STM32F378XX Datasheet, PDF (88/131 Pages) STMicroelectronics – Reset and power management

Electrical characteristics
Figure 21. Recommended NRST pin protection
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STM32F378xx
069
1. The reset network protects the device against parasitic resets.
2.
The user must ensure that the
Table 53. Otherwise the reset
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max
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specified
in
NPOR pin characteristics
The NPOR pin input driver uses CMOS technology. It is connected to a permanent pull-up
resistor to the V_DDA, R_PU (see Table 50).
Unless otherwise specified, the parameters given in Table 54 are derived from tests
performed under ambient temperature and V_DDA supply voltage conditions summarized in
Table 22.
Symbol
Table 54. NPOR pin characteristics
Parameter
Conditions Min Typ
Max Unit
V_IL(NPOR)(1) NPOR Input low level voltage
V_IH(NPOR)(1) NPOR Input high level voltage
-
-
-
0.475V_DDA
- 0.2
V
-
0.5V_DDA
+ 0.2
-
-
V_hys(NPOR)(1)
NPOR Schmitt trigger voltage
hysteresis
-
-
100
-
mV
R_PU
Weak pull-up equivalent resistor⁽²⁾ V_IN = V_SS
25
40
55
kΩ
1. Guaranteed by design.
2. The pull-up is designed with a true resistance in series with a switchable PMOS. This PMOS contribution to
the series resistance is minimal (~10% order).
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