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STM32L151xC/C-A STM32L152xC/C-A
Electrical characteristics
113
6.3.6 External
clock
source characteristics
High-speed external user clock generated from an external source
In bypass mode the HSE oscillator is switched off and the input pin is a standard GPIO.The
external clock signal has to respect the I/O characteristics in
. However, the
recommended clock input waveform is shown in
Table 25. Low-power mode wakeup timings
Symbol
Parameter
Conditions
Typ
Max
(1)
1. Guaranteed by characterization, not tested in production, unless otherwise specified
Unit
t
WUSLEEP
Wakeup from Sleep mode
f
HCLK
= 32 MHz
0.4
-
µs
t
WUSLEEP_LP
Wakeup from Low-power sleep
mode, f
HCLK
= 262 kHz
f
HCLK
= 262 kHz
Flash enabled
46
-
f
HCLK
= 262 kHz
Flash switched OFF
46
-
t
WUSTOP
Wakeup from Stop mode,
regulator in Run mode
ULP bit = 1 and FWU bit = 1
f
HCLK
= f
MSI
= 4.2 MHz
8.2
-
Wakeup from Stop mode,
regulator in low-power mode
ULP bit = 1 and FWU bit = 1
f
HCLK
= f
MSI
= 4.2 MHz
Voltage range 1 and 2
7.7
8.9
f
HCLK
= f
MSI
= 4.2 MHz
Voltage range 3
8.2
13.1
f
HCLK
= f
MSI
= 2.1 MHz
10.2
13.4
f
HCLK
= f
MSI
= 1.05 MHz
16
20
f
HCLK
= f
MSI
= 524 kHz
31
37
f
HCLK
= f
MSI
= 262 kHz
57
66
f
HCLK
= f
MSI
= 131 kHz
112
123
f
HCLK
= MSI = 65 kHz
221
236
t
WUSTDBY
Wakeup from Standby mode
ULP bit = 1 and FWU bit = 1
f
HCLK
= MSI = 2.1 MHz
58
104
Wakeup from Standby mode
FWU bit = 0
f
HCLK
= MSI = 2.1 MHz
2.6
3.25
ms
Table 26. High-speed external user clock characteristics
(1)
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
f
HSE_ext
User external clock source
frequency
CSS is on or
PLL is used
1
8
32
MHz
CSS is off, PLL
not used
0
8
32
MHz