Infineon Technologies CY7C144AV-25AC

CY7C144AV-25AC Infineon Technologies SRAM IC Product Summary

The CY7C144AV-25AC is a high-speed, low-power dual-port static RAM introduced by Infineon Technologies, originally developed by Cypress Semiconductor. With a total capacity of 64Kbit organized as 8K × 8 words, it employs true dual-port architecture, enabling two independent processors or controllers to concurrently access the same memory space for parallel data exchange, buffering, and resource management. Housed in a compact 64-pin thin quad flat pack (TQFP), the CY7C144AV-25AC is tailored for demanding telecom, networking, and multiprocessing systems requiring both rapid data access (25 ns) and robust control over resource sharing. The device operates at a nominal 3.3 V supply, ensuring compatibility with modern CMOS logic and optimized power consumption.

Main Attributes of CY7C144AV-25AC Dual-Port SRAM

Engineered around a 0.35-micron CMOS process, the CY7C144AV-25AC delivers several features central to advanced system integration:

True dual-ported memory cells allow simultaneous access from both ports, including to the same address.

Fully asynchronous operation enables high system flexibility, eliminating need for global clocks between controlling entities.

Fast access time of 25 ns, supporting high-throughput requirements.

Low active current consumption (typical $I_{CC}$ = 115 mA) and minimal standby current ($I_{SB3}$ ≈ 10 μA) to facilitate energy-sensitive applications.

Expandable word width by employing Master/Slave chip select mechanisms—multiple devices may be configured for wider bus architectures.

On-chip arbitration logic effectively resolves port contention when simultaneous operations occur.

Dedicated semaphore circuitry (eight semaphores per device) supports hardware-based handshaking and mutual exclusion.

Built-in interrupt (INT) flags for inter-port communication and mailbox/message passing.

Master/Slave selection pin (M/S) for simple system expansion or cascading.

Available in Pb-free packages suitable for environmentally conscious production lines.

CY7C144AV-25AC Pinout Diagram and Signal Descriptions

In its 64-pin TQFP package, the CY7C144AV-25AC provides the following key signal categories:

Data I/O (I/O$_{0}$–I/O$_{7}$): Parallel 8-bit bus per port.

Address Inputs (A$_{0}$–A$_{12}$): 13 lines for 8K memory addressing (CY7C144AV); for 16K variants (CY7C006AV), A$_{0}$–A$_{13}$.

Control Signals: Chip Enable (CE), Output Enable (OE), Read/Write (R/W) for each port, enabling independent data flow.

BUSY: Signals port contention status, output in Master mode, input in Slave mode.

INT: Interrupt flag per port for mailbox operations and system-level notifications.

SEM: Semaphore pin to control access to shared resource flags.

Master/Slave (M/S) Selector: Dictates device arbitration role in multi-device configurations.

Detailed pin diagrams are provided within the documentation to facilitate schematic and PCB development.

CY7C144AV-25AC System Architecture and Operational Design

At the heart of the CY7C144AV-25AC is an array of dual-port RAM cells interfaced through separate address and control buses. Each port can operate independently, performing asynchronous read and write cycles without clock coordination. Arbitration logic automatically detects and resolves access collisions, while integrated mailbox and semaphore hardware support complex multiprocessor interactions such as mutual exclusion, handshaking, and resource allocation.

The design explicitly supports multi-device expansion. Using the Master/Slave pin, engineers can cascade devices to achieve wider data buses (e.g., 16-bit or more) with seamless arbitration and BUSY line connectivity.

CY7C144AV-25AC Memory Actions Reading, Writing, and Interrupt Handling

The CY7C144AV-25AC supports standard asynchronous read and write operations per port, controlled by OE, CE, and R/W pins:

Write Operation: Data must be valid for a defined setup time before the rising edge of R/W. Writes may be initiated via R/W or CE signal transitions.

Read Operation: Asserting both OE and CE triggers a memory read, with built-in flow-through delay in case of simultaneous writes to/from opposite ports.

Interrupt Operations: Highest memory locations are designated mailboxes. Writing data into the opposing port’s mailbox flags an interrupt, reset upon read. This mechanism is ideal for user-defined message passing between processors.

Arbitration Strategies, Busy Status Logic, and Master/Slave Configurations in CY7C144AV-25AC

Robust arbitration logic is a signature strength of the CY7C144AV-25AC. If a contention arises—both ports attempt to access the same location within the defined address-valid window—BUSY is asserted. The outcome depends on which side’s request was first; otherwise, the system will arbitrarily assign access if timing constraints ($t_{PS}$) are violated. For multi-device expansion, the Master device’s BUSY output connects to the Slave input, and write operations cascade after BUSY settles, maintaining consistent memory access integrity.

Semaphore Functions and Shared Resource Control in CY7C144AV-25AC

Eight integrated semaphore latches serve as hardware tokens, tightly controlling access to shared resources such as system buffers or peripherals. Each latch is accessed via the SEM pin and a three-bit address offset. Writing a zero requests ownership; a successful read-back of zero grants access, while one indicates the resource is busy (owned by the other port). Semaphore status changes are atomic when ports access them within specified timing ($t_{SPS}$), thus reliably preventing race conditions in complex multiprocessing environments.

Electrical Specs and Environmental Specifications for CY7C144AV-25AC

The device is robustly rated for industrial applications:

Supply Voltage Range: 3.0 V – 3.6 V

Storage Temperature: –65 °C to +150 °C

Operating Ambient: –55 °C to +125 °C

Input and Output Voltage: from –0.5 V to $V_{CC}$ + 0.5 V

Latch-up and ESD Immunity: Exceeds 200 mA and 2 kV, respectively

These specifications ensure reliable operation in a variety of embedded and industrial designs.

CY7C144AV-25AC Timing Performance, Switching Details, and Data Preservation

Engineers can expect high-speed performance with cycle times as low as 25 ns and minimal propagation delays. AC load diagrams and switching waveforms are included for validation and timing analysis. The CY7C144AV-25AC supports battery-backed data retention; CE must remain HIGH for guaranteed data stability, and power-on operation resumes after $t_{RC}$ once supply voltage reaches nominal minimum.

CY7C144AV-25AC Package Information and Physical Dimensions

The CY7C144AV-25AC is housed in a 64-pin Thin Quad Flat Pack (TQFP), with a 14 × 14 mm outline suitable for high-density assemblies. Proper PCB grounding and signal routing are critical for optimal performance at high data rates.

Alternative or Replacement Parts for CY7C144AV-25AC

For applications with expanded memory requirements, the CY7C006AV offers a 16K × 8 configuration with identical dual-port architecture, signal definitions, and functional capabilities, enabling direct substitution or modular system scaling. In designs standardized on Infineon or legacy Cypress peripherals, both CY7C144AV and CY7C006AV may be considered cross-compatible from the perspective of packaging and control logic, differing mainly in memory density.

Conclusion

: CY7C144AV-25AC in Advanced System-Level Designs

The CY7C144AV-25AC from Infineon Technologies presents system and component designers with a versatile, high-speed, dual-port asynchronous SRAM ideal for applications demanding concurrent data access, hardware-level arbitration, and reliable resource fencing. Its comprehensive signal interface, internal semaphore logic, and robust environmental ratings make it an optimal selection for communications, multiprocessing control, graphics, and industrial automation systems. The device’s scalability—through master/slave modes and its compatibility with higher-density models—ensures flexibility as design requirements evolve, highlighting the CY7C144AV-25AC as a long-term solution in high-performance, parallel access memory architectures.