STMicroelectronics STM32F042C4, Руководство пользователя

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Electrical characteristics STM32F042xx
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Low-speed internal (LSI) RC oscillator
6.3.9 PLL characteristics
The parameters given in Table 42 are derived from tests performed under ambient
temperature and supply voltage conditions summarized in Table 21: General operating
conditions .
Table 41. 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 μ s
I
DDA(LSI)
(2)
LSI oscillator power consumption - 0.75 1.2 μ A
Table 42. PLL characteristics
Symbol Parameter
Value
Unit
Min Typ Max
f
PLL_IN
PLL input clock
(1)
1. Take care to use the appropriate multiplier factors to obtain PLL input clock values compatible with the
range defined by f
PLL_OUT
.
1
(2)
8.0 24
(2)
MHz
PLL input clock duty cycle 40
(2)
- 60
(2)
%
f
PLL_OUT
PLL multiplier output clock 16
(2)
- 48 MHz
t
LOCK
PLL lock time - - 200
(2)
2. Guaranteed by design, not tested in production.
μ s
Jitter
PLL
Cycle-to-cycle jitter - - 300
(2)
ps