Renesas 72V251L15PFGI

Overview

72V251L15PFGI from Integrated Device Technology is a 3.3 V CMOS Synchronous FIFO memory with 8,192 × 9-bit depth, 10 ns read/write cycle time, dual-clock operation support (RCLK/WCLK), and programmable Almost-Empty/Almost-Full flags. It serves as a high-speed data buffer in interprocessor communication and graphics subsystems requiring deterministic latency and zero fall-through time architecture.

For engineers reviewing the 72V251L15PFGI datasheet, 72V251L15PFGI pinout, 72V251L15PFGI application, or 72V251L15PFGI equivalent, key selection criteria include industrial temperature range (–40°C to +85°C), 5V-tolerant inputs, TQFP-32 package, and configurable flag offset loading via WEN2/LD pin - all critical for legacy industrial control and telecom interface designs.

Technical Context

The 72V251L15PFGI implements a dual-ported, clocked FIFO architecture with independent read and write pointers synchronized to RCLK and WCLK respectively. Its fixed EF/FF flags and programmable PAE/PAF flags operate with precise clock-domain alignment: EF/PAE are RCLK-synchronized, FF/PAF are WCLK-synchronized, enabling robust cross-clock-domain status monitoring.

Flag offset configuration uses a 4-cycle state machine initiated by asserting WEN2/LD low at reset, loading 8-bit LSB/MSB registers for Empty and Full offsets. Default offsets are Empty+7 and Full−7, supporting immediate deployment without register programming in basic buffering applications.

Key Specifications

Pinout & Package

72V251L15PFGI is packaged in a 32-pin plastic Thin Quad FlatPack (TQFP), order code PFG, with 0.8 mm lead pitch and exposed thermal pad (non-electrical). Pin 1 marked by index notch; pin numbering follows standard counter-clockwise convention from top-left corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT72V251L15JGI, the 72V251L15PFGI offers superior thermal performance and smaller footprint in automated SMT lines; compared with ICS72V251L15PFGI, it represents the original IDT-branded version with identical silicon and qualification history.

Availability

72V251L15PFGI is available at Aetrix Electronics and suitable for industrial automation, telecom infrastructure, and embedded graphics applications requiring stable component supply and long-term lifecycle support.

Supply support for 72V251L15PFGI 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

Integrated Device Technology, Inc. (IDT) was a fabless semiconductor company specializing in timing, memory interface, and RF solutions before its acquisition by Renesas Electronics in 2019.

The IDT72V2xx family was designed specifically for high-reliability data buffering in cross-clock-domain systems, targeting graphics, networking, and industrial control applications where deterministic latency and flag-based flow control are essential.

FAQ

What is the memory organization of the 72V251L15PFGI?

The 72V251L15PFGI features an 8,192 × 9-bit synchronous FIFO memory array, providing 73,728 bits of total storage. This organization supports 9-bit parallel data paths commonly used in legacy graphics controllers and industrial serial protocols. Each word is accessed atomically, and the device does not support byte-level addressing or partial-word writes.

Does the 72V251L15PFGI support dual-clock operation?

Yes, the 72V251L15PFGI fully supports dual-clock operation with independent RCLK and WCLK inputs. Read operations synchronize to RCLK edges, write operations to WCLK edges, and status flags EF/PAE align to RCLK while FF/PAF align to WCLK - enabling robust asynchronous data transfer between unrelated clock domains in the 72V251L15PFGI.

How are the programmable Almost-Empty and Almost-Full flags configured in the 72V251L15PFGI?

The 72V251L15PFGI loads PAE/PAF offsets via a 4-cycle sequence using WEN2/LD, WEN1, and WCLK. On reset with WEN2/LD held LOW, four consecutive WCLK rising edges write LSB/MSB values to Empty and Full offset registers. Default values are 007H (7 decimal), yielding Empty+7 and Full−7 thresholds - a behavior confirmed in the 72V251L15PFGI datasheet Figure 3 and Table 1.

Is the 72V251L15PFGI pin-compatible with earlier IDT72251 devices?

No, the 72V251L15PFGI is not pin-compatible with the 5 V IDT72251. While functional behavior and pin functions match, the 72V251L15PFGI operates at 3.3 V and includes 5 V-tolerant inputs - requiring updated power delivery and signal integrity design. The pinout is identical, but voltage domain assumptions differ, making direct substitution unsafe without system-level validation of the 72V251L15PFGI.

What is the meaning of "L15" in the 72V251L15PFGI part number?

The "L15" suffix in 72V251L15PFGI denotes the 15 ns clock cycle time speed grade. This corresponds to a maximum clock frequency of 66.7 MHz and guarantees tCLK = 15 ns, tA ≤ 10 ns, and tWFF/tREF ≤ 15 ns under industrial temperature conditions - a specification explicitly defined in the AC Electrical Characteristics table of the 72V251L15PFGI datasheet.