3

5156E–SEEPR–10/08

AT24C01B

1.

Pin Description

SERIAL CLOCK (SCL): The SCL input is used to positive edge clock data into each EEPROM

device and negative edge clock data out of each device.

SERIAL DATA (SDA): The SDA pin is bidirectional for serial data transfer. This pin is open-

drain driven and may be wire-ORed with any number of other open-drain or open-collector

devices.

DEVICE/PAGE ADDRESSES (A2, A1, A0): The A2, A1 and A0 pins are device address inputs

that are hard wired for the AT24C01B. As many as eight 1K devices may be addressed on a sin-

gle bus system (device addressing is discussed in detail under the Device Addressing section).

WRITE PROTECT (WP): The AT24C01B has a write protect pin that provides hardware data

protection. The write protect pin allows normal read/write operations when connected to ground

(GND). When the write protect pin is connected to V

and operates as shown in Table 1-1.

Table 1-1.

Write Protect

2.

Memory Organization

AT24C01B, 1K SERIAL EEPROM: Internally organized with 16 pages of 8 bytes each, the 1K

requires an 7-bit data word address for random word addressing. (See Figure 8-2 on page 10)

WP Pin

Status

Part of the Array Protected

24C01B

At V

CC

Full (1K) Array

At GND

Normal Read/Write Operations