ST STM32F31xx

Operational amplifier (OPAMP)
UM1581
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DocID023800 Rev 1
 The OPAMPs non inverting input can be selected among the list shown by table
below.
 The OPAMPs inverting input can be selected among the list shown by table below.
 The OPAMPs outputs can be internally connected to the inverting input (follower
mode)
 The OPAMPs outputs can be internally connected to resistor feedback output
(Programmable Gain Amplifier mode)
 The OPAMPs outputs can be internally connected to ADC
 The OPAMPs can be calibrated to compensate the offset compensation
 Timer-controlled Mux for automatic switch of inverting and non-inverting input
Table 14: OPAMPs inverting/non-inverting inputs
OPAMP1
OPAMP2
OPAMP3
OPAMP4
Inverting input
PGA
OK
OK
OK
OK
VOUT
OK
OK
OK
OK
IO1
PC5
PC5
PB10
PB10
IO2
PA3
PA5
PB2
PD8
Non-inverting inputs
IO1
PA7
PD14
PB13
PD11
IO2
PA5
PB14
PA5
PB11
IO3
PA3
PB0
PA1
PA4
IO4
PA1
PA7
PB0
PB13
16.2.2 How to use this driver
This driver provides functions to configure and program the OPAMP of all STM32F30x
devices. To use the OPAMP, perform the following steps:
1. Enable the SYSCFG APB clock to get write access to OPAMP register using
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
2. Configure the OPAMP input in analog mode using GPIO_Init()
3. Configure the OPAMP using OPAMP_Init() function:
 Select the inverting input
 Select the non-inverting inverting input
4. Enable the OPAMP using OPAMP_Cmd() function
16.2.3 Initialization and Configuration functions
 OPAMP_DeInit()
 OPAMP_Init()
 OPAMP_StructInit()
 OPAMP_PGAConfig()
 OPAMP_VrefConfig()
 OPAMP_VrefConnectNonInvertingInput()
 OPAMP_VrefConnectADCCmd()
 OPAMP_TimerControlledMuxConfig()
 OPAMP_TimerControlledMuxCmd()