Infineon Technologies CY7C1148KV18-400BZC

Overview

CY7C1148KV18 from Cypress Semiconductor is a 18-Mbit (1M × 18) synchronous pipelined DDR II+ SRAM with two-word burst architecture, 2.0-cycle read latency, and 400 MHz clock operation. It features HSTL I/O, dual echo clocks (CQ/CQ), QVLD data-valid indicator, and PLL-based timing alignment for high-speed memory subsystems in networking and telecom line cards.

For engineers reviewing the CY7C1148KV18 datasheet, CY7C1148KV18 pinout, CY7C1148KV18 application, or CY7C1148KV18 equivalent, key selection criteria include DDR II+ burst timing compliance, 1.8 V core / 1.4–1.8 V I/O supply flexibility, FBGA-165 package compatibility, and DOFF-pin configurable latency mode (DDR I vs. DDR II+).

Technical Context

This SRAM implements a synchronous pipelined architecture where address and control signals are registered on K rising edges, while data transfers occur on both K and K rising edges-enabling true double-data-rate operation at 900 MT/s effective bandwidth. The internal 512K × 18 dual-array organization supports concurrent access to adjacent words within a burst.

The device integrates a phase-locked loop (PLL) for precise output data placement relative to echo clocks CQ/CQ, and uses ZQ calibration to match output impedance to system bus termination. DOFF pin selection determines whether the device operates in DDR II+ mode (2-cycle latency, up to 400 MHz) or legacy DDR I mode (1-cycle latency, ≤167 MHz).

Key Specifications

Pinout & Package

Available in 165-ball Fine-Pitch Ball Grid Array (FBGA) package, 13 mm × 15 mm × 1.4 mm body height, RoHS-compliant with Pb-free option.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C3256B-15JCIN and IS61WV102418BLL-10BLI, CY7C1148KV18 delivers 2× bandwidth via DDR II+, deterministic latency via PLL, and simplified data capture via CQ/CQ - making it optimal for new high-speed serial interface designs where timing margin is constrained.

Availability

CY7C1148KV18 is available at Aetrix Electronics and suitable for telecom line cards, packet switching hardware, wireless baseband processing, and automated test equipment requiring stable component supply and long-term lifecycle support.

Supply support for CY7C1148KV18 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 networking, automotive, and industrial applications, with emphasis on signal integrity and timing precision.

CY7C1148KV18 belongs to the QDR II+/DDR II+ SRAM product line, engineered specifically for deterministic, high-throughput memory interfaces in FPGA- and ASIC-based communications infrastructure.

FAQ

What is the function of the DOFF pin on CY7C1148KV18?

The DOFF pin controls the internal PLL: when asserted HIGH, the device operates in DDR II+ mode with 2.0-cycle read latency and supports up to 400 MHz clock frequency; when pulled LOW, the PLL is disabled and the device reverts to DDR I mode with 1-cycle latency and maximum 167 MHz operation. This allows hardware-selectable performance modes without firmware changes.

How does the ZQ pin affect output drive strength?

The ZQ pin connects to an external resistor to ground (typically 240 Ω) to calibrate the output driver impedance of DQ, CQ, and CQ pins to 0.2 × RQ (e.g., 48 Ω). This ensures consistent signal rise/fall times and minimizes reflections on high-speed PCB traces. Leaving ZQ unconnected or tying it to GND violates specification and may cause signal integrity failure.

Can CY7C1148KV18 be used without connecting the CQ and CQ pins?

No - CQ and CQ are mandatory for correct data capture. These echo clocks are phase-aligned to K/K and provide the timing reference for latching DQ[17:0] data in the controller. Omitting them forces reliance on board-level trace matching, which is impractical above 200 MHz and violates the DDR II+ interface specification.

What is the role of the QVLD signal during read operations?

QVLD is a synchronous output that asserts HIGH edge-aligned with CQ/CQ to indicate when DQ[17:0] carries valid data from the current burst word. It eliminates the need for fixed delay-based sampling windows and allows controllers to dynamically gate data capture - critical for maintaining timing margin across voltage, temperature, and process variation.