S-7750C Datasheet, PDF (28/44 Pages) Seiko Instruments Inc – PROGRAMMABLE PORT CONTROLLER (PORT EXPANDER WITH BUILT-IN E2PROM CIRCUIT)

PROGRAMMABLE PORT CONTROLLER (PORT EXPANDER WITH BUILT-IN E²PROM CIRCUIT)
S-7750C
Rev.1.1_00
4. 2 Initialization time
The S-7750C initializes at the same time when the power supply voltage is raised. Input instructions to the S-7750C
after initialization. The S-7750C does not accept any instruction during initialization.
Figure 34 shows the initialization time of the S-7750C.
(Condition : V_CCH = 3.0 V, Ta = 25°C)
100 m
10 m
S-7750C initialization
time (tINIT) Max.
1.0 m
[s]
100 µ
10 µ
1.0 µ
1.0 µ 10 µ 100 µ 1.0 m 10 m 100 m
Rise time (t_RISE)
[s]
Figure 34 Initialization Time
5. Data hold time (t_{HD. DAT} = 0 ns)
If SCL and SDA of the S-7750C are changed at the same time, the timing which takes to reach the S-7750C slightly
lags due to a load on the bus line. As a result, the change in the SDA precedes a falling edge of SCL so that
S-7750C may recognize a start/stop condition.
To avoid this, in the S-7750C, it is recommended to set the delay time of over 0.3 µs for a falling edge of SCL.
In its specs, it is described as the S-7750C works at 0 ns of data hold time, however, take account into the above
action in actual use.
t_{HD. DAT} = 0.3 µs Min.
SCL
SDA
Figure 35 Data Hold Time
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Seiko Instruments Inc.