CD00237391 Datasheet, PDF (81/177 Pages) STMicroelectronics – ARM-based 32-bit MCU, 150DMIPs, up to 1 MB Flash/128+4KB RAM

STM32F20xxx
Electrical characteristics
5.3.8
External clock source characteristics
High-speed external user clock generated from an external source
The characteristics given in Table 26 result from tests performed using an high-speed
external clock source, and under ambient temperature and supply voltage conditions
summarized in Table 12.
Table 26. High-speed external user clock characteristics
Symbol
Parameter
Conditions Min Typ Max Unit
f_{HSE_ext}
External user clock source
frequency⁽¹⁾
1
-
26 MHz
V_HSEH
V_HSEL
OSC_IN input pin high level voltage
OSC_IN input pin low level voltage
0.7V_DD -
V_DD
V
V_SS
- 0.3V_DD
t_w(HSE)
t_w(HSE)
t_r(HSE)
t_f(HSE)
C_in(HSE)
OSC_IN high or low time⁽¹⁾
OSC_IN rise or fall time⁽¹⁾
OSC_IN input capacitance⁽¹⁾
5
-
-
ns
-
-
20
-
5
-
pF
DuCy_(HSE) Duty cycle
45
-
55
%
I_L
OSC_IN Input leakage current
V_SS ≤ V_IN ≤ V_DD
-
-
±1 µA
1. Guaranteed by design, not tested in production.
Low-speed external user clock generated from an external source
The characteristics given in Table 27 result from tests performed using an low-speed
external clock source, and under ambient temperature and supply voltage conditions
summarized in Table 12.
Table 27. Low-speed external user clock characteristics
Symbol
Parameter
Conditions
Min Typ Max Unit
f_{LSE_ext}
User External clock source
frequency⁽¹⁾
-
32.768 1000 kHz
V_LSEH
V_LSEL
OSC32_IN input pin high level
voltage
OSC32_IN input pin low level
voltage
0.7V_DD
-
V_DD
V
V_SS
-
0.3V_DD
t_w(LSE)
t_f(LSE)
t_r(LSE)
t_f(LSE)
C_in(LSE)
OSC32_IN high or low time⁽¹⁾
OSC32_IN rise or fall time⁽¹⁾
OSC32_IN input capacitance⁽¹⁾
450
-
-
ns
-
-
50
-
5
-
pF
DuCy_(LSE) Duty cycle
30
-
70
%
I_L
OSC32_IN Input leakage current V_SS ≤ V_IN ≤ V_DD
-
-
±1
µA
1. Guaranteed by design, not tested in production.
Doc ID 15818 Rev 9
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