Datasheet

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STM32L151x6/8/B, STM32L152x6/8/B Electrical characteristics
105
Figure 19. I/O AC characteristics definition
6.3.14 NRST pin characteristics
The NRST pin input driver uses CMOS technology. It is connected to a permanent pull-up
resistor, RPU (see Table 45).
Unless otherwise specified, the parameters given in Table 45 are derived from tests
performed under ambient temperature and V
DD
supply voltage conditions summarized in
Table 13.
11
F
max(IO)out
Maximum frequency
(3)
C
L
= 50 pF, V
DD
= 2.7
V to 3.6 V
-50
MHz
C
L
= 50 pF, V
DD
=
1.65 V to 2.7 V
-8
t
f(IO)out
t
r(IO)out
Output rise and fall time
C
L
= 30 pF, V
DD
= 2.7
V to 3.6 V
-5
ns
C
L
= 50 pF, V
DD
=
1.65 V to 2.7 V
-30
-t
EXTIpw
Pulse width of external
signals detected by the
EXTI controller
-8-
1. The I/O speed is configured using the OSPEEDRx[1:0] bits. Refer to the STM32L15xxx 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 19.
Table 44. I/O AC characteristics
(1)
(continued)
OSPEEDRx
[1:0] bit
value
(1)
Symbol Parameter Conditions Min Max
(2)
Unit
ai14131b
10%
90%
50%
t
r( I O)out
External
Output
on 50pF
Maximum frequency is achieved if (t
r
+ t
f
) ≤ 2/3)T and if the duty cycle is (45-55%)
10 %
50%
90%
when loaded by 50 pF
T
t
f(I O)out