STM32F103xx
Electrical characteristics
5.3.6
External clock source characteristics
High-speed external user clock
The characteristics given in Table 15 result from tests performed using an high-speed
external clock source, and under ambient temperature and supply voltage conditions
summarized in Table 7.
Table 15. High-speed external (HSE) user clock characteristics
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
User external clock source
frequency(1)
fHSE_ext
8
25
MHz
OSC_IN input pin high level
voltage
VHSEH
VHSEL
0.7VDD
VSS
VDD
V
OSC_IN input pin low level
voltage
0.3VDD
tw(HSE)
tw(HSE)
OSC_IN high or low time(1)
OSC_IN rise or fall time(1)
16
ns
tr(HSE)
tf(HSE)
5
OSC_IN Input leakage
current
IL
VSS ≤VIN ≤VDD
±1
µA
1. Value based on design simulation and/or technology characteristics. It is not tested in production.
Low-speed external user clock
The characteristics given in Table 16 result from tests performed using an low-speed
external clock source, and under ambient temperature and supply voltage conditions
summarized in Table 7.
Table 16. Low-speed external user clock characteristics
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
User External clock source
frequency(1)
fLSE_ext
32.768
1000
kHz
OSC32_IN input pin high level
voltage
VLSEH
VLSEL
tw(LSE)
0.7VDD
VSS
VDD
V
OSC32_IN input pin low level
voltage
0.3VDD
OSC32_IN high or low time(1)
OSC32_IN rise or fall time(1)
450
tw(LSE)
ns
tr(LSE)
tf(LSE)
5
OSC32_IN Input leakage
current
IL
VSS ≤VIN ≤VDD
±1
µA
1. Value based on design simulation and/or technology characteristics. It is not tested in production.
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STMICROELECTRONICS [ ST ]
