I attempting to low power solution that interface two pressure sensor (bridge resistance) with sample rate 10Hz for both channel, ie every 100mSec,
0mSec Event Timer my MCU, wake up
0mSec power up pressure sensor (2V5)
5mSec initiate capture both channel (after sensor settle time)
10mSec (ideally) power down pressure sensor
repeat every 100mSec.
Due to a limitation of a digital filter in Sigma Delta especially two channel mux. It requires maximum sample rate to process the job and thus lose the benefits of 24 bits resolution due to GAIN=128V/V and ENOB reduced to 16 bits.
It looks like I may have to use SAR 16 bit because I need to turn off pressure sensor to save power. Can you recommend suitable low power instrument amp or solution with a fixed gain of 100V/V.
It needs to be 125C grade parts. Including chopper/auto-zero.
I'm open for ideas,
