STMicroelectronics STM32F042C6, Руководство пользователя

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STM32F042x4 STM32F042x6 Electrical characteristics
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Figure 24. I/O AC characteristics definition
6.3.15 NRST pin characteristics
The NRST pin input driver uses the CMOS technology. It is connected to a permanent pull-
up resistor, R
PU
.
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 21: General operating conditions
.
Fm+
configuration
(4)
f
max(IO)out
Maximum frequency
(3)
C
L
= 50 pF, V
DDIOx
≥ 2 V
- 2 MHz
t
f(IO)out
Output fall time - 12
ns
t
r(IO)out
Output rise time - 34
f
max(IO)out
Maximum frequency
(3)
C
L
= 50 pF, V
DDIOx
< 2 V
- 0.5 MHz
t
f(IO)out
Output fall time - 16
ns
t
r(IO)out
Output rise time - 44
- t
EXTIpw
Pulse width of external
signals detected by the
EXTI controller
- 10 - ns
1. The I/O speed is configured using the OSPEEDRx[1:0] bits. Refer to the STM32F0xxxx RM0091 reference manual for a
description of GPIO Port configuration register.
2. Guaranteed by design, not tested in production.
3. The maximum frequency is defined in
Figure 24
.
4. When Fm+ configuration is set, the I/O speed control is bypassed. Refer to the STM32F0xxxx reference manual RM0091
for a detailed description of Fm+ I/O configuration.
Table 52. I/O AC characteristics
(1)(2)
(continued)
OSPEEDRy
[1:0] value
(1)
Symbol Parameter Conditions Min Max Unit
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Table 53. NRST pin characteristics
Symbol Parameter Conditions Min Typ Max Unit
V
IL(NRST)
NRST input low level voltage - - - 0.3 V
DD
+0.07
(1)
V
V
IH(NRST)
NRST input high level voltage - 0.445 V
DD
+0.398
(1)
- -