Cypress Semiconductor Corp CY7C1643KV18-450BZC

Overview

CY7C1643KV18 from Cypress Semiconductor is a 144-Mbit QDR® II+ SRAM with 8 M × 18 organization, 450 MHz clock frequency, 2.0-cycle read latency, and separate read/write DDR ports delivering 900 MT/s effective data rate. It operates at 1.8 V core and 1.4–1.8 V I/O supply, housed in a 165-ball FBGA (15 × 17 × 1.4 mm), and targets high-bandwidth packet buffering in network switches and routers.

For engineers reviewing the CY7C1643KV18 datasheet, CY7C1643KV18 pinout, CY7C1643KV18 application, or CY7C1643KV18 equivalent, key selection criteria include its four-word burst architecture, echo clock (CQ/CQ) timing support, QVLD data-valid signaling, DOFF-configurable PLL mode, and HSTL-compatible 18-bit bidirectional I/O interface.

Technical Context

The CY7C1643KV18 implements a synchronous pipelined QDR II+ architecture with physically independent read and write ports-each using DDR interfaces synchronized to complementary K/K clocks. Address latching occurs on alternating rising edges of K/K, enabling concurrent read and write transactions without bus turnaround.

It integrates an internal PLL for precise data placement, supports programmable output impedance via ZQ calibration, and provides byte-write select (BWS0/BWS1) for granular 9-bit writes. The device delivers full data coherency and operates in either 2.0-cycle latency (DOFF = HIGH) or QDR I–compatible 1-cycle latency (DOFF = LOW).

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.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT72T36120L10BG and IS61WV102418BLL-15BLI, the CY7C1643KV18 uniquely balances 450 MHz DDR performance, flexible 1.4–1.8 V I/O, ZQ-calibrated outputs, and hardware-selectable latency-making it optimal for scalable, thermally constrained telecom and networking platforms.

Availability

CY7C1643KV18 is available at Aetrix Electronics and suitable for network switch buffering, high-speed test instrumentation, and telecom baseband processing requiring stable component supply, long-lifecycle support, and guaranteed Pb-free compliance.

Supply support for CY7C1643KV18 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 fabless semiconductor company specializing in high-performance memory, microcontrollers, and connectivity solutions for industrial, automotive, and communications markets.

The CY7C1643KV18 belongs to Cypress's QDR II+ SRAM product line, engineered specifically for deterministic, low-latency, high-throughput memory interfacing in packet-forwarding and real-time signal processing systems.

FAQ

What is the function of the DOFF pin on CY7C1643KV18?

The DOFF (PLL Disable) pin is an active-low control that disables the internal phase-locked loop. When tied LOW, the device reverts to QDR I timing with 1-cycle read latency and maximum 167 MHz operation. When HIGH (or pulled up), it enables full QDR II+ mode at up to 450 MHz with 2.0-cycle latency. This pin allows hardware-mode selection without firmware intervention.

How does the ZQ pin affect output drive strength?

The ZQ pin connects to an external resistor (RQ) to ground, enabling on-die calibration of CQ, CQ, and Q[17:0] output drivers to 0.2 × RQ impedance. This eliminates need for discrete series termination resistors and adapts drive strength to PCB trace impedance. Connecting ZQ directly to VDDQ sets minimum drive strength; floating or grounding ZQ is prohibited.

Can CY7C1643KV18 perform simultaneous read and write to the same address?

Yes-due to physically separate read and write ports and independent address latching on K/K rising edges, the CY7C1643KV18 supports true concurrent read and write operations to identical or overlapping addresses. Data coherency is maintained: a read returns the most recently written value, even if the write is still in progress within the pipeline.

What is the role of QVLD in system timing design?

QVLD is a synchronous, edge-aligned output that pulses high exactly when valid data appears on Q[17:0]. It is timed to align with CQ/CQ edges, providing a clean, jitter-tolerant strobe for capturing DDR output data. Unlike relying solely on clock edges, QVLD decouples data validity from clock skew-critical for robust setup/hold margin in high-speed FPGA or ASIC interfaces.