Part Number: MSPM0G3507
Other Parts Discussed in Thread: SYSCONFIG
I'm trying to measure differential voltage of current sense resistor in a 3.3V line (same supply as MSPM0G MCU). I want it to act like a simple current-sense amplifier, with 32x gain, read by internal ADC. V1 will be source side, and V2 will be on the load side of the current sense resistor. I followed the design from reference manual:
I have a few questions regarding parameters in Sysconfig.
OPA_0: acting as the left OPA in above schematic
PSEL (non inverting channel) = IN0+ pin
NSEL (Inverting channel) = OPA[x-1]_RBOT
MSEL (Input MUX) = open
Gain = (how should I set the gain for this OPA_0?)
Enable OPA Output Pin = output disabled
Chopping Configuration = ADC Averaging
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OPA_1: acting as the right OPA in above schematic
PSEL (non inverting channel) = IN1+ pin
NSEL (Inverting channel) = RTAP
MSEL (Input MUX) = OPA[x-1]_RTOP
Gain = Non-Inverting: 32x / Inverting: -31x
Enable OPA Output Pin = output disabled (ADC channel 13 will read the output)
Chopping Configuration =ADC Averaging
The only problem as much as I understand, is the gain selections in Sysconfig for OPA_0. Is the total gain set in options for OPA_1? What should I enter for OPA_0 gain option (default is Non-Inverting: Not vaild / Inverting: Not valid)?
