S-35740C01A-K8T2U Datasheet, PDF (20/31 Pages) Seiko Instruments Inc – Operation temperature range

FOR AUTOMOTIVE 125°C OPERATION 2-WIRE INTERVAL TIMER CONVENIENCE TIMER
S-35740 Series
Rev.1.1_00
 Release of SDA
The ENBL pin of the S-35740 Series does not perform the reset operation of the communication interface. Therefore,
the stop condition is input to reset the internal interface circuit usually.
However, the S-35740 Series does not accept the stop condition from the master device when in the status that SDA
outputs "L" (at the time of acknowledge outputting or reading). Consequently, it is necessary to finish the acknowledge
output or read operation. Figure 26 shows the SDA release method.
First, input the start condition from the master device (since SDA of the S-35740 Series outputs "L", the S-35740
Series can not detect the start condition). Next, input the clocks for 1-byte data access (9 clocks) from SCL. During the
time, release SDA of the master device. By this, the SDA input / output before communication interrupt is completed,
and SDA of the S-35740 Series becomes release status. Continuously, if the stop condition is input, the internal circuit
resets and the communication returns to normal status.
It is strongly recommended that the SDA release method is performed at the time of system initialization after the
power supply voltage of the master device rises.
Start condition
SCL
Clocks for 1-byte data access
Stop condition
12
8
9
SDA
(Master device output)
SDA
(S-35740 output)
"L"
"L"
SDA
"L" or High-Z
"L" or High-Z
High-Z
Figure 26 SDA Release Method
20