Infineon Technologies CY7C1645KV18-400BZXI

Overview

CY7C1645KV18 from Cypress Semiconductor is a 4-M × 36-bit, 144-Mbit QDR® II+ SRAM with 2.0-cycle read latency, 400 MHz clock operation (800 Mbps DDR per port), 1.8-V core supply, and 1.4–1.8-V I/O supply. It features separate read/write ports, echo clocks (CQ/CQ), QVLD data-valid indicator, and JTAG 1149.1 test access-designed for high-bandwidth packet buffering in network switches and routers.

For engineers reviewing the CY7C1645KV18 datasheet, CY7C1645KV18 pinout, CY7C1645KV18 application, or CY7C1645KV18 equivalent, key selection criteria include its 4-word burst architecture, synchronous self-timed writes, DOFF-configurable latency mode (QDR I vs. QDR II+), HSTL I/O compatibility, and 165-ball FBGA package footprint.

Technical Context

The CY7C1645KV18 implements a true dual-port QDR II+ architecture with independent read and write pipelines, enabling concurrent transactions without bus turnaround. Its 20-bit address bus accesses a 4-M × 36 memory array organized as four 1-M × 36 sub-arrays, with addresses latched on alternating edges of K/K clocks.

It integrates an internal PLL for precise data placement and uses echo clocks (CQ/CQ) aligned to output data for simplified high-speed capture. The DOFF pin selects between 2.0-cycle QDR II+ mode (up to 400 MHz) and 1-cycle QDR I mode (≤167 MHz), while ZQ enables programmable output impedance matching to system bus termination.

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 IDT72T36150 and IS61WV102432BLL, the CY7C1645KV18 delivers 2× higher density, 14% higher clock rate, integrated PLL timing control, and hardware-supported burst/echo/QVLD features essential for deterministic 100+ GbE packet processing.

Availability

CY7C1645KV18 is available at Aetrix Electronics and suitable for network switch fabric design, high-speed test instrumentation, telecom baseband subsystems, and AI accelerator memory subsystems requiring stable component supply across multi-year production cycles.

Supply support for CY7C1645KV18 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 applications demanding deterministic latency, concurrent dual-port access, and DDR bandwidth without bus turnaround - especially in infrastructure-grade communications equipment.

FAQ

What is the function of the DOFF pin on CY7C1645KV18?

The DOFF (PLL Disable) pin is an active-low control that disables the internal phase-locked loop. When tied LOW, the device operates in QDR I mode with 1-cycle read latency and a maximum clock frequency of 167 MHz. When HIGH, it enables QDR II+ mode with 2.0-cycle latency and up to 400 MHz operation. This pin must be pulled up via ≤10 kΩ resistor for normal QDR II+ use.

How does the ZQ pin affect output drive strength?

The ZQ pin connects to an external resistor (RQ) to ground, calibrating the output impedance of Q[35:0], CQ, and CQ to 0.2 × RQ. For example, a 50-Ω RQ yields 10-Ω driver impedance. Connecting ZQ directly to VDDQ enables minimum impedance mode. ZQ must never be left floating or tied to GND, as this disables impedance control and risks signal integrity failure.

Can CY7C1645KV18 perform simultaneous read and write operations?

Yes - the CY7C1645KV18 supports true concurrent read and write transactions due to physically separate read and write data paths, independent port selects (RPS/WPS), and shared but edge-multiplexed address bus. Each port operates on its own timing domain synchronized to K/K, enabling full-duplex memory access without arbitration or bus turnaround delays.

What is the role of QVLD in system timing design?

QVLD is a synchronous output pulse edge-aligned with CQ and CQ, indicating precisely when Q[35:0] carries valid burst data. Unlike simple clock alignment, QVLD accounts for internal propagation delays and guarantees data stability window - allowing downstream logic to sample Q[35:0] with relaxed setup/hold margins and eliminating need for complex strobe deskew circuits.