Infineon Technologies CY7C1327G-166AXC

Overview

CY7C1327G-166AXC from Cypress Semiconductor is a 4-Mbit (256K × 18) pipelined synchronous SRAM with registered I/O, 3.3 V core / 2.5 V I/O supplies, 3.5 ns clock-to-output delay at 166 MHz, and support for Intel Pentium™-compatible interleaved or linear burst sequences. It serves as high-speed secondary cache in embedded processor systems requiring deterministic timing and burst-mode memory access.

For engineers reviewing the CY7C1327G-166AXC datasheet, CY7C1327G-166AXC pinout, CY7C1327G-166AXC application, or CY7C1327G-166AXC equivalent, key selection criteria include synchronous self-timed write capability, dual address strobe support (ADSP/ADSC), user-selectable burst mode via MODE pin, and ZZ sleep mode with data retention - all critical for cache subsystem integration in legacy x86 and industrial control platforms.

Technical Context

The device implements a two-bit wraparound burst counter synchronized to CLK's rising edge, enabling automatic internal address generation during burst reads/writes. All synchronous inputs - including A[1:0], CE1–CE3, ADSP/ADSC, ADV, BW[A:B], BWE, and GW - are registered on the same clock edge, ensuring precise timing alignment across pipeline stages.

It supports byte-write granularity via BWE and BW[A:B] with global write override (GW), and features asynchronous OE for output tristating independent of clock phase. The ZZ pin places the device in low-power sleep while preserving data integrity, though per errata (Rev. *Q, p.21), Pin 64 must be externally tied to ground for reliable operation.

Key Specifications

Pinout & Package

Package: 100-pin TQFP (14 mm × 14 mm, 0.5 mm pitch), RoHS-compliant, Pb-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT71V2576S166BG and IS61WV25618BLL-166TQLI, the CY7C1327G-166AXC uniquely combines dual address strobes, hardware-configurable burst mode, and errata-managed ZZ sleep - making it the only drop-in solution for legacy Pentium-based cache subsystems requiring all three features.

Availability

CY7C1327G-166AXC is available at Aetrix Electronics and suitable for secondary cache subsystems, industrial motion controller buffers, communications protocol accelerators, and avionics data logger interfaces requiring stable component supply and long-term lifecycle support.

Supply support for CY7C1327G-166AXC 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 communications markets, with emphasis on timing-critical embedded subsystems.

The CY7C1327G belongs to Cypress's legacy synchronous SRAM product line, engineered specifically for deterministic-burst cache applications in x86-compatible and real-time control systems where pipelined latency and dual-bus compatibility are mandatory.

FAQ

What is the correct configuration for the ZZ pin on CY7C1327G-166AXC?

The ZZ pin (Pin 64) must be externally connected to ground per documented errata (Rev. *Q, page 21). Although described as active-HIGH sleep input, leaving it floating or pulling it HIGH causes unreliable behavior. Grounding ensures stable operation and prevents unintended entry into sleep mode during normal use.

Does CY7C1327G-166AXC support true 166 MHz operation with 3.5 ns tCO under all conditions?

Yes - the 3.5 ns clock-to-output time is guaranteed over commercial temperature range (0°C to +70°C) and VDD = 3.3 V ± 0.3 V, VDDQ = 2.5 V ± 0.2 V, with CL = 30 pF and specified AC test loads. This value applies only to pipelined read cycles following valid ADSP/ADSC assertion and proper chip enable timing.

How does burst addressing work when MODE is set to linear versus interleaved?

In linear mode (MODE = GND), burst addresses increment sequentially: A, A+1, A+2, A+3. In interleaved mode (MODE = VDD/floating), they follow Pentium order: A, A+2, A+0, A+3 - optimized for 32-bit data bus alignment. The 2-bit internal counter wraps automatically after four beats, and ADV controls advancement timing.

Can CY7C1327G-166AXC perform byte writes without external write strobe logic?

Yes - byte writes are fully managed on-chip using BWA/BWB (byte select), BWE (enable), and GW (global override). When BWE = LOW and BW[A:B] selects specific bytes, only those bytes are written; GW = LOW forces all four 18-bit words to update. No external write pulse generator or timing circuitry is needed due to synchronous self-timed write architecture.