Infineon Technologies CY7C1565KV18-400BZI

Overview

CY7C1565KV18-400BZI from Cypress Semiconductor is a 72-Mbit (2M × 36) QDR® II+ SRAM with four-word burst architecture, 2.5-cycle read latency, and dual DDR interfaces operating at 400 MHz (800 MT/s effective data rate). It features separate read/write ports, echo clocks (CQ/CQ), QVLD data-valid indicator, and PLL-based timing alignment - deployed in high-bandwidth packet buffering for network switches and routers.

For engineers reviewing the CY7C1565KV18-400BZI datasheet, CY7C1565KV18-400BZI pinout, CY7C1565KV18-400BZI application, or CY7C1565KV18-400BZI equivalent, key selection criteria include 1.8-V core / 1.4–1.8-V I/O supply compatibility, 165-ball FBGA (13 × 15 mm) package constraints, QDR II+ vs. QDR I mode switching via DOFF pin, and synchronous depth expansion using RPS/WPS controls.

Technical Context

The device implements a true quad data rate architecture with independent read and write ports sharing a multiplexed 19-bit address bus. All synchronous inputs (RPS, WPS, BWS[3:0], A[18:0], D[35:0]) are registered on rising edges of K and K clocks, while outputs (Q[35:0], QVLD, CQ, CQ) are edge-aligned to those same clocks. The internal PLL enables precise 2.5-cycle read latency when DOFF = HIGH.

Each read access delivers four sequential 36-bit words over two clock cycles (DDR), achieving full data coherency without bus turnaround. Write operations are self-timed and support byte-selectable writes via BWS[3:0], with dedicated port selects enabling depth expansion across multiple devices without external logic.

Key Specifications

Pinout & Package

Package: 165-ball fine-pitch ball grid array (FBGA), 13 mm × 15 mm × 1.4 mm body, 0.8 mm ball pitch, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C36256P-15JIN and IS61WV102436BLL-15BLI, CY7C1565KV18-400BZI uniquely delivers concurrent DDR read/write at 400 MHz with hardware-managed timing (CQ/QVLD/PLL), making it irreplaceable in line-rate packet processing where bus turnaround and jitter-limited capture are design-critical.

Availability

CY7C1565KV18-400BZI is available at Aetrix Electronics and suitable for network packet buffering, telecom line card memory, baseband processing cache, and ATE pattern memory requiring stable component supply across multi-year production cycles.

Supply support for CY7C1565KV18-400BZI 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.

The QDR® II+ SRAM product line targets deterministic, low-latency, high-throughput memory subsystems in infrastructure equipment - specifically engineered to replace asynchronous SRAMs and simplify DDR interface timing in FPGA- and ASIC-based datapaths.

FAQ

What is the function of the DOFF pin, and how does it affect timing?

The DOFF pin disables the internal PLL when asserted LOW, forcing the device into QDR I mode with 1-cycle read latency and a maximum frequency of 167 MHz. When DOFF is HIGH (default), the PLL enables 2.5-cycle latency and full 400 MHz operation. Pulling DOFF HIGH via ≤10 kΩ resistor is required for QDR II+ functionality; leaving it floating or tied LOW invalidates QDR II+ timing specifications.

How does the ZQ pin configure output drive strength?

ZQ connects to an external resistor (RQ) to ground, setting CQ, CQ, and Q[35:0] output impedance to 0.2 × RQ - typically 40 Ω for 200 Ω RQ. Alternatively, tying ZQ to VDDQ enables minimum impedance mode (~20 Ω). ZQ must never be left floating or connected to GND, as this disables impedance calibration and risks signal integrity failure.

Can CY7C1565KV18-400BZI operate with only one clock input?

No. The device requires both K and K differential clock inputs for correct DDR operation: K clocks read-port signals (RPS, A, Q[35:0], CQ), and K clocks write-port signals (WPS, BWS[3:0], D[35:0], CQ). Using only one clock violates timing specifications and prevents valid data capture on either port.

What happens to Q[35:0] when RPS is deasserted mid-burst?

When RPS is deasserted, the current read burst completes normally, and Q[35:0] drivers are tri-stated on the next rising edge of K. No partial or corrupted words are driven; the final word of the four-word burst remains valid until tri-state activation. This ensures clean bus release without glitches or contention.