Infineon Technologies CY7C1021BNV33L-15ZXC

Overview

CY7C1021BNV33L-15ZXC from Cypress Semiconductor is a 64K × 16-bit (1,048,576-bit) asynchronous CMOS static RAM operating at 3.3 V with 15 ns access time, low active power (576 mW max), and automatic CE-controlled power-down. It supports independent byte-wide write enable via BHE/BLE pins and is used in embedded controllers, network packet buffers, and industrial PLC data logging where deterministic timing and low standby current are critical.

For engineers reviewing the CY7C1021BNV33L-15ZXC datasheet, CY7C1021BNV33L-15ZXC pinout, CY7C1021BNV33L-15ZXC application, or CY7C1021BNV33L-15ZXC equivalent, this page provides verified package mapping (44-pin TSOP II), byte-select timing behavior, tAA/tRC/tPD values, VCC retention voltage (2.0 V), and real-world SRAM interface constraints for PCB layout and power budgeting.

Technical Context

This SRAM implements a full asynchronous interface with separate Byte High Enable (BHE) and Byte Low Enable (BLE) controls, enabling true 8-bit sub-word writes without read-modify-write cycles. Its dual-byte architecture allows concurrent access to upper and lower data bytes under independent address control.

The device uses standard TTL-compatible input thresholds (VIH = 2.2 V, VIL = 0.8 V) and delivers CMOS-level outputs (VOH ≥ 2.4 V, VOL ≤ 0.4 V) at 3.3 V supply. Power-down activation occurs automatically when CE is deasserted, reducing ICC to 500 µA (L version) with no external control required.

Key Specifications

Pinout & Package

Package: 44-pin TSOP Type II (10.16 mm × 18.42 mm, 0.8 mm pitch), RoHS-compliant, surface-mount.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar asynchronous SRAM applications.

Compared with IS61LV1024-15KLI and MC1021V33L-15Z, CY7C1021BNV33L-15ZXC uniquely delivers byte-select write capability, 500 µA standby, and 2.0 V data retention-making it the only choice for energy-constrained, safety-aware, or partial-write-intensive designs.

Availability

CY7C1021BNV33L-15ZXC is available at Aetrix Electronics and suitable for industrial PLC data buffering, network packet memory, medical imaging frame stores, and avionics display controller caches requiring stable component supply across extended product lifecycles.

Supply support for CY7C1021BNV33L-15ZXC 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-reliability memory and programmable logic solutions for industrial, automotive, and communications systems.

The CY7C1021BNV series targets deterministic, low-power embedded memory applications requiring asynchronous access, byte granularity, and robust data retention-especially where firmware simplicity and thermal efficiency are prioritized over density scaling.

FAQ

What is the minimum VCC required to retain data in CY7C1021BNV33L-15ZXC?

The device guarantees data retention down to VCC = 2.0 V, as specified in the Data Retention Characteristics table. At this voltage, ICCDR is limited to 100 µA maximum, enabling multi-year retention on coin-cell backup. Operation below 2.0 V risks bit corruption; no functional operation is supported below 3.0 V.

Can CY7C1021BNV33L-15ZXC perform a write to only the upper byte without affecting the lower byte?

Yes. When BHE = LOW and BLE = HIGH, only I/O9–I/O16 are written; I/O1–I/O8 remain unchanged and high-impedance. This is confirmed by the Truth Table (Page 8) and Functional Description, which explicitly define independent byte write paths with no internal coupling or dependency.

Does the 15 ns access time apply to both read and write cycles?

No. The 15 ns value applies specifically to read access time (tAA and tACE). Write cycle time (tWC) is also 15 ns, but write setup/hold parameters differ: tAW = 10 ns, tSD = 8 ns, and tPWE = 10 ns. These values are distinct and must be met independently per the Switching Characteristics table (Page 4).

Is the 44-pin TSOP II package of CY7C1021BNV33L-15ZXC RoHS-compliant?

Yes. The "ZXC" suffix denotes lead-free (Pb-free) construction per the Ordering Information table (Page 8), and the package diagram references "51-85087 44-Lead TSOP Type II (Pb-free)". Cypress documentation confirms full compliance with EU RoHS Directive 2011/65/EU and JEDEC J-STD-609A Class 3 marking.