Overview

The LC35256FM and LC35256FT are asynchronous silicon-gate CMOS SRAMs with a 32K-word by 8-bit structure. These are full-CMOS devices with 6 transistors per memory cell, and feature low-voltage operation, a low operating current drain, and an ultralow standby current. Control inputs include OE for fast memory access and CE (chip enable) for power saving and device selection. This makes these devices optimal for systems that require low power or battery backup, and makes memory expansion easy. The ultralow standby current allows these devices to be used with capacitor backup as well.

Features

• Supply voltage range: 4.5 to 5.5 V

• Access time at 5 V operation:

  LC35256FM, FT-55U: 55 ns (maximum)

  LC35256FM, FT-70U: 70 ns (maximum)

• Standby current: 3.0 µA (Ta ≤70°C)

                         5.0 µA (Ta ≤85°C)

• Operating temperature: –40 to +85°C

• Data retention voltage: 2.0 to 5.5 V

• All I/O levels: TTL compatible

• Input/output shared function pins, 3-state output pins

• No clock required

• Package

  28-pin SOP (450 mil) plastic package: LC35256FM

  28-pin TSOP (8 ×13.4 mm) plastic package: LC35256FT