Gpio Equivalent Schematics; Figure 1. Three-Volt Compliant Gpio Structure (Tc) - ST STM32 Application Note

AN4899
4.2

GPIO equivalent schematics

STM32 products integrate three main GPIO basic structures:
•
Three-volt compliant (abbreviated as TC).
The equivalent GPIO diagram structure is given in
•
Three-volt tolerant (abbreviated as TT).
•
Five-volt tolerant (abbreviated as FT)
The equivalent GPIO diagram structure for TT or FT is given in
Note: In Figure 1
depends on the STM32 product considered. The analog switch is controlled by enabling
analog peripheral on the given pin (not by setting the GPIO in the analog mode). Refer to
the product datasheet for details.
In Figure 1
STM32 product considered. Refer to the product datasheet for details.
Analog
Parasitic diode
and resistor
Analog IP
Alternate function input
Input data
register
Output data
register
Alternate function output
Digital
Note: The parasitic diode in the analog domain is connected to V
protection diode.
The voltage level called V
ESD protection block.
and Figure 2, the analog switch in the dotted square is optional. Its presence
and Figure 2, the V
DD

Figure 1. Three-volt compliant GPIO structure (TC)

V
DDA
Input buffer
Output
control
Ouput buffer
DD_FT
supply may refer to V
Analog
option
Analog switch
V
on/off
on/off
V
DD
PMOS
NMOS
V
V
SS
in some datasheets and reference manuals is inside the
AN4899 Rev 3
GPIO functional description
Figure 1.
Figure
or V according to the
DD DDIO2
V
DD DD
R
PU
R
PD
ESD
protection
V V
SS SS SS
and cannot be used as a
DDA
2.
I/O pin
MSv46872V1
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