© 1996 Microchip Technology Inc.

DS21052F-page 7

24AA01/02

FIGURE 7-1:

CURRENT ADDRESS READ

FIGURE 7-2:

RANDOM READ

FIGURE 7-3:

SEQUENTIAL READ

SP

BUS ACTIVITY

MASTER

SDA LINE

BUS ACTIVITY

S

T

A

R

T

S

T

O

P

CONTROL

BYTE

DATA n

A

C

K

N

O

A

C

K

S

P

S

BUS ACTIVITY

MASTER

SDA LINE

BUS ACTIVITY

S

T

A

R

T

S

T

O

P

CONTROL

BYTE

A

C

K

WORD

ADDRESS (n)

CONTROL

BYTE

S

T

A

R

T

DATA (n)

A

C

K

A

C

K

N

O

A

C

K

P

BUS ACTIVITY

MASTER

SDA LINE

BUS ACTIVITY

S

T

O

P

CONTROL

BYTE

A

C

K

N

O

A

C

K

DATA n

DATA n + 1

DATA n + 2

DATA n + X

A

C

K

A

C

K

A

C

K

8.0

PIN DESCRIPTIONS

8.1

SDA Serial Address/Data Input/Output

This is a bi-directional pin used to transfer addresses

and data into and data out of the device. It is an open

drain terminal, therefore the SDA bus requires a pullup

Ω for 100 kHz, 1K for 400

kHz).

For normal data transfer SDA is allowed to change only

during SCL low.

Changes during SCL high are

reserved for indicating the START and STOP condi-

tions.

8.2

SCL Serial Clock

This input is used to synchronize the data transfer from

and to the device.

8.3

WP

(read/write the entire memory).

entire memory will be write-protected. Read operations

are not affected.

This feature allows the user to use the 24AA01/02 as a

8.4

A0, A1, A2

These pins are not used by the 24AA01/02. They may