27.18
Inter-Integrated Circuit (I
2
C) Interface
Table 27-48. I
2
C Characteristics
Unit
Max
Nom
Min
Parameter Name
Parameter
Parameter
No.
system clocks
-
-
36
Start condition hold time
T
SCH
I1
a
system clocks
-
-
36
Clock Low period
T
LP
I2
a
ns
(see note
b)
-
-
I2CSCL
/
I2CSDA
rise time (V
IL
=0.5 V
to V
IH
=2.4 V)
T
SRT
I3
b
system clocks
-
2
-
Data hold time (slave)
T
DH
I4
system clocks
-
7
-
Data hold time (master)
ns
10
9
-
I2CSCL
/
I2CSDA
fall time (V
IH
=2.4 V
to V
IL
=0.5 V)
T
SFT
I5
c
system clocks
-
-
24
Clock High time
T
HT
I6
a
system clocks
-
-
18
Data setup time
T
DS
I7
system clocks
-
-
36
Start condition setup time (for
repeated start condition only)
T
SCSR
I8
a
system clocks
-
-
24
Stop condition setup time
T
SCS
I9
a
system clocks
-
2
-
Data Valid (slave)
T
DV
I10
system clocks
-
(6 * (1 +
TPR)) + 1
-
Data Valid (master)
a. Values depend on the value programmed into the
TPR
bit in the
I
2
C Master Timer Period (I2CMTPR)
register; a
TPR
programmed for the maximum
I2CSCL
frequency (TPR=0x2) results in a minimum output timing as shown in the table
above. The I
2
C interface is designed to scale the actual data transition time to move it to the middle of the
I2CSCL
Low
period. The actual position is affected by the value programmed into the
TPR
; however, the numbers given in the above
values are minimum values.
b. Because
I2CSCL
and
I2CSDA
operate as open-drain-type signals, which the controller can only actively drive low, the
time
I2CSCL
or
I2CSDA
takes to reach a high level depends on external signal capacitance and pull-up resistor values.
c. Specified at a nominal 50 pF load.
Figure 27-33. I
2
C Timing
I2CSCL
I2CSDA
I1
I2
I6
I7
I8
I5
I3
I9
I4
I10
June 18, 2014
1870
Texas Instruments-Production Data
Electrical Characteristics