S-24C02BPPHL Datasheet, PDF (19/39 Pages) Seiko Instruments Inc – 2-WIRE CMOS SERIAL E2PROM

Rev.2.2_00
2-WIRE CMOS SERIAL E²PROM
S-24C02BPPHL
„ Using S-24C02BPPHL
1. Adding a pull-up resistor to SDA I/O pin and SCL input pin
Add a 1 kΩ to 5 kΩ pull-up resistor to the SCL input pin^*1 and the SDA I/O pin in order to enable the
functions of the I²C-BUS protocol. Normal communication cannot be provided without a pull-up resistor.
*1. When the SCL input pin of the E²PROM 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 E²PROM from malfunction due to an undefined output (high impedance) from the tri-
state pin when the microprocessor is reset when the voltage drops.
2. Slave address
The S-24C02BPPHL does not have slave address pins (A0, A1, A2). Therefore two or more of this IC cannot
be used on the same bus.
However, slave addresses can be used without changing the communication software because they are
arbitrary addresses in communication with the master device.
SDA line 1
0
1
0
X
X
X R/W ACK
MSB
Don’t care
LSB
Figure 18
Seiko Instruments Inc.
19