Inverting PGA

For inverting programmable gain amplifier operation, the OPAMPCTRLx registers can be configured as follows:

Table 1. Configuration - Three Independent Inverting PGAs
  MUXPOS MUXNEG RES1MUX POTMUX RES2VCC RES2OUT RES1EN ANAOUT
OPAMP0 011 001 01 100 0 1 1 0
OPAMP1 011 001 01 100 0 1 1 0
OPAMP2 011 001 01 100 0 1 1 0

Inverting PGA (Example: Vout=-3.Vin, R1=4R, R2=12R)

Figure 1. Inverting PGA