CAT28HT256 Datasheet, PDF (1/10 Pages) Catalyst Semiconductor – 256K-Bit CMOS PARALLEL E2PROM

Advanced
CAT28HT256
256K-Bit CMOS PARALLEL E²PROM
Extended Temperature: 170˚C
FEATURES
s Fast Read Access Times: 200/250 ns
s Low Power CMOS Dissipation:
–Active: 30 mA Max.
–Standby: 150 µA Max.
s Simple Write Operation:
–On-Chip Address and Data Latches
–Self-Timed Write Cycle with Auto-Clear
s Fast Write Cycle Time:
–10ms Max
s CMOS and TTL Compatible I/O
s Automatic Page Write Operation:
–1 to 64 Bytes in 10ms
–Page Load Timer
s End of Write Detection:
–Toggle Bit
–DATA Polling
s Hardware and Software Write Protection
s 100,000 Program/Erase Cycles
s 100 Year Data Retention
DESCRIPTION
The CAT28HT256 is a fast, low power, 5V-only CMOS
parallel E²PROM organized as 32K x 8-bits. It requires
a simple interface for in-system programming. On-chip
address and data latches, self-timed write cycle with
auto-clear and VCC power up/down write protection
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
A6–A14
ADDR. BUFFER
& LATCHES
VCC
CE
OE
WE
INADVERTENT
WRITE
PROTECTION
CONTROL
LOGIC
A0–A5
TIMER
ADDR. BUFFER
& LATCHES
ROW
DECODER
HIGH VOLTAGE
GENERATOR
DATA POLLING
AND
TOGGLE BIT
COLUMN
DECODER
32,768 x 8
E²PROM
ARRAY
64 BYTE PAGE
REGISTER
I/O BUFFERS
I/O0–I/O7
5096 FHD F02
© 1998 by Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
8-91