Datasheet

Electrical characteristics STM32F103x4, STM32F103x6
62/99 DocID15060 Rev 7
Figure 27. I/O AC characteristics definition
5.3.14 NRST pin characteristics
The NRST pin input driver uses CMOS technology. It is connected to a permanent pull-up
resistor, R
PU
(see Table 35).
Unless otherwise specified, the parameters given in Table 38 are derived from tests
performed under the ambient temperature and V
DD
supply voltage conditions summarized
in
Table 9.



T
R)/OUT
/54054
%84%2.!,
/.P&
-AXIMUMFREQUENCYISACHIEVEDIFT
R
T
F
4ANDIFTHEDUTYCYCLEIS



WHENLOADEDBYP&
4
T
F)/OUT
Table 38. NRST pin characteristics
Symbol Parameter Conditions Min Typ Max Unit
V
IL(NRST)
(1)
1. Guaranteed by design, not tested in production.
NRST Input low level voltage - –0.5 - 0.8
V
V
IH(NRST)
(1)
NRST Input high level voltage -2-V
DD
+0.5
V
hys(NRST)
NRST Schmitt trigger voltage
hysteresis
--200-mV
R
PU
Weak pull-up equivalent resistor
(2)
2. The pull-up is designed with a true resistance in series with a switchable PMOS. This PMOS contribution
to the series resistance must be minimum (~10% order).
V
IN
= V
SS
30 40 50 kΩ
V
F(NRST)
(1)
NRST Input filtered pulse ---100ns
V
NF(NRST)
(1)
NRST Input not filtered pulse -300--ns