Cypress Semiconductor Corp CY7C1145KV18-400BZXC

Overview

CY7C1145KV18-400BZXC from Cypress Semiconductor is a 18-Mbit QDR® II+ SRAM with 512K × 36 organization, 2.0-cycle read latency, and 400 MHz clock operation (800 Mbps DDR data rate per port). It features separate synchronous read/write ports, echo clocks (CQ/CQ), QVLD data-valid indicator, and programmable output impedance via ZQ pin. Used in high-bandwidth packet buffering for network switches and routers.

For engineers reviewing the CY7C1145KV18-400BZXC datasheet, CY7C1145KV18-400BZXC pinout, CY7C1145KV18-400BZXC application, or CY7C1145KV18-400BZXC equivalent, key selection criteria include 400 MHz K/K clock support, 36-bit DDR I/O with HSTL compatibility, DOFF-controlled PLL mode switching, and 165-ball FBGA (13 × 15 mm) package constraints.

Technical Context

The CY7C1145KV18 implements QDR II+ architecture with fully independent read and write ports sharing one multiplexed address bus (A[16:0]), enabling concurrent transactions without bus turnaround. Each port uses double-data-rate interfaces synchronized to complementary K and K clocks, delivering four 36-bit words per access cycle.

Internal PLL enables precise 2.0-cycle read latency when DOFF = HIGH; disabling PLL via DOFF = LOW reverts device to QDR I timing (max 167 MHz). Echo clocks CQ/CQ align with K/K edges to simplify high-speed capture, while QVLD provides edge-aligned validity indication for all four burst words.

Key Specifications

Pinout & Package

Package: 165-ball Fine-Pitch Ball Grid Array (FBGA), 13 mm × 15 mm body, 1.4 mm height, RoHS-compliant Pb-free finish (BZXC suffix).

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 IS61WV102432BLL-10BLI, CY7C1145KV18-400BZXC delivers 2.8× higher effective bandwidth via DDR + burst, eliminates bus turnaround overhead, and provides deterministic 2-cycle latency - critical for real-time packet processing and telecom infrastructure.

Availability

CY7C1145KV18-400BZXC is available at Aetrix Electronics and suitable for network switches, telecom line cards, baseband processors, and high-speed test equipment requiring stable component supply and long-term obsolescence management.

Supply support for CY7C1145KV18-400BZXC 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) designs high-performance memory and programmable solutions for networking, automotive, and industrial applications.

The QDR® II+ SRAM product line targets high-speed packet buffering and deterministic latency applications in communications infrastructure, where concurrent read/write throughput and precise timing control are essential.

FAQ

What is the function of the DOFF pin on CY7C1145KV18-400BZXC?

The DOFF pin controls the internal PLL: when pulled HIGH (via 10 kΩ or lower pull-up), the device operates in QDR II+ mode with 2.0-cycle read latency and supports up to 400 MHz clocking. When pulled LOW, the PLL is disabled and the device reverts to QDR I timing, limiting maximum frequency to 167 MHz with 1-cycle latency. This pin must never be left floating or tied directly to ground.

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

The ZQ pin connects to an external resistor to ground (typically 100 Ω) to calibrate the output driver impedance of Q[35:0], CQ, and CQ pins to 0.2 × RQ (e.g., 20 Ω). This matches typical PCB trace impedances, reducing reflections and improving eye diagram margins. Leaving ZQ unconnected or tying it to VSS violates specification and degrades output waveform fidelity.

Can CY7C1145KV18-400BZXC perform concurrent read and write operations to the same memory location?

Yes - the device supports true concurrent read and write operations to the same address due to its physically separate read and write data paths and pipelined architecture. However, writing to an address currently being read may return stale data for that burst if the write completes after the read has latched the address but before data is driven out; coherency is maintained only for subsequent reads.

What is the role of BWS[3:0] in byte-level write control?

BWS[3:0] are active-low byte write select signals that mask individual 9-bit segments of the 36-bit D[35:0] bus: BWS0 covers D[8:0], BWS1 covers D[17:9], BWS2 covers D[26:18], and BWS3 covers D[35:27]. When a BWS bit is HIGH, the corresponding byte is ignored during write; when LOW, that byte is written. This enables partial-word updates without requiring read-modify-write sequences.