Cypress Semiconductor Corp CY7C1565KV18-400BZXC

Overview

CY7C1565KV18-400BZXC from Cypress Semiconductor is a 72-Mbit QDR® II+ SRAM with 2M × 36 organization, four-word burst architecture, and 2.5-cycle read latency. It features separate read/write ports, DDR interfaces on both ports (1100 MHz effective data rate at 550 MHz clock), and operates with core VDD = 1.8 V ± 0.1 V and I/O VDDQ = 1.4–1.8 V. Used in high-bandwidth packet buffering for network switches and routers.

For engineers reviewing the CY7C1565KV18-400BZXC datasheet, CY7C1565KV18-400BZXC pinout, CY7C1565KV18-400BZXC application, or CY7C1565KV18-400BZXC equivalent, key selection criteria include 550-MHz maximum clock frequency, QDR II+ 2.5-cycle latency mode, echo clocks (CQ/CQ) for timing margin, DOFF-controlled PLL enable/disable, and 165-ball FBGA package compatibility with HSTL-18 I/O.

Technical Context

The CY7C1565KV18-400BZXC implements a synchronous pipelined QDR II+ architecture with independent read and write ports sharing a multiplexed 19-bit address bus. Each port uses DDR interfaces synchronized to complementary K/K clocks, enabling concurrent read and write transactions without bus turnaround.

It integrates an internal PLL for precise data placement and supports two operational modes: QDR II+ mode (DOFF = HIGH, 2.5-cycle read latency) and QDR I mode (DOFF = LOW, 1-cycle latency up to 167 MHz). Echo clocks CQ/CQ are free-running and edge-aligned with K/K to simplify high-speed data capture.

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 QDR II+ SRAM applications.

Compared with AS7C35128A-400BIN and IS61WV102436B-400TQLI, the CY7C1565KV18-400BZXC uniquely delivers true dual-port QDR II+ operation with programmable latency, echo clocks, and 72-Mbit density-enabling deterministic, full-duplex memory access at 400 MHz that neither alternative supports.

Availability

CY7C1565KV18-400BZXC is available at Aetrix Electronics and suitable for network packet buffering, telecom line card memory, baseband processing memory, and high-speed test equipment FIFO requiring stable component supply and long-term industrial availability.

Supply support for CY7C1565KV18-400BZXC 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) is a U.S.-based semiconductor company specializing in high-performance memory, microcontrollers, and connectivity solutions for industrial, automotive, and communications markets.

The CY7C1565KV18 belongs to Cypress's QDR II+ SRAM product line, engineered specifically for deterministic, high-bandwidth, low-latency memory subsystems in networking infrastructure and telecom equipment where concurrent read/write throughput is critical.

FAQ

What is the function of the DOFF pin on CY7C1565KV18-400BZXC?

The DOFF (PLL Disable) pin controls the internal phase-locked loop: when pulled HIGH, the PLL is enabled and the device operates in QDR II+ mode with 2.5-cycle read latency at up to 400 MHz; when pulled LOW, the PLL is disabled and the device reverts to QDR I mode with 1-cycle latency but limited to ≤167 MHz. This pin must be externally pulled up via ≤10 kΩ resistor for normal operation.

How does the ZQ pin affect output drive strength?

The ZQ pin connects to an external resistor (RQ) tied to ground to calibrate the output impedance of Q[35:0], CQ, and CQ pins to 0.2 × RQ. For example, a 100 Ω RQ sets output impedance to 20 Ω. Alternatively, tying ZQ directly to VDDQ enables minimum impedance mode. ZQ must never be left floating or connected to GND, as this disables calibration and risks signal integrity failure.

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

No. The device requires both K and K complementary clock inputs for correct operation: K controls read-port timing (RPS, A, Q[35:0]), while K controls write-port timing (WPS, BWS[3:0], D[35:0]). Using only one clock violates the QDR II+ architecture and causes undefined behavior, including potential data corruption or port lockup. Both clocks must be present and properly phased.

What is the purpose of the QVLD signal during burst reads?

QVLD is a synchronous, edge-aligned output that asserts HIGH on the same rising edge of CQ/CQ when corresponding Q[35:0] data is valid. It eliminates the need for fixed delay-based data capture windows, allowing external logic to sample Q[35:0] with zero setup/hold uncertainty. QVLD remains HIGH for the duration of each valid 36-bit word in the four-word burst and transitions synchronously with echo clock edges.