nF.

Why do you want to connect a cap to the output?

Kai

Dear Kai,

Thanks for remind.

How about V+ pin, is it necessary to use LDO here?

Currently the customer is using buck here.

BR

Kevin

Hi Kevin,

the voltage output Vout swings from GND to V+. So, if you connect Vout to the input of a microcontroller which is supplied by 3.3V, then it makes sense to also supply the INA210 by 3.3V. The 3.3V supply voltage should be clean and free from any switcher ripple.

Kai

Hi Kevin,

Besides what you and Kai already discussed, you might want to see if the swing to ground limit of 50mV satisfies the requirement coming from the smallest current to be measured. In addition “offset X gain” should be added on top of the 50mV.

Regards, Guang

Dear All,

Thanks for the help!

Do you mean the 35uV*200=7mV for maximum output offset?

I am not sure what do you mean 50mV here.

Besides, will you suggest reserve output pin have a resistor for RC filter?

(Fc : 1/2pi*R*C), if yes what is the Fc you will suggest?

BR

Kevin

Hi Kuan,

Guans means that the output of INA210 cannot fully go down to GND:

Kai

Hi Kevin,

To you question regarding Fc - It depends on the speed requirement of the application. If full bandwidth is not required such as in DC measurements, then Fc can be placed as low as practical, at a few KHz for example. As Kai replied previously, R is required, not optional, with the capacitor shown for stability reasons.

Thank you Kai for your inputs.

Regards, Guang