PIC17C75X
2
FIGURE E-12: I C BUS DATA TIMING SPECIFICATION
103
102
100
101
SCL
90
106
107
91
92
SDA
In
110
109
109
SDA
Out
2
TABLE E-3:
I C BUS DATA TIMING SPECIFICATION
Microchip
Parameter
No.
Sym
Characteristic
Min
Max
Units
Conditions
100
101
102
THIGH
Clock high time
Clock low time
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
4.0
0.6
—
—
µs
µs
µs
µs
ns
ns
TLOW
TR
4.7
—
1.3
—
SDA and SCL rise
time
—
1000
300
20 + 0.1Cb
Cb is specified to be from
10 to 400 pF
103
TF
SDA and SCL fall time 100 kHz mode
400 kHz mode
—
300
300
ns
ns
20 + 0.1Cb
Cb is specified to be from
10 to 400 pF
90
91
TSU:STA START condition
setup time
100 kHz mode
400 kHz mode
4.7
0.6
4.0
0.6
0
—
—
µs
µs
µs
µs
ns
µs
ns
ns
µs
µs
ns
ns
µs
µs
Only relevant for repeated
START condition
THD:STA START condition hold 100 kHz mode
—
After this period the first clock
pulse is generated
time
400 kHz mode
100 kHz mode
400 kHz mode
—
106
107
92
THD:DAT Data input hold time
—
0
0.9
—
TSU:DAT Data input setup time 100 kHz mode
400 kHz mode
250
100
4.7
0.6
—
Note 2
—
TSU:STO STOP condition setup 100 kHz mode
—
time
400 kHz mode
100 kHz mode
400 kHz mode
100 kHz mode
400 kHz mode
—
109
110
TAA
Output valid from
clock
3500
1000
—
Note 1
—
TBUF
Bus free time
4.7
1.3
Time the bus must be free
before a new transmission
can start
—
D102
Cb
Bus capacitive loading
—
400
pF
Note 1: As a transmitter, the device must provide this internal minimum delay time to bridge the undefined region (min. 300 ns) of
the falling edge of SCL to avoid unintended generation of START or STOP conditions.
2
2
2: A fast-mode I C-bus device can be used in a standard-mode I C-bus system, but the requirement tsu;DAT ≥ 250 ns must
then be met. This will automatically be the case if the device does not stretch the LOW period of the SCL signal. If such a
device does stretch the LOW period of the SCL signal, it must output the next data bit to the SDA line
2
TR max.+tsu;DAT = 1000 + 250 = 1250 ns (according to the standard-mode I C bus specification) before the SCL line is
released.
DS30264A-page 272
Preliminary
1997 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
