S-7750C

Seiko Instruments Inc.

4

General Description of Pin Function

1. SDA (Serial data I/O) pin

The SDA pin transmits serial data bi-directionally, is comprised of a signal input pin and a pin with Nch transistor open

drain output. In use, generally, connect the SDA line to any other device which has the open-drain or open-collector

2. SCL (Input for serial clock) pin

The SCL pin is an input pin for serial clock, processes a signal at a rising / falling edge of SCL clock. Pay attention

fully to the rising / falling time and comply with specifications.

3. WP (Input for Write protect) pin

This pin performs Write Protect to E

4. TIMEN (Input for timer enable) pin

This pin controls enable (“H”) /disable (“L”) / start (“L”→”H”) in the timer action (inversion of digital output due to

elapsed period). Regarding the timer action, refer to “

Command” and “

Condition to start timer, Port Output

≥ 2.5 V.

5. CLK (Input for external clock) pin

As primary clock in the circuit action, users are able to use clock either from the internal oscillation circuit or input it

externally by option. Users can input clock from this pin in case of using external clock. If not, connect this pin to

VCCH or GND.

6. DO7 to DO0 (Digital output) pin

These pins are for the digital output port. Their values are equal to the ones of a control port register during output. Its

output inverts after; the timer starts and delay time has elapsed. Regarding the timer action, refer to “ Command”

and “ Condition to start timer, Port Output and Register”.

7. VSS pin

Connect to GND.

8. VCCH pin

Except for the output ports, the power supply is applied to the entire circuit via this pin. Regarding the voltage’s value

to be applied to this pin, refer to “ Recommended Operating Conditions”.

9. VCCL pin

This pin is to apply the power supply for the output ports. Regarding the voltage’s value to be applied to this pin, refer

to “ Recommended Operating Conditions”.