STM32F301x6 STM32F301x8
Electrical characteristics
6.3.17
Communications interfaces
I2C interface characteristics
The I2C interface meets the timings requirements of the I2C-bus specification and user
manual rev. 03 for:
• Standard-mode (Sm): with a bit rate up to 100 kbit/s
• Fast-mode (Fm): with a bit rate up to 400 kbit/s
• Fast-mode Plus (Fm+): with a bit rate up to 1 Mbit/s.
The I2C timings requirements are guaranteed by design when the I2C peripheral is properly
configured (refer to Reference manual).
The SDA and SCL I/O requirements are met with the following restrictions: the SDA and
SCL I/O pins are not "true" open-drain. When configured as open-drain, the PMOS
connected between the I/O pin and VDDIOx is disabled, but is still present. Only FTf I/O pins
support Fm+ low level output current maximum requirement. Refer to Section 6.3.14: I/O
port characteristics for the I2C I/Os characteristics.
All I2C SDA and SCL I/Os embed an analog filter. Refer to the table below for the analog
filter characteristics:
Table 61. I2C analog filter characteristics(1)
Symbol
Parameter
Min
Max
tAF
Maximum pulse width of spikes that
are suppressed by the analog filter
50(2)
260(3)
1. Guaranteed by design.
2. Spikes with widths below tAF(min) are filtered.
3. Spikes with widths above tAF(max) are not filtered
Unit
ns
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