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©

1992

MOS INTEGRATED CIRCUIT

256K-BIT CMOS STATIC RAM

32K-WORD BY 8-BIT

DATA SHEET

Document No. M10693EJ7V0DS00 (7th edition)

Date Published June 2000 NS CP (K)

Printed in Japan

The mark 5 shows major revised points.

Description

The

µPD43257B is a high speed, low power, and 262,144 bits (32,768 words by 8 bits) CMOS static RAM.

Battery backup is available. And the

µPD43257B has two chip enable pins (/CE1, CE2) to extend the capacity.

The

µPD43257B is packed in 28-pin plastic DIP and 28-pin plastic SOP.

Features

• 32,768 words by 8 bits organization

• Fast access time: 70, 85 ns (MAX.)

• Two Chip Enable inputs: /CE1, CE2

Part number

Access time

Operating supply

Operating ambient

Supply current

ns (MAX.)

voltage

temperature

At operating

At standby

At data retention

V

°C

mA (MAX.)

µA (MAX.)

µPD43257B-xxL

70, 85

4.5 to 5.5

0 to 70

45

50

3

µPD43257B-xxLL

45

15

2

Note

Version X

This Data sheet can be applied to the version X. This version is identified with its lot number. Letter X in the fifth

character position in a lot number signifies version X.

X

D43257B

Lot number

JAPAN