Infineon Technologies CY7C4245V-15ASXC

Overview

CY7C4245V-15ASXC from Cypress Semiconductor is a 4K × 18-bit, 3.3 V synchronous FIFO memory with 67 MHz operation (15 ns read/write cycle), 5 V-tolerant inputs, and programmable Almost Full/Almost Empty flags. It serves as a high-speed data buffer in asynchronous interface bridging between dissimilar clock domains, supporting depth/width expansion for system-level scalability.

For engineers reviewing the CY7C4245V-15ASXC datasheet, CY7C4245V-15ASXC pinout, CY7C4245V-15ASXC application, or CY7C4245V-15ASXC equivalent, key selection criteria include synchronous flag timing behavior, retransmit functionality for packet recovery, 18-bit bus width, 4K depth, and dual-clock operation with independent RCLK/WCLK control.

Technical Context

The CY7C4245V-15ASXC implements a dual-port SRAM-based FIFO architecture with separate read and write pointers, fully asynchronous read/write enable logic (REN/WEN), and synchronous status flags updated exclusively on RCLK (EF, PAE) or WCLK (FF, PAF) edges. Its programmable offset registers allow user-defined trigger thresholds for PAE/PAF flags via LD-controlled 12-bit writes.

Depth expansion uses WXO/RXO cascading with FL pin configuration (VSS for first device, VCC for others), while width expansion shares control signals and requires external ANDing of EF/FF flags. Retransmit (RT) resets the read pointer to the FIFO start without affecting write pointer or data integrity, enabling deterministic packet replay in communication protocols.

Key Specifications

Pinout & Package

64-pin STQFP (10 × 10 mm) and TQFP (14 × 14 mm) package options; CY7C4245V-15ASXC uses the 64-pin STQFP variant per ordering code suffix "SXC".

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar FIFO memory applications.

Compared with IDT72V2115L15PF and NB3N502M, CY7C4245V-15ASXC uniquely combines 4K depth, retransmit capability, programmable flag offsets, and robust depth/width expansion-making it optimal for deterministic, scalable buffering in protocol-aware embedded systems.

Availability

CY7C4245V-15ASXC is available at Aetrix Electronics and suitable for high-speed data acquisition, multiprocessor interfacing, communications protocol buffering, and video frame synchronization requiring stable component supply and long-term lifecycle support.

Supply support for CY7C4245V-15ASXC 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 logic solutions for industrial, automotive, and communications markets.

The CY7C42X5V family was engineered specifically for high-speed, low-latency data buffering in mixed-clock-domain systems-emphasizing reliability, expandability, and deterministic flag timing over generic memory performance.

FAQ

What is the function of the VCC/SMODE pin on CY7C4245V-15ASXC?

The VCC/SMODE pin configures the synchronization behavior of the Programmable Almost Empty (PAE) and Programmable Almost Full (PAF) flags. When tied to VSS (ground), PAE becomes synchronized to RCLK and PAF to WCLK-ensuring deterministic timing relative to read/write operations. When tied to VCC, both flags operate asynchronously, offering faster response at the cost of potential metastability in noisy environments.

How does the retransmit (RT) feature work in standalone mode?

In standalone mode, applying a HIGH pulse to the RT pin resets the internal read pointer to the first physical location of the FIFO, enabling immediate retransmission of all previously written data. During RT assertion, WCLK and RCLK must be disabled for tRTR (minimum 10 ns), after which reads resume from the beginning-preserving write pointer position and uncommitted data.

Can CY7C4245V-15ASXC be used in depth-expanded configurations with other CY7C42X5V variants?

Yes-CY7C4245V-15ASXC supports depth expansion with any CY7C42X5V device (e.g., CY7C4235V, CY7C4225V) using WXO/WXI and RXO/RXI pins. The FL pin must be configured as VSS for the first device and VCC for subsequent ones. All devices in the chain must share common RCLK/WCLK and control signals, and flag logic must be externally coordinated.

What is the default Almost Empty offset value for CY7C4245V-15ASXC?

The default Almost Empty offset value is 127 words. This means the PAE flag asserts when 127 or fewer words remain in the FIFO. The offset is stored in a 12-bit register and can be reprogrammed via the LD/WEN/WCLK sequence to values between 0 and 4095, allowing precise tuning of flow-control thresholds for specific system latency requirements.