S-35392A Datasheet, PDF (3/47 Pages) Seiko Instruments Inc – 2-WIRE REAL-TIME CLOCK

Rev.1.3_00
2-WIRE REAL-TIME CLOCK
S-35392A
„ Pin Function
• SDA (I/O for serial data) pin
This pin is to data input/output for I²C-bus interface. This pin inputs/outputs data by synchronizing with a clock pulse
from the SCL pin. This pin has CMOS input and Nch open drain output. Generally in use, pull up this pin to the VDD
potential via a resistor, and connect it to any other device having open drain or open collector output with wired-OR
connection.
• SCL (input for serial clock) pin
This pin is to input a clock pulse for I²C-bus interface. The SDA pin inputs/outputs data by synchronizing with the clock
pulse.
• 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.
• INT2 (output for interrupt signal 2) pin
This pin outputs a signal of interrupt, or a clock pulse. By using the status register 2, users can select either of; alarm
interrupt, output of user-set frequency, per-minute edge interrupt or minute-periodical interrupt 1. This pin has Nch open
drain output.
• 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
SDA
SCL
Figure 2 SDA Pin
32KO, INT2
Figure 3 SCL Pin
Figure 4 32KO Pin, INT2 Pin
Seiko Instruments Inc.
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