Datasheet

Electrical characteristics STM32F105xx, STM32F107xx
50/104 Doc ID 15274 Rev 6
5.3.7 Internal clock source characteristics
The parameters given in Ta bl e 24 are derived from tests performed under ambient
temperature and V
DD
supply voltage conditions summarized in Tabl e 9.
High-speed internal (HSI) RC oscillator
Low-speed internal (LSI) RC oscillator
Wakeup time from low-power mode
The wakeup times given in Tabl e 2 6 is measured on a wakeup phase with a 8-MHz HSI RC
oscillator. The clock source used to wake up the device depends from the current operating
mode:
● Stop or Standby mode: the clock source is the RC oscillator
● Sleep mode: the clock source is the clock that was set before entering Sleep mode.
Table 24. HSI oscillator characteristics
(1)
1. V
DD
= 3.3 V, T
A
= –40 to 105 °C unless otherwise specified.
Symbol Parameter Conditions Min Typ Max Unit
f
HSI
Frequency 8 MHz
DuCy
(HSI)
Duty cycle 45 55 %
ACC
HSI
Accuracy of the HSI
oscillator
User-trimmed with the RCC_CR
register
(2)
2. Refer to application note AN2868 “STM32F10xxx internal RC oscillator (HSI) calibration” available from the
ST website www.st.com.
1
(3)
3. Guaranteed by design, not tested in production.
%
Factory-
calibrated
(4)
4. Based on characterization, not tested in production.
T
A
= –40 to 105 °C –2 2.5 %
T
A
= –10 to 85 °C –1.5 2.2 %
T
A
= 0 to 70 °C –1.3 2 %
T
A
= 25 °C –1.1 1.8 %
t
su(HSI)
(4)
HSI oscillator
startup time
12µs
I
DD(HSI)
(4)
HSI oscillator
power consumption
80 100 µA
Table 25. LSI oscillator characteristics
(1)
1. V
DD
= 3 V, T
A
= –40 to 105 °C unless otherwise specified.
Symbol Parameter Min Typ Max Unit
f
LSI
(2)
2. Based on characterization, not tested in production.
Frequency 30 40 60 kHz
t
su(LSI)
(3)
3. Guaranteed by design, not tested in production.
LSI oscillator startup time 85 µs
I
DD(LSI)
(3)
LSI oscillator power consumption 0.65 1.2 µA