Infineon Technologies CY7C12681KV18-400BZXC

Overview

CY7C12681KV18 from Cypress Semiconductor is a 36-Mbit DDR II+ SRAM with 2 M × 18 organization, 550 MHz max clock frequency, 2.5-cycle read latency, and HSTL I/O interface operating at VDDQ = 1.4–1.8 V. It delivers 1100 MT/s data throughput via double-data-rate transfers synchronized to K/K clocks and supports echo-clock–assisted data capture in high-speed networking and packet buffering systems.

For engineers reviewing the CY7C12681KV18 datasheet, CY7C12681KV18 pinout, CY7C12681KV18 application, or CY7C12681KV18 equivalent, this device is selected for synchronous burst memory subsystems requiring precise timing alignment, low-latency pipelined reads, and impedance-matched DDR signaling in FPGA-attached buffer designs.

Technical Context

This SRAM implements a synchronous pipelined architecture with dual-edge–referenced DDR II+ interface: address and control signals latch on alternating rising edges of K and K, while write data registers on both K and K edges and read data drives on both edges. The internal 2-word burst mode reduces address bus toggling frequency by half relative to data rate.

It integrates an on-chip PLL for accurate data placement, echo clocks (CQ/CQ) aligned to output data edges, and QVLD to indicate valid data windows. DOFF pin selects between 2.5-cycle (DOFF = HIGH) and 1-cycle (DOFF = LOW) read latency modes - enabling compatibility with both DDR II+ and legacy DDR I timing protocols.

Key Specifications

Pinout & Package

Package: 165-ball Fine-Pitch Ball Grid Array (FBGA), 13 mm × 15 mm × 1.4 mm body, 0.8 mm ball pitch, JEDEC MO-270AC compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C12681KV18-333BZXC, the -400BZXC variant provides 20% higher bandwidth and 12% higher current draw; versus AS7C3256A-15JCIN, it enables full DDR timing compliance and eliminates asynchronous setup/hold constraints but requires precise clock distribution.

Availability

CY7C12681KV18-400BZXC is available at Aetrix Electronics and suitable for high-speed packet buffering, FPGA-based protocol acceleration, telecom baseband processing, and industrial real-time control applications requiring stable component supply across multi-year production cycles.

Supply support for CY7C12681KV18-400BZXC 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 demanding embedded and communications systems.

This device belongs to the DDR II+ SRAM product line, engineered specifically for deterministic, low-jitter, burst-mode memory interfacing in FPGA- and ASIC-based high-speed data path applications.

FAQ

What is the function of the DOFF pin on CY7C12681KV18-400BZXC?

The DOFF (Data-Off) pin selects read latency mode: when asserted HIGH, it enables 2.5-cycle read latency for DDR II+ operation; when LOW, it configures the device for 1-cycle latency compatible with DDR I timing. This pin is sampled synchronously on the rising edge of K and remains latched until next reset or power cycle.

Can CY7C12681KV18-400BZXC operate with VDDQ = 1.5 V?

Yes - the device supports VDDQ from 1.4 V to 1.8 V, including 1.5 V nominal. At 1.5 V, HSTL-18 output drivers maintain specified VOH/VOL levels and AC timing parameters per datasheet Table 22, provided VDD remains at 1.8 V ± 0.1 V and temperature stays within –40 °C to +85 °C.

How does the ZQ pin affect signal integrity?

ZQ connects to a 240 Ω resistor to ground and calibrates internal output driver impedance to 60 Ω (0.2 × 240 Ω), matching standard PCB trace impedances. This calibration occurs at power-up and can be retriggered via JTAG, ensuring consistent edge rates and reduced reflections across voltage and temperature variations.

Is the 165-ball FBGA package lead-free?

Yes - the -400BZXC suffix denotes a Pb-free, RoHS-compliant 165-ball FBGA package. Cypress confirms this variant uses matte tin surface finish and meets JEDEC J-STD-020 moisture sensitivity level 3 (MSL3), requiring bake condition prior to reflow if exposed beyond floor life.