Cypress Semiconductor Corp CY7C1550KV18-450BZXC

Overview

CY7C1550KV18-450BZXC from Cypress Semiconductor is a 72-Mbit (2M × 36) DDR II+ synchronous SRAM with 2.0-cycle read latency, 450 MHz clock operation, and double-data-rate interface delivering 900 MT/s effective bandwidth. It features echo clocks (CQ/CQ), QVLD data-valid indicator, and programmable impedance matching via ZQ pin. Used in high-speed packet buffering for network switches and telecom line cards where deterministic low-latency burst reads are critical.

For engineers reviewing the CY7C1550KV18-450BZXC datasheet, CY7C1550KV18-450BZXC pinout, CY7C1550KV18-450BZXC application, or CY7C1550KV18-450BZXC equivalent, key selection criteria include DDR II+ timing compliance, 2M × 36 organization, 1.8 V core / 1.4–1.8 V I/O supply support, HSTL-compatible interfaces, and FBGA-165 package compatibility with high-density PCB layouts.

Technical Context

This SRAM implements a synchronous pipelined architecture with dual input clocks (K/K) driving all address, control, and data registers on rising edges. Read data is output on both K and K edges with precise alignment to echo clocks CQ/CQ, eliminating system-level skew compensation.

The device supports two operational modes: DDR II+ mode (DOFF = HIGH) with 2.0-cycle latency at up to 450 MHz, and DDR I mode (DOFF = LOW) with 1-cycle latency up to 167 MHz. Internal self-timed write circuitry ensures reliable synchronous writes without external timing constraints.

Key Specifications

Pinout & Package

Package: 165-ball fine-pitch ball grid array (FBGA), 13 mm × 15 mm × 1.4 mm body, RoHS-compliant, 0.8 mm ball pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C3256A-15JCIN and IS61WV102418BLL-10BLI, CY7C1550KV18-450BZXC delivers 9× higher effective bandwidth, deterministic DDR timing via echo clocks, and on-die impedance tuning - making it uniquely suited for modern high-speed packet and signal processing pipelines.

Availability

CY7C1550KV18-450BZXC is available at Aetrix Electronics and suitable for network packet buffering, telecom line card memory, high-speed test equipment memory, and radar signal processing buffer applications requiring stable component supply, long-term lifecycle support, and guaranteed FBGA-165 sourcing.

Supply support for CY7C1550KV18-450BZXC 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.

CY7C1550KV18 belongs to the QDR II+ SRAM product line, engineered specifically for deterministic, low-latency, high-bandwidth memory interfacing in networking and telecom infrastructure where DDR timing precision and signal integrity are mission-critical.

FAQ

What is the function of the DOFF pin on CY7C1550KV18-450BZXC?

The DOFF (PLL Turn Off) pin is an active-low control that disables the internal phase-locked loop. When asserted LOW, the device operates in DDR I mode with 1-cycle read latency and a maximum clock frequency of 167 MHz. When held HIGH (typically via 10 kΩ pull-up), it enables DDR II+ mode with 2.0-cycle latency and 450 MHz operation. This pin allows hardware-selectable timing modes for controller compatibility.

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

The ZQ pin connects to an external resistor to ground to calibrate the output driver impedance of DQ[35:0], CQ, and CQ pins to 0.2 × RQ. This on-die termination eliminates the need for discrete series or parallel termination resistors, reduces PCB routing complexity, and maintains consistent signal rise/fall times across voltage and temperature variations - directly improving eye diagram margin at 450 MHz.

Can CY7C1550KV18-450BZXC be used in place of CY7C1548KV18-450BZXC?

No - they are not pin-compatible or functionally interchangeable. CY7C1550KV18 is organized as 2M × 36 (36-bit data bus), while CY7C1548KV18 is 4M × 18 (18-bit data bus). Their FBGA-165 pinouts differ significantly: CY7C1550KV18 uses BWS[3:0] and DQ[35:0], whereas CY7C1548KV18 uses BWS[1:0] and DQ[17:0]. Board layout and controller interface must be redesigned for substitution.

What is the role of QVLD in system-level timing design?

QVLD is a synchronous output that asserts coincident with the rising edges of CQ and CQ to indicate when DQ[35:0] carries valid read data. Unlike fixed-delay approaches, QVLD eliminates the need for static timing margins or programmable delay lines - enabling simpler, more robust data capture logic in FPGAs or ASICs, especially under voltage/temperature variation or clock jitter.