Infineon Technologies CY7C1665KV18-550BZXC

Overview

CY7C1665KV18 from Cypress Semiconductor is a 4 M × 36, 144-Mbit QDR® II+ SRAM with separate read/write ports, 550-MHz clock operation (1100-MHz DDR data rate), 2.5-cycle read latency, and HSTL I/O compatible with 1.4–1.8-V VDDQ. It delivers full data coherency and supports concurrent read/write transactions in high-bandwidth networking buffers.

For engineers reviewing the CY7C1665KV18 datasheet, CY7C1665KV18 pinout, CY7C1665KV18 application, or CY7C1665KV18 equivalent, key selection criteria include its QDR II+ burst architecture, echo-clock–assisted timing capture, DOFF-configurable latency mode, and 165-ball FBGA package with ZQ impedance tuning.

Technical Context

The CY7C1665KV18 implements a synchronous pipelined QDR II+ architecture with independent read and write ports sharing a multiplexed 20-bit address bus. It uses dual input clocks (K/K) for DDR edge-aligned data transfers and echo clocks (CQ/CQ) to simplify high-speed data capture at 1100 MHz.

Its internal organization comprises four 1 M × 36 memory arrays; depth expansion is enabled via RPS/WPS and four byte-write selects (BWS[3:0]). The PLL ensures precise data placement, and DOFF pin toggles between 2.5-cycle QDR II+ mode (550 MHz) and 1-cycle QDR I mode (≤167 MHz).

Key Specifications

Pinout & Package

Package: 165-ball fine-pitch ball grid array (FBGA), 15 mm × 17 mm × 1.4 mm, Pb-free, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar QDR II+ SRAM applications.

Compared with IDT72T36150 and IS61WV102436B, CY7C1665KV18 uniquely combines 550-MHz QDR II+ performance with HSTL-15/18 compatibility, on-die impedance tuning, and echo-clock–assisted timing - making it optimal for new high-speed serial fabric designs requiring minimal external components and guaranteed coherency.

Availability

CY7C1665KV18 is available at Aetrix Electronics and suitable for 10G/25G Ethernet switching, 5G baseband processing, high-frequency trading accelerators, and PCIe Gen4 endpoint caching requiring stable component supply and long-term lifecycle assurance.

Supply support for CY7C1665KV18 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, PSoC programmable systems-on-chip, and USB/USB-C solutions.

The QDR® II+ SRAM product line was designed specifically for ultra-low-latency, high-throughput data-path buffering in networking, telecom, and financial infrastructure - prioritizing deterministic timing, concurrent access, and signal integrity at multi-GHz rates.

FAQ

What is the function of the DOFF pin on CY7C1665KV18?

The DOFF (PLL Disable) pin is an active-low control that disables the internal PLL. When pulled low, the device reverts to QDR I timing with 1-cycle read latency and maximum operating frequency reduced to 167 MHz. For full QDR II+ operation at 550 MHz with 2.5-cycle latency, DOFF must be held high via a ≤10-kΩ pull-up to VDDQ.

How does the ZQ pin affect signal integrity in high-speed designs?

The ZQ pin connects to an external resistor to ground (typically 240 Ω) to calibrate the output driver impedance of Q[35:0], CQ, and CQ pins to 0.2 × RQ (e.g., 48 Ω). This matches standard PCB trace impedances, reducing reflections and improving eye diagram margins without discrete series termination resistors.

Can CY7C1665KV18 operate with different supply voltages on VDD and VDDQ?

Yes - VDD is strictly 1.8 V ± 0.1 V for the core logic, while VDDQ may be independently set between 1.4 V and 1.8 V to match host interface voltage (e.g., HSTL-15 at 1.5 V or HSTL-18 at 1.8 V). This dual-supply flexibility enables interoperability with diverse FPGA I/O banks without level-shifting circuitry.

What is the purpose of the QVLD signal, and how is it timed relative to data?

QVLD is a synchronous output that asserts one cycle before the first valid data word appears on Q[35:0] in each read burst. It is edge-aligned with CQ and CQ, providing a clean, jitter-free strobe for capturing the full four-word burst - eliminating setup/hold uncertainty and enabling robust DDR sampling in FPGA logic without manual delay tuning.