描述 Description

The TC55257CPI is a 262,144 bit CMOS static random access memory organized as 32,768 words by 8 bits and operated from a

single 5V power supply. Advanced circuit techniques provide both high speed and low power features with an operating current of

5mA/MHz (typ.) and a minimum cycle time of 85ns.

When CE is a logical high, the device is placed in a low power standby mode in which the standby current is 2uA at room tem-

perature. The TC55257CPI has two control inputs. Chip enable (CE) allows for device selection and data retention control, while an

output enable input (OE) provides fast memory access. The TC55257CPI is suitable for use in microprocessor systems where high

speed, low power, and battery backup are required. The TC55257CPI is guaranteed over an operating temperature range

of -40 - 85°C so the TC55257CPI is suitable for use in wide operating temperature systems.

The TC55257CPI is offered in a standard dual-in-line 28-pin plastic package (0.6/0.3 inch width), a small outline plastic pack-

age, and a thin small outline plastic package (forward type, reverse type).

特性 Features

Low power dissipation:

Standby current:

Single 5V power supply

? Access time (max.)

Access Time

CE Access Time

OE Access Time

27.5mW/MHz (typ.)

200μA (max.)

Pin Names

TC55257CPI/CFI/CSPI/CFTI/CTRI

-85

85ns

85ns

45ns

Power down feature:

CE

Data retention supply voltage:

Inputs and outputs TTL compatible

? Wide operating temperature: -40 - 85°C

Package

TC55257CPI

TC55257CFI

TC55257CSPI

TC55257CFTI

TC55257CTRI

-10

100ns

100ns

50ns

2.0-5.5V

: DIP28-P-600

: SOP28-P-450

: DIP28-P-300B

: TSOP28-P

: TSOP28-P-A