For inverting programmable gain amplifier operation, the OPAMPCTRLx registers can be configured as follows:
MUXPOS | MUXNEG | RES1MUX | POTMUX | RES2VCC | RES2OUT | RES1EN | ANAOUT | |
---|---|---|---|---|---|---|---|---|
OPAMP0 | 0010 | 001 | 001 | 100 | 0 | 1 | 1 | 0 |
OPAMP1 | 0010 | 001 | 001 | 100 | 0 | 1 | 1 | 0 |
OPAMP2 | 0010 | 001 | 001 | 100 | 0 | 1 | 1 | 0 |
Inverting PGA (Example: Vout=-3.Vin, R1=4R, R2=12R)