Electrical characteristics
STM32F100x4, STM32F100x6, STM32F100x8, STM32F100xB
2
(1)
Figure 27. I C bus AC waveforms and measurement circuit
6
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1. Measurement points are done at CMOS levels: 0.3VDD and 0.7VDD
.
(1)(2)
Table 39. SCL frequency (f
fSCL (kHz)
= 24 MHz, VDD = 3.3 V)
PCLK1
I2C_CCR value
RP = 4.7 k
400
300
200
100
50
0x8011
0x8016
0x8021
0x0064
0x00C8
0x01F4
20
1. RP = External pull-up resistance, fSCL = I2C speed,
2. For speeds around 400 kHz, the tolerance on the achieved speed is of 2%. For other speed ranges, the
tolerance on the achieved speed 1%. These variations depend on the accuracy of the external
components used to design the application.
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Doc ID 16455 Rev 2
STMICROELECTRONICS [ ST ]
