Infineon Technologies CY7C1568KV18-450BZXI

Overview

CY7C1568KV18 from Cypress Semiconductor is a 72-Mbit (4M × 18) synchronous DDR II+ SRAM with two-word burst architecture, 2.5-cycle read latency at 450 MHz, HSTL I/O interface, and 165-ball FBGA (13 × 15 × 1.4 mm) package. It operates with core VDD = 1.8 V ± 0.1 V and I/O VDDQ = 1.4–1.8 V, and integrates echo clocks (CQ/CQ), QVLD data-valid indicator, and JTAG 1149.1 test port for high-speed memory subsystems in networking line cards.

For engineers reviewing the CY7C1568KV18 datasheet, CY7C1568KV18 pinout, CY7C1568KV18 application, or CY7C1568KV18 equivalent, this device supports precise DDR timing via dual K/K clocks, synchronous self-timed writes, programmable impedance matching via ZQ, and configurable latency (2.5-cycle DDR II+ or 1-cycle DDR I mode via DOFF pin).

Technical Context

The CY7C1568KV18 implements a pipelined synchronous SRAM core with DDR II+ architecture, using rising edges of complementary K and K clocks to latch addresses, register write data, and drive read data. All synchronous inputs (A, R/W, LD, BWS[1:0]) are registered on K's rising edge; data I/O (DQ[17:0]) is double-data-rate registered on both K and K edges.

It features an internal PLL for accurate data placement, echo clocks (CQ/CQ) synchronized to K for simplified high-speed data capture, and QVLD aligned to CQ/CQ edges to indicate valid output data. The DOFF pin selects between 2.5-cycle latency (DOFF = HIGH) and 1-cycle DDR I mode (DOFF = LOW), enabling interoperability across legacy and high-bandwidth systems.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C361024B-15JIN and IS61WV102418BLL-10BLI, the CY7C1568KV18 uniquely delivers 900 MT/s DDR throughput with integrated echo clocks and programmable latency-enabling timing-critical, high-density memory subsystems that neither alternative can support.

Availability

CY7C1568KV18 is available at Aetrix Electronics and suitable for high-speed network line cards, telecom baseband processing, and test equipment memory subsystems requiring stable component supply, long-term lifecycle assurance, and guaranteed Pb-free sourcing.

Supply support for CY7C1568KV18 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 demanding embedded and communications applications, with focus on signal integrity, timing precision, and system-level integration.

The CY7C1568KV18 belongs to Cypress's DDR II+ SRAM product line, engineered specifically for bandwidth-constrained, low-latency memory buffering in networking, telecom, and test instrumentation where traditional DRAM lacks determinism and async SRAM lacks speed.

FAQ

What is the function of the DOFF pin on CY7C1568KV18?

The DOFF pin is an active-LOW PLL disable control. When asserted LOW, it disables the internal PLL and forces the device into DDR I mode with 1-cycle read latency and maximum 167 MHz operation. When held HIGH (e.g., via 10 kΩ pull-up), the PLL remains active, enabling full DDR II+ operation at up to 450 MHz with 2.5-cycle latency. This pin provides hardware-selectable timing modes without firmware intervention.

How does the ZQ pin calibrate output impedance?

The ZQ pin connects to an external resistor (RQ) tied to ground, enabling on-die calibration of DQ and CQ output driver impedance to 0.2 × RQ. This compensates for process, voltage, and temperature variations, ensuring consistent signal integrity without discrete termination. Direct connection to VDDQ enables minimum-impedance mode; floating or grounding ZQ is prohibited and may damage the device.

Can CY7C1568KV18 be used without the PLL enabled?

Yes - asserting DOFF LOW disables the PLL and reconfigures the device as a DDR I SRAM with 1-cycle read latency and reduced maximum frequency (167 MHz). In this mode, timing parameters shift to match JEDEC DDR I specifications, and echo clocks (CQ/CQ) remain functional but derive from K without PLL multiplication. Full DDR II+ features like 2.5-cycle latency and 450 MHz operation require DOFF = HIGH.

What is the role of QVLD in system timing design?

QVLD is a synchronous output signal edge-aligned with CQ and CQ, indicating when DQ[17:0] carries valid read data. It eliminates the need for fixed delay chains or complex timing margin calculations at the receiver, allowing FPGA or ASIC logic to sample data reliably on the next CQ edge. Its guaranteed setup/hold relationship to DQ simplifies high-speed capture and reduces timing closure effort in multi-SRAM systems.