ST STM32F31xx

UM1581
Operational amplifier (OPAMP)
DocID023800 Rev 1
293/584
Function Description
Configure the OPAMP's internal reference.
Parameters
 OPAMP_Selection : the selected OPAMP. This parameter
can be OPAMP_Selection_OPAMPx where x can be 1 to 4 to
select the OPAMP peripheral.
 OPAMP_Vref : This parameter can be:
OPAMP_Vref_3VDDA: OPMAP Vref = 3.3% VDDA
OPAMP_Vref_10VDDA: OPMAP Vref = 10% VDDA
OPAMP_Vref_50VDDA: OPMAP Vref = 50% VDDA
OPAMP_Vref_90VDDA: OPMAP Vref = 90% VDDA
Return values
 None.
Notes
 This feature is used when calibration enabled or OPAMP's
reference connected to the non inverting input.
 If the selected OPAMP is locked, Vref configuration can't be
performed. To unlock the configuration, perform a system
reset.
16.2.4.6 OPAMP_VrefConnectNonInvertingInput
Function Name
void OPAMP_VrefConnectNonInvertingInput ( uint32_t
OPAMP_Selection, FunctionalState NewState)
Function Description
Connnect the internal reference to the OPAMP's non inverting
input.
Parameters
 OPAMP_Selection : the selected OPAMP. This parameter
can be OPAMP_Selection_OPAMPx where x can be 1 to 4 to
select the OPAMP peripheral.
 NewState : new state of the OPAMP peripheral. This
parameter can be: ENABLE or DISABLE.
Return values
 None.
Notes
 If the selected OPAMP is locked, Vref configuration can't be
performed. To unlock the configuration, perform a system
reset.
16.2.4.7 OPAMP_VrefConnectADCCmd
Function Name
void OPAMP_VrefConnectADCCmd ( uint32_t
OPAMP_Selection, FunctionalState NewState)