I Pin Assignment
1 8 VDD
2 7 SIO
3 6 SCK
4 5 CS
I Pin Function
Standard signal output (Nch open-drain output or CMOS output)
Connects to the X’ftal resonator (f=32,768 Hz)
Built-in Cg/Cd, or Cd only
Power supply (GND)
Chip select input (Built-in pull-down resistance) :
“H”: The SIO pin is capable of inputting/outputting data.
The SCK pin is capable of accepting the input.
“L”: The SIO pin is at Hi-Z.
The SCK pin is not capable of accepting the input.
Clock input :
Inputs and outputs data from the SIO pin in synchronization with the
clock. The clock cannot be accepted when the CS pin is “L”.
Serial data input/output :
When the CS is “L”, the SIO pin is at “Hi-Z”. When the CS pin changes
from “L” to “H”, it serves as the input pin. The SIO pin is assigned to the
input or output pin according to the next command data. The type of
output is either Nch open-drain or CMOS depending upon the model of
the IC you use.
Positive power supply
Seiko Instruments Inc.