Cypress Semiconductor Corp CY7C1320KV18-250BZC

Overview

CY7C1320KV18-250BZC from Cypress Semiconductor is a 18-Mbit synchronous DDR II SRAM configured as 512K × 36, operating at 250 MHz with 1.8 V core supply and HSTL I/O. It implements two-word burst reads/writes synchronized to dual K/K input clocks and outputs data on C/C with echo clocks CQ/CQ for precise high-speed capture. Used in network packet buffers and FPGA co-processor memory interfaces requiring low-latency, burst-access SRAM.

For engineers reviewing the CY7C1320KV18-250BZC datasheet, CY7C1320KV18-250BZC pinout, CY7C1320KV18-250BZC application, or CY7C1320KV18-250BZC equivalent, key selection criteria include DDR-II burst timing, 36-bit wide interface, DOFF-configurable 1-cycle vs. 1.5-cycle read latency, HSTL drive strength programmability via ZQ, and 165-ball FBGA (13 × 15 × 1.4 mm) mechanical compatibility.

Technical Context

This device uses a synchronous pipelined architecture with internal burst counter driven by A0, delivering two consecutive 36-bit words per access. All address, control, and write data inputs are registered on rising edges of complementary K/K clocks, enabling precise setup/hold timing at 250 MHz.

Read data is edge-aligned to complementary C/C output clocks, with echo clocks CQ/CQ phase-matched to C/C for receiver-side deskewing. The DOFF pin selects between DDR-I mode (1-cycle latency, R/W HIGH/LOW aligned to K) and DDR-II mode (1.5-cycle latency, staggered R/W sampling), while ZQ enables dynamic output impedance calibration to 0.2×RQ.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed burst SRAM applications.

Compared with AS7C331024B-25BIN and IS61WV102432BLL-10TLI, CY7C1320KV18-250BZC delivers 5.6× higher bandwidth via DDR-II burst and eliminates board-level timing closure challenges through echo clocks and programmable drive strength-critical for 10G+ systems.

Availability

CY7C1320KV18-250BZC is available at Aetrix Electronics and suitable for network packet buffering, FPGA co-processor caching, telecom line card memory, and industrial motion controller buffering requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CY7C1320KV18-250BZC 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.

CY7C1320KV18 belongs to Cypress's DDR II SRAM product line, designed specifically for high-throughput, low-latency memory subsystems in networking, test equipment, and FPGA-accelerated computing where deterministic burst access and signal integrity at 500 Mbps/pin are essential.

FAQ

What is the function of the DOFF pin on CY7C1320KV18-250BZC?

The DOFF (Data Output OFF) pin configures read latency mode: when tied LOW, the device operates in DDR-I mode with 1-cycle read latency; when tied HIGH, it enters DDR-II mode with 1.5-cycle latency. This selection affects controller timing constraints and setup/hold margins but does not alter burst depth, data width, or clocking architecture.

How does ZQ calibration work on this SRAM?

ZQ connects to an external precision resistor (typically 240 Ω) to ground, enabling on-die calibration of HSTL output drivers to achieve 50 Ω impedance matching. The device measures RQ and adjusts internal current sources so that DQ[35:0], CQ, and CQ output impedances equal 0.2 × RQ. Direct connection to VDDQ enables minimum impedance mode.

Can CY7C1320KV18-250BZC operate with only K clock (no K, C, or C)?

Yes-single-clock mode is supported: K serves as both input and output clock reference, with K, C, and C left unconnected or tied to VDD/VSS per datasheet guidelines. In this mode, data is latched and driven on K edges only, eliminating need for differential clock routing but reducing maximum achievable bandwidth and skew compensation capability.

What is the purpose of the BWS[3:0] pins in 36-bit configuration?

BWS[3:0] are active-low byte write select signals controlling four independent 9-bit lanes of the 36-bit data bus. BWS0–BWS3 correspond to D[8:0], D[17:9], D[26:18], and D[35:27], respectively. Asserting only selected BWS lines enables partial writes without read-modify-write cycles, preserving unselected byte lanes' contents.