Figure 172. Pga Mode, Non-Inverting Gain Setting (X2/X4/X8/X16/X32/X64); Or Inverting Gain Setting (X-1/X-3/X-7/X-15/X-31/X-63) - ST STM32G4 Series Reference Manual

RM0440
Programmable gain amplifier, non-inverting with external bias
The procedure to use the OPAMP to amplify the amplitude of an input signal with bias
voltage for non-inverting mode or inverting mode.
•
configure VM_SEL bits as "Feedback resistor is connected to OPAMPx_VINM input",
10
•
configure PGA_GAIN bits as "Inverting gain = -1, -3, -7, -15, -31, -63 / Non-inverting
gain =2, 4, 8, 16, 32, 64 with VINM0", 01000 to 01101
• configure VP_SEL bits as "GPIO connected to OPAMPx_VINP".

Figure 172. PGA mode, non-inverting gain setting (x2/x4/x8/x16/x32/x64)

VINP3 or DACx_CHy
1. opamp_out can be redirected internally to an ADC channel by setting OPAINTOEN bit.
In this case, the I/O on which is mapped the OPAMPx_VOUT is free and can be used for another purpose.
Programmable gain amplifier, non-inverting with external bias
The procedure to use the OPAMP to amplify the amplitude of an input signal with bias
voltage for non-inverting mode or inverting mode with filtering
• configure VM_SEL bits as "Feedback resistor is connected to OPAMPx_VINM input",
10
•
configure PGA_GAIN bits as "Inverting gain= -1, -3, -7, -15, -31, -63 / Non-inverting
gain =2, 4, 8, 16, 32, 64 with VINM0, VINM1 pin for filtering", 11000 to 11101
•
configure VP_SEL bits as "GPIO connected to OPAMPx_VINP".
Any external connection on VINM1 can be used in parallel with the internal PGA, for
example a capacitor can be connected between opamp_out and VINM1 for filtering
purpose (see datasheet for the value of resistors used in the PGA resistor network).
or inverting mode

or inverting gain setting (x-1/x-3/x-7/x-15/x-31/x-63)

STM32
VINP0
VINP1
VINP2
VINM0
VOUT
or inverting mode with filtering
+
-
RM0440 Rev 1
Operational amplifiers (OPAMP)
opamp_out
(1)
MSv48043V1
751/2083
787