Can I use ADA4528 as current monitor circuit or is there a better choice?
Here's a deal.
I wanted to use the ADA4522 (Figure 84 in datasheet), but it has a minimum power supply threshold of 4.5 V. My ADC can handle a maximum of 3 volts.
So I find quite similar OpAmp with 2.5-5.5V power supply voltage - ADA4528.
Сan 4528 be used in the same scheme as 4522?
(Parameters: Rs=10 mOhm, max load less than 5 Amps, R1,R3=1k, R2,R4=50k, so Gain is 50, up to 2.5V to ADC)
The ADA4528 would be a better choice for this application, since it has a much lower offset voltage and noise voltage density to allow higher precision.
You have to keep in mind that the ADA4528…
You have to keep in mind that the ADA4528 has a lower chopping frequency of 200KHz vs the 800KHz chopping frequency of the ADA4522. You've mentioned that you're targeting a gain of 50, now by using the ADA4528 (GBW = 3MHz) your bandwidth of operation would be around 60KHz. Although a 60KHz bandwidth is modest enough to remove the switching artifact from the 200KHz chopping frequency, it would still be a good idea to design your amplifier with a gain such that your bandwidth of operation is under 1 decade of the chopping frequency. So for a 200KHz chopping frequency, a 20KHz bandwith would be a better choice.
Lastly, if your designed isn't constrained on supply current, I suggest you lower your input resistors (R1 and R3) to a value below 1K. This is to preserved the low noise characteristic of the chip.
Thanks a lot!