Electrical characteristics
STM32F103x8, STM32F103xB
Figure 22. High-speed external clock source AC timing diagram
V
HSEH
90%
10%
V
HSEL
t
t
t
W(HSE)
t
t
W(HSE)
r(HSE)
f(HSE)
T
HSE
f
HSE_ext
EXTERNAL
CLOCK SOURCE
I
L
OSC _IN
STM32F103xx
ai14143
Figure 23. Low-speed external clock source AC timing diagram
V
LSEH
90%
10%
V
LSEL
t
t
t
W(LSE)
t
t
W(LSE)
r(LSE)
f(LSE)
T
LSE
f
LSE_ext
EXTERNAL
CLOCK SOURCE
I
L
OSC32_IN
STM32F103xx
ai14144b
High-speed external clock generated from a crystal/ceramic resonator
The high-speed external (HSE) clock can be supplied with a 4 to 16 MHz crystal/ceramic
resonator oscillator. All the information given in this paragraph are based on characterization
results obtained with typical external components specified in Table 22. 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 startup stabilization time. Refer to the crystal
resonator manufacturer for more details on the resonator characteristics (frequency,
package, accuracy).
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Doc ID 13587 Rev 15
STMICROELECTRONICS [ ST ]
