S-35192A Datasheet, PDF (3/41 Pages) Seiko Instruments Inc – 3-WIRE REAL-TIME CLOCK

Rev.1.2_00
3-WIRE REAL-TIME CLOCK
S-35192A
„ Pin Function
• CS (input for chip select) pin
This pin is to input chip select, has a pull-down resistor. Communication is available when this pin is in “H” level. If not
using communication, set this pin “L” or open.
• SCK (input for serial clock) pin
This pin is to input a clock pulse for serial interface. When the CS pin is in “H”, the SIO pin inputs/outputs data by
synchronizing with the clock pulse. When the CS pin is in “L” or open, the SCK pin does not accept inputting a clock
pulse.
• SIO (I/O for serial data) pin
This pin is to data input/output for serial interface. When the CS pin is in “H”, the SIO pin inputs/outputs data by
synchronizing with a clock pulse from the SCK pin. The status is in high impedance when the CS pin is in “L” or open,
so that the S-35192A does not transmit data. Setting the CS pin to “H” level from “L” or open, this SIO pin goes in the
input status so that it receives the command data. This pin has CMOS input and Nch open drain output.
• XIN, XOUT (crystal oscillator connect) pin
Connect a crystal oscillator between XIN and XOUT.
• 32KO (constant output of 32.768 kHz) pin
This is an output pin for 32.768 kHz. This pin constantly outputs a clock pulse after power-on.
• VDD (positive power supply) pin
Connect this VDD pin with a positive power supply. Regarding the values of voltage to be applied, refer to “„
Recommended Operation Conditions”.
• VSS pin
Connect this VSS pin to GND.
„ Equivalent Circuits of I/O Pin
SCK
SIO
Figure 2 SCK pin
CS
Figure 3 SIO pin
32KO
Figure 4 CS pin
Figure 5 32KO pin
Seiko Instruments Inc.
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