S24CS0 datasheet(20/47 Pages) SII

20 / 47 page

2-WIRE CMOS SERIAL E2PROM

S-24CS01A/02A/04A/08A

Rev.4.4_00

Seiko Instruments Inc.

Using S-24CS01A/02A/04A/08A

1. Adding a pull-up resistor to SDA I/O pin and SCL input pin

Add a 1 to 5 k

Ω pull-up resistor to the SCL input pin

*1 and the SDA I/O pin in order to enable the functions

of the I

2C-bus protocol. Normal communication cannot be provided without a pull-up resistor.

*1.

When the SCL input pin of the E

2PROM is connected to a tri-state output pin of the microprocessor,

connect the same pull-up resistor to prevent a high impedance status from being input to the SCL

input pin.

This protects the E

2PROM from malfunction due to an undefined output (high impedance) from the tri-

state pin when the microprocessor is reset when the voltage drops.

2. I/O pin equivalent circuit

The I/O pins of this IC do not include pull-up and pull-down resistors. The SDA pin is an open-drain output.

The following shows the equivalent circuits.

SCL

Figure 22 SCL Pin

SDA

Figure 23 SDA Pin

S24CS0 Datasheet(PDF) 20 Page - Seiko Instruments Inc