Datasheet

Section 17 I
2
C Bus Interface (IIC)
Rev. 3.00 Sep. 28, 2009 Page 558 of 910
REJ09B0350-0300
Table 17.11 I
2
C Bus Timing (with Maximum Influence of t
Sr
/t
Sf
)
Time Indication (at Maximum Transfer Rate) [ns]
Item t
cyc
Indication
t
Sr
/t
Sf
Influence
(Max.)
I
2
C Bus
Specification
(Min.)
φ =
8 MHz
φ =
10 MHz
φ =
16 MHz
φ =
20 MHz
Standard mode –1000 4000 4000 4000 4000 4000 t
SCLHO
0.5 t
SCLO
(–t
Sr
)
High-speed mode –300 600 950 950 950 950
Standard mode –250 4700 4750 4750 4750 4750 t
SCLLO
0.5 t
SCLO
(–t
Sf
)
High-speed mode –250 1300 1000*
1
1000*
1
1000*
1
1000*
1
Standard mode –1000 4700 3875*
1
3900*
1
3939*
1
3950*
1
t
BUFO
0.5 t
SCLO
–1 t
cyc
(–t
Sr
)
High-speed mode –300 1300 825*
1
850*
1
888*
1
900*
1
Standard mode –250 4000 4625 4650 4688 4700 t
STAHO
0.5 t
SCLO
–1 t
cyc
(–t
Sf
)
High-speed mode –250 600 875 900 938 900
Standard mode –1000 4700 9000 9000 9000 9000 t
STASO
1 t
SCLO
(–t
Sr
)
High-speed mode –300 600 2200 2200 2200 2200
Standard mode –1000 4000 4250 4200 4125 4100 t
STOSO
0.5 t
SCLO
+ 2 t
cyc
(–t
Sr
)
High-speed mode –300 600 1200 1150 1075 1050
Standard mode –1000 250 3325 3400 3513 3550 t
SDASO
(master)
1 t
SCLLO
*
3
–3 t
cyc
(–t
Sr
)
High-speed mode –300 100 625 700 813 850
Standard mode –1000 250 2200 2500 2950 3100 t
SDASO
(slave)
1 t
SCLL
*
3
–12 t
cyc
*
2
(–t
Sr
)
High-speed mode –300 100 –500*
1
–200*
1
250 400
t
SDAHO
3 t
cyc
Standard mode 0 0 375 300 188 150
High-speed mode 0 0 375 300 188 150
Notes: 1. Does not meet the I
2
C bus interface specification. Remedial action such as the following
is necessary: (a) secure a start/stop condition issuance interval; (b) adjust the rise and
fall times by means of a pull-up resistor and capacitive load; (c) reduce the transfer rate;
(d) select slave devices whose input timing permits this output timing.
The values in the above table will vary depending on the settings of the IICX bit and bits
CKS0 to CKS2. Depending on the frequency it may not be possible to achieve the
maximum transfer rate; therefore, whether or not the I
2
C bus interface specifications are
met must be determined in accordance with the actual setting conditions.
2. Value when the IICX bit is set to 1. When the IICX bit is cleared to 0, the value is (t
SCLL
–
6 t
cyc
).
3. Calculated using the I
2
C bus specification values (standard mode: 4700 ns min.; high-
speed mode: 1300 ns min.).