Infineon Technologies CY7C199D-10ZXIT

Overview

CY7C199D-10ZXIT from Infineon Technologies (formerly Cypress) is a 256-Kbit (32K × 8) high-speed CMOS static RAM with 10 ns access time, TTL-compatible I/O, and automatic CE-controlled power-down. It operates at 5 V ±0.5 V over –40 °C to +85 °C, draws 80 mA active current and 3 mA CMOS standby current, and supports data retention down to 2.0 V. It is used in legacy industrial control systems requiring fast, reliable parallel memory interfacing with microcontrollers such as Intel 80Cxx or Motorola 68xxx families.

For engineers reviewing the CY7C199D-10ZXIT datasheet, CY7C199D-10ZXIT pinout, CY7C199D-10ZXIT application, or CY7C199D-10ZXIT equivalent, key selection considerations include its 28-pin TSOP I package, TTL-level input compatibility, 10 ns read/write cycle timing, automatic low-power deselection behavior, and absence of CMOS-level input support per AN6081.

Technical Context

The CY7C199D-10ZXIT implements a fully static asynchronous SRAM architecture with tri-state bidirectional I/Os (I/O0–I/O7), independent chip enable (CE), output enable (OE), and write enable (WE) controls. Its address decoding covers A0–A14 for 32,768 locations, and it uses complementary metal oxide semiconductor (CMOS) process technology optimized for speed/power trade-off at 5 V.

It features dual power-down modes: ISB1 (10 mA, TTL input thresholds) and ISB2 (3 mA, CMOS input thresholds), triggered automatically when CE is HIGH. Output drivers are TTL-compatible with VOH ≥ 2.4 V at –4 mA and VOL ≤ 0.4 V at 8 mA, but VIH minimum is only 2.2 V - insufficient for 5 V CMOS processors requiring ≥3.5 V VIH.

Key Specifications

Pinout & Package

Package: 28-pin thin small outline package (TSOP I), 8.0 mm × 13.4 mm body, 0.55 mm pitch, lead-free (Pb-free).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS6C4008-10PCN and IS61LV25616AL-10TLI, the CY7C199D-10ZXIT remains uniquely suitable for 5 V TTL-based legacy systems due to its native 5 V operation, pin-compatible footprint with CY7C199C, and guaranteed 10 ns timing at industrial temperature - neither alternative offers this combination.

Availability

CY7C199D-10ZXIT is available at Aetrix Electronics and suitable for industrial PLC memory buffers, legacy automotive ECU data loggers, and medical diagnostic display caches requiring stable component supply across extended product lifecycles.

Supply support for CY7C199D-10ZXIT 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

Infineon Technologies is a global semiconductor leader headquartered in Munich, Germany, specializing in power management, automotive ICs, and memory solutions formerly developed by Cypress Semiconductor.

The CY7C199D belongs to Infineon's legacy parallel SRAM product line, designed specifically for backward-compatible replacement of aging 5 V TTL memory in industrial and transportation control systems where long-term availability and proven reliability are mandatory.

FAQ

Is CY7C199D-10ZXIT compatible with 5 V CMOS microcontrollers?

No. The CY7C199D-10ZXIT specifies VIH(min) = 2.2 V, which falls below the 3.5 V minimum required by most 5 V CMOS processors. As documented in Application Note AN6081, interfacing with such devices requires external level-shifting or substitution with a CMOS-compatible SRAM like the IS61LV25616AL series.

What is the maximum clock frequency supported for burst reads?

The CY7C199D-10ZXIT is an asynchronous SRAM and does not use a clock signal. Its maximum effective throughput is determined by tRC = 10 ns, enabling up to 100 million read cycles per second when CE and OE are held active. Sustained burst operation requires strict adherence to tOHA (3 ns address hold) and tHZOE (5 ns high-Z delay) timing margins.

Does CY7C199D-10ZXIT support battery backup without external circuitry?

Yes. With VCC reduced to 2.0 V and CE held HIGH, the device retains stored data while drawing ≤3 mA (ISB2). A single CR2032 battery (220 mAh) can sustain retention for over 72 hours. No external power-switching logic is needed, but VCC must remain above 2.0 V during retention - brown-out detection is recommended.

Can CY7C199D-10ZXIT be used in place of CY7C199C?

Yes. The CY7C199D-10ZXIT is pin- and function-compatible with the CY7C199C, offering identical 32K × 8 organization, 28-pin TSOP I package, and TTL I/O levels. Key improvements include tighter tAA/tRC specifications (10 ns vs. 12 ns) and enhanced data retention characteristics, making it a direct upgrade path for existing CY7C199C designs.