IS24C02A データシートの表示（PDF） - Integrated Silicon Solution

部品番号

コンポーネント説明

メーカー

IS24C02A

1K-bit/2K-bit/4K-bit/8K-bit/16K-bit 2-WIRE SERIAL CMOS EEPROM

Integrated Silicon Solution 

IS24C02A IS24C04A IS24C08A IS24C16A

ISSI ®

DEVICE OPERATION

IS24C02A/04A/08A/16A features serial communication and

supports a bi-directional 2-wire bus transmission protocol

called I2CTM.

2-WIRE BUS

The two-wire bus is defined as a Serial Data line (SDA), and

a Serial Clock line (SCL). The protocol defines any device that

sends data onto the SDA bus as a transmitter, and the

receiving devices as receivers. The bus is controlled by

Master device that generates the SCL, controls the bus

access, and generates the Stop and Start conditions. The

IS24C02A/04A/08A/16A is the Slave device on the bus.

The Bus Protocol:

– Data transfer may be initiated only when the bus is not busy

– During a data transfer, the SDA line must remain stable

whenever the SCL line is high. Any changes in the SDA

line while the SCL line is high will be interpreted as a Start

or Stop condition.

The state of the SDA line represents valid data after a Start

condition. The SDA line must be stable for the duration of the

High period of the clock signal. The data on the SDA line may

be changed during the Low period of the clock signal. There

is one clock pulse per bit of data. Each data transfer is

initiated with a Start condition and terminated with a Stop

condition.

Start Condition

The Start condition precedes all commands to the device and

is defined as a High to Low transition of SDA when SCL is High.

The EEPROM monitors the SDA and SCL lines and will

not respond until the Start condition is met.

Stop Condition

The Stop condition is defined as a Low to High transition

of SDA when SCL is High. All operations must end with

a Stop condition.

Acknowledge (ACK)

After a successful data transfer, each receiving device is

required to generate an ACK. The Acknowledging device

pulls down the SDA line.

Reset

The IS24C02A/04A/08A/16A contains a reset function

in case the 2-wire bus transmission is accidentally

interrupted (eg. a power loss), or needs to be

terminated mid-stream. The reset is caused when the

Master device creates a Start condition. To do this, it

may be necessary for the Master device to monitor the

SDA line while cycling the SCL up to nine times. (For

each clock signal transition to High, the Master checks

for a High level on SDA.)

Standby Mode

Power consumption is reduced in standby mode. The

IS24C02A/04A/08A/16A will enter standby mode: a) At

Power-up, and remain in it until SCL or SDA toggles; b)

Following the Stop signal if a no write operation is

initiated; or c) Following any internal write operation.

4

Integrated Silicon Solution, Inc. — www.issi.com — 1-800-379-4774

Rev. F

01/09/06

Share Link: