8-91

CAT28HT256

FEATURES

–Active: 30 mA Max.

–Standby: 150

–On-Chip Address and Data Latches

–Self-Timed Write Cycle with Auto-Clear

–10ms Max

–1 to 64 Bytes in 10ms

–Page Load Timer

–Toggle Bit

–

DATA

DATA

DATA

DATA

DATA Polling

DESCRIPTION

The CAT28HT256 is a fast, low power, 5V-only CMOS

a simple interface for in-system programming. On-chip

address and data latches, self-timed write cycle with

eliminate additional timing and protection hardware.

DATA Polling and Toggle status bits signal the start and

end of the self-timed write cycle. Additionally, the

CAT28HT256 features hardware and software write

protection as well as an internal Error Correction Code

(ECC) for extremely high reliability.

The CAT28HT256 is manufactured using Catalyst’s

advanced CMOS floating gate technology. It is designed

to endure 100,000 program/erase cycles and has a data

retention of 100 years. The device is available in JEDEC

approved 28-pin Ceramic DIP package.

BLOCK DIAGRAM

5096 FHD F02

© 1998 by Catalyst Semiconductor, Inc.

Characteristics subject to change without notice

Advanced

Extended Temperature: 170˚C

ADDR. BUFFER

& LATCHES

ADDR. BUFFER

& LATCHES

INADVERTENT

WRITE

PROTECTION

CONTROL

LOGIC

TIMER

ROW

DECODER

COLUMN

DECODER

HIGH VOLTAGE

GENERATOR

A6–A14

CE

OE

WE

A0–A5

I/O0–I/O7

I/O BUFFERS

32,768 x 8

ARRAY

64 BYTE PAGE

REGISTER

VCC

DATA POLLING

AND

TOGGLE BIT