STM32F051R6T6 Datasheet, PDF (61/104 Pages) STMicroelectronics – Low- and medium-density advanced ARM-based 32-bit MCU

Electrical characteristics
Figure 15. Typical application with a 32.768 kHz crystal
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Note:
6.3.7
-3
An external resistor is not required between OSC32_IN and OSC32_OUT and it is forbidden
to add one.
Internal clock source characteristics
The parameters given in Table 38 are derived from tests performed under ambient
temperature and supply voltage conditions summarized in Table 20.
High-speed internal (HSI) RC oscillator
Table 38. HSI oscillator characteristics⁽¹⁾
Symbol
Parameter
Conditions
f_HSI
TRIM
DuCy_(HSI)
ACC_HSI
t_su(HSI)
Frequency
HSI user trimming step
Duty cycle
Accuracy of the HSI
oscillator (factory
calibrated)
HSI oscillator startup
time
T_A = –40 to 105 °C
T_A = –10 to 85 °C
T_A = 0 to 70 °C
T_A = 25 °C
I_DD(HSI)
HSI oscillator power
consumption
1. V_DDA = 3.3 V, T_A = –40 to 105 °C unless otherwise specified.
2. Guaranteed by design, not tested in production.
3. Data based on characterization results, not tested in production.
Min Typ
-
8
-
-
45⁽²⁾
-
–3.8⁽³⁾
-
–2.9⁽³⁾
-
–1.3⁽³⁾
-
–1
-
1⁽²⁾
-
Max
1⁽²⁾
55⁽²⁾
4.6⁽³⁾
2.9⁽³⁾
2.2⁽³⁾
1
2⁽²⁾
Unit
MHz
%
%
%
%
%
%
µs
-
80 100⁽²⁾ µA
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Doc ID 022265 Rev 3