Electrical characteristics
STM32F091xB STM32F091xC
Output driving current
The GPIOs (general purpose input/outputs) can sink or source up to +/-8 mA, and sink or
source up to +/- 20 mA (with a relaxed VOL/VOH).
In the user application, the number of I/O pins which can drive current must be limited to
respect the absolute maximum rating specified in Section 6.2:
• The sum of the currents sourced by all the I/Os on VDDIOx, plus the maximum
consumption of the MCU sourced on VDD, cannot exceed the absolute maximum rating
ΣIVDD (see Table 21: Voltage characteristics).
• The sum of the currents sunk by all the I/Os on VSS, plus the maximum consumption of
the MCU sunk on VSS, cannot exceed the absolute maximum rating ΣIVSS (see
Table 21: Voltage characteristics).
Output voltage levels
Unless otherwise specified, the parameters given in the table below are derived from tests
performed under the ambient temperature and supply voltage conditions summarized in
Table 24: General operating conditions. All I/Os are CMOS- and TTL-compliant (FT, TTa or
TC unless otherwise specified).
Table 54. Output voltage characteristics(1)
Symbol
Parameter
Conditions
Min
Max Unit
VOL
VOH
VOL
VOH
VOL(3)
VOH(3)
VOL(3)
VOH(3)
VOL(4)
VOH(4)
Output low level voltage for an I/O pin
Output high level voltage for an I/O pin
Output low level voltage for an I/O pin
Output high level voltage for an I/O pin
Output low level voltage for an I/O pin
Output high level voltage for an I/O pin
Output low level voltage for an I/O pin
Output high level voltage for an I/O pin
Output low level voltage for an I/O pin
Output high level voltage for an I/O pin
VOLFm+(3)
Output low level voltage for an FTf I/O pin in
Fm+ mode
CMOS port(2)
|IIO| = 8 mA
VDDIOx ≥ 2.7 V
TTL port(2)
|IIO| = 8 mA
VDDIOx ≥ 2.7 V
|IIO| = 20 mA
VDDIOx ≥ 2.7 V
|IIO| = 6 mA
VDDIOx ≥ 2 V
|IIO| = 4 mA
|IIO| = 20 mA
VDDIOx ≥ 2.7 V
|IIO| = 10 mA
-
0.4
V
VDDIOx–0.4
-
-
0.4
V
2.4
-
-
1.3
V
VDDIOx–1.3
-
-
0.4
V
VDDIOx–0.4
-
-
0.4 V
VDDIOx–0.4
-
V
-
0.4 V
-
0.4 V
1.
The IIO
Voltage
respect
current sourced or sunk by the
characteristics, and the sum of
the absolute maximum ratings
device must
ΣthIeIOc.urrents
always respect the
sourced or sunk by
absolute maximum rating
all the I/Os (I/O ports and
specified in Table
control pins) must
21:
always
2. TTL and CMOS outputs are compatible with JEDEC standards JESD36 and JESD52.
3. Data based on characterization results. Not tested in production.
4. Data based on characterization results. Not tested in production.
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