Infineon Technologies CY7C1270V18-400BZXC

Overview

CY7C1270V18 from Cypress Semiconductor is a 36-Mbit (1M × 36) synchronous pipelined SRAM with DDR-II+ architecture, operating at 400 MHz clock frequency and delivering 800 MHz effective data rate via double-data-rate interface. It features 2.5-cycle read latency, HSTL I/O with variable drive strength, and dual echo clocks (CQ/CQ) for precise high-speed data capture in memory subsystems. Used in network packet buffers and high-throughput FPGA-attached memory interfaces.

For engineers reviewing the CY7C1270V18 datasheet, CY7C1270V18 pinout, CY7C1270V18 application, or CY7C1270V18 equivalent, key selection criteria include its 1M × 36 organization, 1.8V core / 1.4–1.8V I/O supply range, JTAG 1149.1 test port, DLL-enabled timing alignment, and 165-ball FBGA package compatibility with depth-expanded memory designs.

Technical Context

This SRAM implements a synchronous burst architecture where all address, control, and data transfers are edge-aligned to K and K clocks. Read and write operations are fully pipelined, with addresses latched on alternating rising edges of K/K and data transferred on both edges-enabling continuous 2-word bursts without bus turnaround overhead.

The device integrates a Delay Lock Loop (DLL) for sub-cycle output skew control, echo clocks synchronized to input clocks for simplified board-level timing closure, and QVLD signal for cycle-accurate data validity indication. Byte write select inputs (BWS[3:0]) enable granular 8-bit write masking across the 36-bit data bus.

Key Specifications

Pinout & Package

Package: 165-ball Fine-Pitch Ball Grid Array (FBGA), 15 mm × 17 mm × 1.4 mm body, RoHS-compliant, with 0.8 mm ball pitch and standard JEDEC MO-245 footprint.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1270V18-333BZXC, the -400BZXC delivers 20% higher bandwidth and tighter timing margins via DLL; versus AS7C336400B-400BIN, it simplifies timing closure with echo clocks and QVLD but lacks true dual-port concurrency.

Availability

CY7C1270V18-400BZXC is available at Aetrix Electronics and suitable for network packet buffers, FPGA co-processor memory, and telecom baseband processing requiring stable component supply across extended product lifecycles.

Supply support for CY7C1270V18-400BZXC 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-performance memory and programmable solutions for communications, industrial, and automotive systems.

The CY7C12xxV18 family targets high-speed memory subsystems demanding deterministic latency, DDR bandwidth, and robust signal integrity - specifically engineered for FPGA- and ASIC-based infrastructure equipment.

FAQ

What is the function of the DOFF pin on CY7C1270V18?

The DOFF pin disables the internal Delay Lock Loop when pulled LOW. In this mode, the device operates as a DDR-I SRAM with maximum clock frequency of 167 MHz and relaxed timing parameters. For full 400 MHz DDR-II+ operation, DOFF must be tied HIGH via ≤10 kΩ pull-up resistor to VDDQ.

How does the ZQ pin affect output driver impedance?

ZQ connects to an external resistor (RQ) to ground, calibrating CQ, CQ, and DQ output drivers to 0.2 × RQ. This achieves precise HSTL-compatible impedance matching (e.g., 25 Ω for 125 Ω RQ). If RQ is omitted, ZQ may be tied to VDDQ to enable minimum-impedance mode, but not to VSS or left floating.

Can CY7C1270V18 operate with only the K clock?

No - K and K are complementary differential clocks both required for normal DDR-II+ operation. The device uses rising edges of both clocks to latch inputs and drive outputs. Omitting K violates timing specifications and prevents functional operation; K alone cannot substitute for the K/K pair.

What is the purpose of the QVLD signal in read transactions?

QVLD is asserted edge-aligned with CQ and CQ to indicate when DQ[35:0] carries valid read data. It eliminates the need for fixed delay-based sampling or complex strobe recovery circuits, allowing receivers to gate data capture precisely on QVLD assertion - critical for reliable 800 MT/s operation.