2

April 21, 2004

U634H256

Operating Mode

E

HSB

W

G

DQ0 - DQ7

Standby/not selected

H

H

**

High-Z

Internal Read

L

H

H

H

High-Z

Read

L

H

H

L

Data Outputs Low-Z

Write

L

H

L

*

Data Inputs High-Z

Truth Table for SRAM Operations

Block Diagram

Symbol

Min.

Max.

Unit

Power Supply Voltage

-0.5

7

V

Input Voltage

-0.3

V

Output Voltage

-0.3

V

Power Dissipation

1W

Operating Temperature

C-Type

K-Type

A-Type

M-Type

0

-40

-40

-55

70

85

125

125

°C

°C

°C

°C

Storage Temperature

-65

150

°C

Characteristics

All characteristics are valid in the power supply voltage range and in the operating temperature range specified.

Dynamic measurements are based on a rise and fall time of

a:

Stresses greater than those listed under „Absolute Maximum Ratings“ may cause permanent damage to the device. This is a stress

rating only, and functional operation of the device at condition above those indicated in the operational sections of this specification is

not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability.

EEPROM Array

512 x (64 x 8)

STORE

RECALL

SRAM

Array

512 Rows x

64 x 8 Columns

A0 - A13

Store/

Recall

Control

HSB

G

E

W

Software

Detect

Power

Control

A5

A6

A7

A8

A9

A11

A12

A13

DQ0

DQ1

DQ2

DQ3

DQ4

DQ5

DQ6

DQ7

Column I/O

Column Decoder

A0 A1 A2 A3 A4A10

A14