Electrical characteristics
STM32F103x8, STM32F103xB
Figure 21. High-speed external clock source AC timing diagram
VHSEH
90%
VHSEL
10%
tr(HSE)
THSE
tf(HSE)
tW(HSE)
tW(HSE)
t
EXTER NAL
CLOCK SOURC E
fHSE_ext
OSC _IN
IL
STM32F103xx
ai14143
Figure 22. Low-speed external clock source AC timing diagram
VLSEH
90%
VLSEL
10%
tr(LSE)
TLSE
tf(LSE)
tW(LSE)
tW(LSE)
t
EXTER NAL
CLOCK SOURC E
fLSE_ext
OSC32_IN
IL
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
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).
50/96
Doc ID 13587 Rev 12
STMICROELECTRONICS [ STMICROELECTRONICS ]
