Datasheet

STM32F051x Electrical characteristics
Doc ID 022265 Rev 3 63/105
High-speed internal 14 MHz (HSI14) RC oscillator (dedicated to ADC)
Low-speed internal (LSI) RC oscillator
Wakeup time from low-power mode
The wakeup times given in Table 41 is measured on a wakeup phase with a 8-MHz HSI RC
oscillator. The event used to wake up the device depends from the current operating mode:
● Stop or sleep mode: the wakeup event is WFE
● The wakeup pin used in stop and sleep mode is PA0 and in standby mode is the PA1.
All timings are derived from tests performed under ambient temperature and V
DD
supply
voltage conditions summarized in Ta bl e 2 0.
Table 39. HSI14 oscillator characteristics
(1)
1. V
DDA
= 3.3 V, T
A
= –40 to 105 °C unless otherwise specified.
Symbol Parameter Conditions Min Typ Max Unit
f
HSI14
Frequency - 14 MHz
TRIM HSI14 user-trimming step - - 1
(2)
2. Guaranteed by design, not tested in production.
%
DuCy
(HSI14)
Duty cycle 45
(2)
-55
(2)
%
ACC
HSI14
Accuracy of the HSI14
oscillator (factory calibrated)
T
A
= –40 to 105 °C –4.2
(3)
3. Data based on characterization results, not tested in production.
-5.1
(3)
%
T
A
= –10 to 85 °C –3.2
(3)
-3.1
(3)
%
T
A
= 0 to 70 °C –1.3
(3)
-2.2
(3)
%
T
A
= 25 °C –1 - 1 %
t
su(HSI14)
HSI14 oscillator startup time 1
(2)
-2
(2)
µs
I
DD(HSI14)
HSI14 oscillator power
consumption
-100150
(2)
µA
Table 40. LSI oscillator characteristics
(1)
1.
V
DDA
= 3.3 V, T
A
= –40 to 105 °C unless otherwise specified.
Symbol Parameter Min Typ Max Unit
f
LSI
Frequency 30 40 50 kHz
t
su(LSI)
(2)
2. Guaranteed by design, not tested in production.
LSI oscillator startup time - - 85 µs
I
DD(LSI)
(2)
LSI oscillator power consumption - 0.75 1.2 µA