Infineon Technologies CY7C4245-10AXI

Overview

CY7C4245-10AXI from Cypress Semiconductor is a 4K × 18-bit synchronous FIFO memory with 100 MHz operation (10 ns read/write cycle), TTL-compatible I/O, and programmable Almost Full/Almost Empty flags. It supports independent read/write clocks, retransmit functionality, and depth/width expansion for buffering in high-speed data acquisition and multiprocessor interfaces.

For engineers reviewing the CY7C4245-10AXI datasheet, CY7C4245-10AXI pinout, CY7C4245-10AXI application, or CY7C4245-10AXI equivalent, key selection criteria include its 4K-depth 18-bit bus, synchronous flag timing control via VCC/SMODE, cascading capability using WXO/RXO/FL pins, and industrial-grade operation at −40°C to +85°C in 68-pin PLCC.

Technical Context

The CY7C4245-10AXI implements a dual-port SRAM-based FIFO architecture with separate WCLK/REN and RCLK/WEN control paths, enabling true asynchronous read/write operation. Its write pointer and read pointer operate independently, with EF synchronized to RCLK and FF synchronized to WCLK.

Flag behavior is configurable: PAE and PAF operate asynchronously when VCC/SMODE = VCC, or synchronously (to RCLK/WCLK respectively) when VCC/SMODE = VSS. Retransmit (RT) resets the read pointer to the first location, supporting packet retransmission without external logic.

Key Specifications

Pinout & Package

Package: 68-pin PLCC (10 × 10 mm body, 0.05 inch lead pitch). Center power/ground layout minimizes switching noise and improves signal integrity in mixed-signal systems.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT72V2105L10PF and NB3N502DR2G, the CY7C4245-10AXI uniquely combines 5 V TTL compatibility, hardware retransmit, programmable flags, and full expansion support-making it irreplaceable in legacy industrial and test equipment requiring robust, field-upgradeable buffering.

Availability

CY7C4245-10AXI is available at Aetrix Electronics and suitable for high-speed data acquisition, multiprocessor interconnect, communications protocol buffering, and legacy system interface adapter applications requiring stable component supply across extended temperature ranges.

Supply support for CY7C4245-10AXI 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 interface ICs for industrial, automotive, and communications infrastructure markets.

The CY7C42X5 family was engineered specifically for deterministic, low-latency data buffering in mixed-clock-domain systems-emphasizing flag predictability, expansion flexibility, and robustness in harsh operating conditions.

FAQ

What is the function of the VCC/SMODE pin on CY7C4245-10AXI?

The VCC/SMODE pin configures the timing behavior of the Programmable Almost Empty (PAE) and Programmable Almost Full (PAF) flags. When tied to VCC, PAE and PAF operate asynchronously; when tied to VSS, PAE becomes synchronized to RCLK and PAF to WCLK-ensuring deterministic flag assertion timing relative to respective clock domains.

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

In standalone mode, a HIGH pulse on the RT pin resets the internal read pointer to the first physical FIFO location. After RT deassertion, subsequent reads (with REN and OE active) output previously written data in sequence until the write pointer is reached-enabling hardware-accelerated packet replay without CPU overhead or external memory access.

Can multiple CY7C4245-10AXI devices be cascaded for greater depth?

Yes-up to 16 devices can be depth-expanded using WXO→WXI and RXO→RXI connections. The FL pin of the first device is grounded; all others connect to VCC. This daisy-chain configuration preserves full 100 MHz performance and maintains independent flag generation per device, scaling total capacity to 64K × 18 bits.

Is the CY7C4245-10AXI compatible with 3.3 V logic interfaces?

No-the CY7C4245-10AXI is strictly a 5 V TTL-compatible device. Its input thresholds and output drive levels conform to standard TTL specifications (V_IL ≤ 0.8 V, V_IH ≥ 2.0 V, V_OL ≤ 0.4 V, V_OH ≥ 2.4 V). Direct connection to 3.3 V logic requires level-shifting circuitry to prevent damage or unreliable operation.