Infineon Technologies CY7C1347G-250AXCT

Overview

CY7C1347G-250AXCT from Infineon Technologies (formerly Cypress) is a 4-Mbit (128K × 36) pipelined synchronous SRAM optimized for zero-wait-state secondary cache in high-speed computing systems. It operates with a 3.3 V core supply (VDD), 2.5 V/3.3 V I/O supply (VDDQ), delivers 2.6 ns clock-to-output delay at 250 MHz, supports Intel Pentium–style interleaved or PowerPC-style linear burst sequences via MODE pin, and is packaged in Pb-free 100-pin TQFP.

For engineers reviewing the CY7C1347G-250AXCT datasheet, CY7C1347G-250AXCT pinout, CY7C1347G-250AXCT application, or CY7C1347G-250AXCT equivalent, key selection criteria include synchronous burst timing control, dual-voltage I/O tolerance, ZZ sleep mode implementation, and CE1/CE2/CE3 bank-select logic for multi-chip cache architectures.

Technical Context

The device implements fully registered synchronous interfaces: all address, control, and data inputs are latched on the rising edge of CLK, and all outputs pass through output registers synchronized to the same edge. Its 2-bit wraparound burst counter captures A[1:0] at burst initiation and auto-increments for subsequent accesses within the 36-bit-wide data path.

Burst sequencing is statically selected by the MODE pin (GND = linear; VDDQ/floating = interleaved), while write operations are managed via synchronous self-timed circuitry using GW (global write) and BWE/BW[A:D] (byte-write enable/select). ADSP and ADSC provide independent address strobe paths for processor- and controller-initiated accesses, with ADV controlling address advancement during bursts.

Key Specifications

Pinout & Package

Supplied in a Pb-free 100-pin Thin Quad Flat Package (TQFP) with 0.5 mm pitch, thermal pad exposed on underside for enhanced heat dissipation in sustained cache operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous SRAM applications.

Compared with IS61WV102436B-250TQLI, CY7C1347G-250AXCT provides VDDQ flexibility and power-managed sleep, while MC10E131FN serves a fundamentally different purpose - it is a latch, not an SRAM - making it unsuitable for cache or buffering roles requiring memory storage.

Availability

CY7C1347G-250AXCT is available at Aetrix Electronics and suitable for Intel Pentium-based cache subsystems, PowerPC embedded controller caches, multi-bank memory expansion modules, and high-reliability industrial data buffers requiring stable component supply and long-term lifecycle support.

Supply support for CY7C1347G-250AXCT 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, industrial, and memory solutions with emphasis on reliability and industrial-grade performance.

The CY7C1347G belongs to Infineon's legacy synchronous SRAM product line, originally developed by Cypress to address high-bandwidth, low-latency cache requirements in x86 and RISC-based computing platforms.

FAQ

What is the correct configuration for the ZZ pin on CY7C1347G-250AXCT?

The ZZ pin (Pin 64) must be externally connected to ground during normal operation, as specified in the device errata (Page 22). Although described as an active-HIGH sleep input, the silicon revision requires this connection to ensure stable operation - leaving it floating or pulling it HIGH may cause functional failure. Internal pull-down ensures safe default state, but external grounding is mandatory per documented erratum.

How does the CY7C1347G-250AXCT handle burst address advancement?

Burst address advancement is controlled exclusively by the ADV input, sampled synchronously on the rising edge of CLK. When ADV is asserted LOW, the internal 2-bit wraparound burst counter increments automatically. The counter captures A[1:0] at burst initiation and supports four consecutive addresses in either linear or interleaved order, depending on MODE pin state - no external counter or glue logic is required.

Can CY7C1347G-250AXCT operate with VDDQ = 2.5 V while interfacing to 3.3 V logic?

Yes. When VDDQ = 2.5 V, all I/O pins (DQA–DQD, DQPA–DQPD, BWA–BWD, etc.) are 3.3 V tolerant, allowing direct connection to 3.3 V drivers without level shifters. This is explicitly guaranteed in the datasheet's "Functional Description" section and verified under Electrical Characteristics for VDDQ = 2.5 V operation.

What is the role of CE2 being active HIGH while CE1 and CE3 are active LOW?

CE2's active-HIGH polarity enables complementary decoding logic in multi-SRAM bank designs - for example, using a single 3-to-8 decoder where one output drives CE2 HIGH while others drive CE1/CE3 LOW. This asymmetry simplifies address decode mapping and avoids requiring inverters on one chip select line, reducing board-level component count and signal propagation skew.