Communication Interfaces; Table 47. I 2 C Characteristics - STMicroelectronics STM32L151CB Manual

Electrical characteristics
6.3.16

Communication interfaces

2
I C interface characteristics
The STM32L15xx6/8/B product line I
2
I C communication protocol with the following restrictions: SDA and SCL are not "true"
open-drain I/O pins. When configured as open-drain, the PMOS connected between the I/O
pin and V
2
The I C characteristics are described in
injection characteristics
(SDA and SCL) .
Symbol
t
w(SCLL)
t
w(SCLH)
t
su(SDA)
t
h(SDA)
t
r(SDA)
t
r(SCL)
t
f(SDA)
t
f(SCL)
t
h(STA)
t
su(STA)
t
su(STO)
t
w(STO:STA)
C
b
1. Guaranteed by design, not tested in production.
2. f must be at least 2 MHz to achieve standard mode I
PCLK1
achieve fast mode I²C frequencies. It must be a multiple of 10 MHz to reach the 400 kHz maximum I²C fast
mode clock.
3. The maximum Data hold time has only to be met if the interface does not stretch the low period of SCL
signal.
86/129
is disabled, but is still present.
DD
for more details on the input/output alternate function characteristics
Table 47. I
Parameter
SCL clock low time
SCL clock high time
SDA setup time
SDA data hold time
SDA and SCL rise time
SDA and SCL fall time
Start condition hold time
Repeated Start condition
setup time
Stop condition setup time
Stop to Start condition time
(bus free)
Capacitive load for each bus
line
DocID17659 Rev 10
STM32L151x6/8/B, STM32L152x6/8/B
2
C interface meets the requirements of the standard
Table 47. Refer also to
2
C characteristics
2 (1)
Standard mode I C
Min Max
4.7 -
4.0 -
250 -
0 -
- 1000
- 300
4.0 -
4.7 -
4.0 -
4.7 -
- 400
C frequencies. It must be at least 4 MHz to
²
Section 6.3.12: I/O current
2 (1)(2)
Fast mode I C
Min Max
1.3 -
0.6 -
100 -
(3)
0 900
20 + 0.1C 300
b
- 300
0.6 -
0.6 -
0.6 -
1.3 -
- 400
Unit
µs
ns
µs
μs
μs
pF