Infineon Technologies CY7C1568V18-400BZXC

Overview

CY7C1568V18 from Cypress Semiconductor is a 72-Mbit synchronous pipelined SRAM with DDR-II+ architecture, configured as 4M × 18, operating at 400 MHz with 2.5-cycle read latency and HSTL I/O. It delivers 800 MT/s effective data rate via double-data-rate transfers synchronized to K/K clocks and uses echo clocks (CQ/CQ) for precise high-speed data capture in burst-2 memory subsystems. It is deployed in network packet buffers and FPGA co-processor caches requiring deterministic low-latency access.

For engineers reviewing the CY7C1568V18 datasheet, CY7C1568V18 pinout, CY7C1568V18 application, or CY7C1568V18 equivalent, key selection criteria include 4M × 18 organization, 1.8V core / 1.4–1.8V I/O supply range, JTAG 1149.1 test port support, DLL-enabled timing alignment, and 165-ball FBGA (15 × 17 mm) mechanical compatibility.

Technical Context

The CY7C1568V18 implements a synchronous pipelined architecture where all address, control, and data signals are registered on rising edges of complementary K and K clocks. Its internal 2M × 18 dual-array structure enables burst-2 sequential reads/writes per access, with each transaction delivering two 18-bit words aligned to alternating K/K edges.

It integrates a Delay Lock Loop (DLL) for sub-cycle output skew control, echo clocks CQ/CQ phase-aligned to K/K for receiver-friendly data capture, and QVLD to indicate valid output timing. Write operations use on-chip self-timed logic, while ZQ pin enables dynamic output impedance calibration to match system bus termination.

Key Specifications

Pinout & Package

Package: 165-ball Fine-Pitch Ball Grid Array (FBGA), 15 mm × 17 mm × 1.4 mm body, 0.8 mm ball pitch, RoHS-compliant (Pb-free option available).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C36256A-15JIN and IS61WV102418BLL-10BLI, CY7C1568V18 uniquely delivers 72-Mbit density with DLL-aligned echo clocks and QVLD-enabling reliable 800 MT/s operation in FPGA-ASIC memory interconnects where timing closure is otherwise unattainable.

Availability

CY7C1568V18 is available at Aetrix Electronics and suitable for network packet buffering, FPGA co-processor caching, telecom baseband processing, and industrial motion control applications requiring stable component supply and long-term production continuity.

Supply support for CY7C1568V18 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, automotive, and industrial systems, with headquarters in San Jose, CA.

CY7C1568V18 belongs to Cypress's DDR-II+ SRAM product line, engineered specifically for deterministic, high-bandwidth memory interfacing in FPGA-ASIC co-processing architectures where traditional QDR or asynchronous SRAM fails to meet timing closure.

FAQ

What is the function of the DOFF pin on CY7C1568V18?

The DOFF pin disables the internal Delay Lock Loop when pulled LOW. In this state, the device reverts to DDR-I timing mode with maximum 167 MHz operation and relaxed setup/hold margins. For full DDR-II+ performance at 400 MHz, DOFF must be pulled HIGH via ≤10 kΩ resistor to VDDQ.

How does the ZQ pin affect output impedance calibration?

ZQ connects to a 240 Ω resistor to ground, enabling the device to calibrate its CQ, CQ, and Q[17:0] output drivers to 48 Ω (0.2 × 240 Ω). This matches standard HSTL-18 bus impedance, minimizing reflections and ensuring signal integrity at 800 MT/s. Leaving ZQ floating or tying to GND invalidates calibration.

Can CY7C1568V18 operate with only the K clock (not K)?

No. The CY7C1568V18 requires both K and K clocks for all synchronous operations. K initiates transactions and latches addresses/control; K captures second-half write data and drives second-word read output. Omitting K violates timing specifications and causes functional failure.

What is the purpose of the QVLD signal in system-level timing?

QVLD is a dedicated, edge-aligned indicator that asserts precisely when Q[17:0] data is valid and stable-synchronized to CQ/CQ rising edges. It eliminates reliance on fixed delay assumptions, allowing receivers (e.g., FPGA IDELAYCTRL) to dynamically gate data capture with zero timing margin uncertainty.