Infineon Technologies CY7C1570KV18-400BZXI

Overview

CY7C1570KV18 from Cypress Semiconductor is a 72-Mbit synchronous pipelined SRAM with DDR II+ architecture, configured as 2M × 36 (72-bit wide data bus), operating at 400 MHz with 2.5-cycle read latency and 1.8 V core / 1.4–1.8 V I/O supply. It uses dual input clocks (K/K̄) and echo clocks (CQ/CQ̄) for precise DDR timing and supports byte-selectable writes via BWS[3:0]. It is deployed in high-bandwidth networking line cards requiring deterministic low-latency memory access.

For engineers reviewing the CY7C1570KV18 datasheet, CY7C1570KV18 pinout, CY7C1570KV18 application, or CY7C1570KV18 equivalent, key selection criteria include DDR II+ burst timing compliance, HSTL I/O compatibility, QVLD-synchronized data validity, and PLL-enabled 2.5-cycle latency mode versus DOFF-activated DDR I fallback.

Technical Context

The CY7C1570KV18 implements a synchronous, pipelined two-word burst architecture where each read/write initiates on the rising edge of K, with address latched on alternate K edges and data transferred on both K and K̄ edges. Its internal organization comprises two 1M × 36 arrays, enabling concurrent access management across dual banks.

It integrates a phase-locked loop (PLL) for accurate data placement relative to echo clocks CQ/CQ̄, and includes JTAG 1149.1 boundary scan support, ZQ impedance calibration, and programmable DOFF control to switch between DDR II+ (2.5-cycle latency) and DDR I (1-cycle latency) operation modes.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with AS7C362000B-400BIN and IS61WV204836BLL-400BLI, the CY7C1570KV18 uniquely delivers PLL-controlled 2.5-cycle latency, QVLD-synchronized output validity, and dual-voltage HSTL I/O - making it optimal for new designs demanding timing predictability and signal integrity at 1100 MT/s.

Availability

CY7C1570KV18 is available at Aetrix Electronics and suitable for telecom line cards, high-speed packet buffers, industrial real-time controllers, and ATE pattern memory systems requiring stable component supply across extended product lifecycles.

Supply support for CY7C1570KV18 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.

The CY7C1570KV18 belongs to Cypress's QDR II+ SRAM product line, designed specifically for bandwidth-constrained, low-jitter applications in networking infrastructure and real-time embedded systems requiring deterministic DDR timing and robust signal integrity.

FAQ

What is the function of the DOFF pin on CY7C1570KV18?

The DOFF (PLL Turn Off) pin is an active-low control that disables the internal PLL when asserted LOW. In this state, the device operates in DDR I mode with 1-cycle read latency and a maximum frequency of 167 MHz. When DOFF is HIGH, the PLL is enabled, allowing full DDR II+ operation at up to 400 MHz with 2.5-cycle latency. The pin must be pulled up via ≤10 kΩ resistor for normal operation.

How does the ZQ pin affect signal integrity?

The ZQ pin connects to an external resistor to ground (typically 240 Ω) to calibrate the output driver impedance of DQ[35:0], CQ, and CQ̄ pins to 0.2 × RQ (≈48 Ω). This ensures matched 50 Ω trace termination, minimizing reflections and maintaining signal eye integrity at 1100 MT/s. Leaving ZQ unconnected or tying it to GND violates specification and degrades timing margins.

Can CY7C1570KV18 be depth-expanded with other SRAMs?

Yes - the device supports depth expansion using LD and R/W signals to coordinate multi-chip access. During deselection, outputs tristate automatically on the next K̄ rising edge, eliminating bus contention without external logic. Echo clocks (CQ/CQ̄) remain synchronized across devices when driven from a common K source, preserving timing alignment across expanded banks.

Is JTAG boundary scan supported in all operating modes?

Yes - IEEE 1149.1 JTAG functionality remains fully operational regardless of DOFF state or latency mode. TAP controller, instruction register, and boundary scan chain operate independently of the PLL and memory core timing, enabling in-system test and debug even during DDR I fallback or power-up sequences.