I'm making a low power weighing scale with good precision. I'm contemplating if it'll be better to build a instrumentation amplifier with discrete OPAMPs of LPV821 which is low power (Iq 650 nA), high precision (Vos 2 uV typical, 10 uV max) and CMRR of 125 dB typical.
The other option is to use an instrumentation amplifier like INA333, which has characteristics like Iq of 50 uA, Vos of 10 uV typical, 25 uA max, and CMRR of 115 dB. I understand the laser trimmed resistances in the INA333 would make the gain precise.
What pros and cons should I consider for the two approaches? Thanks!