STM8S207xx, STM8S208xx
Electrical characteristics
10.3.3
External clock sources and timing characteristics
HSE user external clock
Subject to general operating conditions for V and T .
DD
A
Table 31. HSE user external clock characteristics
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
User external clock source
frequency
fHSE_ext
0
24
MHz
OSCIN input pin high level
voltage
(1)
VHSEH
0.7 x VDD
VSS
VDD + 0.3 V
0.3 x VDD
1
V
OSCIN input pin low level
voltage
(1)
VHSEL
OSCIN input leakage
current
ILEAK_HSE
VSS < VIN < VDD
-1
µA
1. Data based on characterization results, not tested in production.
Figure 16. HSE external clock source
V
V
HSEH
HSEL
f
HSE
External clock
source
OSCIN
STM8
HSE crystal/ceramic resonator oscillator
The HSE clock can be supplied with a 1 to 24 MHz crystal/ceramic resonator oscillator. All
the information given in this paragraph is based on characterization results with specified
typical external components. In the application, the resonator and the load capacitors have
to be placed as close as possible to the oscillator pins in order to minimize output distortion
and start-up stabilization time. Refer to the crystal resonator manufacturer for more details
(frequency, package, accuracy...).
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