ST STM32H723, Getting Started, Page: 24 / 50

4 Alternate function mapping to pins
To effectively explore the alternate peripheral function pin mapping refer to the STM32CubeMX tool available on
www.st.com website.
4.1 Analog inputs for ADC1, ADC2 and ADC3
The STM32H723/33, STM32H725/35 and STM32H730 microcontrollers embed four pads with a direct connection
to the ADC (PA0_C; PA1_C; PC2_C; PC3_C).
It avoids the parasitic impedances of a conventional pad and thereby enhancing the performance of the ADC.
Figure 12. Analog inputs for ADC1 and ADC2 shows the pad schematic (also available in the reference manual
STM32H723/733, STM32H725/735 and STM32H730 advanced Arm
®
-based 32-bit MCUs (RM0468)).
Figure 12. Analog inputs for ADC1 and ADC2
Output Driver
Input Driver
From on-chip peripherals
Push -Pull
Open Drain
Disabled
Bit Set/Reset
register
Read / Write
Alternate Function Input
Alternate Function Output
Schmitt
Trigger
Read
Write
Analog
P
A0
P
A1
PC2 PC3
VSS
GPIO
P
A0_C
P
A1_C
PC2_C PC3_C
PxySO bit in
SYSCFG_PMCR
(reset state: closed)
MODERy [1:0] in
GPIOx_MODER
(reset state: open)
To ADC
From analog peripherals
On/off
VDD
VSS
Pull-up
On/off
Pull-down
VDD or
VDD_FT
(1)
OUTPUT
CONTROL
VDD
VSS
On/off
Output data register
Input data register
To on-chip peripherals
To ADC
Each ADC has 6 inputs optimized for high performance INP0 to INP5 and INN0 to INN5 (fast channels).Refer to
the ADC connectivity figure in the reference manual
STM32H723/733, STM32H725/735 and STM32H730
advanced Arm
®
-based 32-bit MCUs (RM0468).
The other 14 channels have lower performance (slow channels)
STM32CubeMX and the table “pin/ball definition” in the
STM32H72x and STM32H73x datasheet show the
availability of the Pxy_C and Pxy depending on the package.
4.1.1 Packages having Pxy_C and Pxy pads available
The Pxy_C pads are routed with a direct connection to the ADC fast input channels.
For these packages, use the Pxy_C inputs for the ADC to get the best performance (see the
STM32H72x and
STM32H73x datasheets ADC characteristic table “Sampling rate for Direct channels”)
The performance of the Pxy standard pads connected to the ADC fast channels are described in the STM32H72x
and STM32H73x datasheets ADC characteristic table “Sampling rate for Fast channels
The performance of the Pxy standard pads connected to the ADC slow channels are described in the
STM32H72x and STM32H73x datasheets ADC characteristic table “Sampling rate for Fast channels
AN5419
Alternate function mapping to pins
AN5419 - Rev 2
page 24/50