STM32F101X6_08 STMICROELECTRONICS [STMicroelectronics], STM32F101X6_08 Datasheet - Page 41

• Manufacturer Part Number: STM32F101X6_08
• Description: Access line, advanced ARM-based 32-bit MCU with Flash memory, six 16-bit timers, ADC and seven communication interfaces
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

STM32F101xx
Figure 18. Low-speed external clock source AC timing diagram
Table 21.
1. Resonator characteristics given by the crystal/ceramic resonator manufacturer.
2. For C
3. The relatively low value of the RF resistor offers a good protection against issues resulting from use in a humid
4. Based on characterization results, not tested in production.
5. t
Symbol
t
f
SU(HSE)
OSC_IN
C
g
high-frequency applications, and selected to match the requirements of the crystal or resonator. C
the same size. The crystal manufacturer typically specifies a load capacitance which is the series combination of C
C
the combined pin and board capacitance).
environment, due to the induced leakage and the bias condition change. However, it is recommended to take this point into
account if the MCU is used in tough humidity conditions.
reached. This value is measured for a standard crystal resonator and it can vary significantly with the crystal manufacturer
C
SU(HSE)
V LSEH
R
L2
m
(5)
V LSEL
i
L2
2
L1
F
(4)
(2)
. PCB and MCU pin capacitance must be included when sizing C
L1
and C
is the startup time measured from the moment it is enabled (by software) to a stabilized 8 MHz oscillation is
Oscillator frequency
Feedback resistor
Recommended load capacitance versus
equivalent serial resistance of the crystal (R
HSE driving current
Oscillator transconductance
Startup time
High-speed external clock
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
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).
HSE 4-16 MHz oscillator characteristics
90%
10%
L2
EXTER NAL
CLOCK SOURC E
it is recommended to use high-quality ceramic capacitors in the 5 pF to 25 pF range (typ.), designed for
t r(LSE)
Parameter
f LSE_ext
T LSE
OSC32_IN
t f(LSE)
S
)
(3)
(1)
R
V
V
load
Startup
V
DD
IN
S
DD
L1
= 30 Ω
= V
= 3.3 V
and C
Conditions
is stabilized
SS
L2
with 30 pF
t W(LSE)
(10 pF can be used as a rough estimate of
I L
STM32F101
Table
Min
Electrical characteristics
25
4
21. In the application,
L1
and C
Typ
200
30
8
2
L2,
t W(LSE)
are usually
Max
16
ai14140b
1
L1
and
mA/V
MHz
Unit
t
mA
ms
41/74
kΩ
pF