Infineon Technologies CY7C168A-20PXC

Overview

CY7C168A-20PXC from Cypress Semiconductor is a 4 K × 4-bit (16 Kbit) CMOS static RAM with 20 ns access time, TTL-compatible I/O, and automatic CE-controlled power-down reducing standby current to 20 mA. It operates at 5 V ±10% over 0°C to +70°C and is used in legacy industrial controllers, instrumentation buffers, and microprocessor-based data acquisition systems requiring non-volatile SRAM interface compatibility.

For engineers reviewing the CY7C168A-20PXC datasheet, CY7C168A-20PXC pinout, CY7C168A-20PXC application, or CY7C168A-20PXC equivalent, key selection criteria include tAA ≤ 20 ns read timing, CE/WE dual-control write architecture, I/O0–I/O3 bidirectional data bus behavior, and automatic ISB2 = 20 mA power-down under CE > VCC − 0.3 V.

Technical Context

The CY7C168A-20PXC implements a 128 × 128 memory array with separate row/column decoders and sense amplifiers. Its operation relies on synchronous CE and WE logic: CE LOW + WE HIGH enables read mode with data valid within tAA = 20 ns; CE LOW + WE LOW initiates write with data latched on the rising edge of whichever signal goes HIGH first.

Power management is hardware-automated: when CE rises above VCC − 0.3 V, internal circuitry forces ISB2 ≤ 20 mA standby draw without external control. Input buffers accept VIH ≥ 2.2 V and tolerate −3.0 V pulses <30 ns; output drivers deliver VOH ≥ 2.4 V at −4 mA and VOL ≤ 0.4 V at 8 mA.

Key Specifications

Pinout & Package

Package: 20-pin plastic DIP (Dual In-line Package), 0.600-inch width, through-hole mounting.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar static RAM applications.

Compared with AS6C4008-20ZIN and IS61LV25616AL-20TQLI, the CY7C168A-20PXC uniquely delivers 5 V compatibility, 4-bit bus alignment, and hardware-automated standby-making it irreplaceable in legacy 5 V controller upgrades where pin count, voltage, and power sequencing are fixed.

Availability

CY7C168A-20PXC is available at Aetrix Electronics and suitable for industrial PLC data buffering, legacy microcontroller memory expansion, and medical diagnostic equipment cache requiring stable component supply across extended product lifecycles.

Supply support for CY7C168A-20PXC includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Cypress Semiconductor, now part of Infineon Technologies, designs high-reliability memory and programmable solutions for industrial, automotive, and aerospace applications.

The CY7C168A belongs to Cypress's legacy CMOS SRAM product line, engineered specifically for drop-in replacement of bipolar and NMOS memories in 5 V systems requiring TTL compatibility and deterministic timing.

FAQ

Is CY7C168A-20PXC compatible with 3.3 V logic interfaces?

No. The CY7C168A-20PXC is specified only for 5 V ±10% operation. Its VIH minimum is 2.2 V, but VOH and VOL are characterized at VCC = 5 V, and input clamp diodes are not rated for 3.3 V interface safety. Direct connection to 3.3 V devices risks latch-up or excessive current draw.

What happens to data during automatic power-down?

Data retention is fully maintained during automatic power-down. When CE rises above VCC − 0.3 V, the device enters low-current standby (ISB2 ≤ 20 mA) but retains all stored bits indefinitely as long as VCC remains within 4.5 V to 5.5 V and ambient temperature stays within 0°C to +70°C.

Can I/O0–I/O3 be used as independent single-bit lines?

No. I/O0–I/O3 operate strictly as a 4-bit bidirectional data bus. They share common direction control via CE and WE states and cannot be individually tri-stated or driven. Each pin reflects the same 4-bit word during read or write cycles.

Does CY7C168A-20PXC require an external clock signal?

No. The CY7C168A-20PXC is a static RAM and operates asynchronously. All timing is controlled by CE and WE signal edges relative to address stability; no clock input or timing generator is required.