Diodes Incorporated PI74FCT2541ATQ

Overview

PI74FCT2541ATQ from Pericom Semiconductor is a non-inverting octal buffer/line driver with 3-state outputs, designed for high-speed bus driving in 5V TTL-compatible systems. It features built-in 25Ω series output resistors, TTL-level inputs/outputs, industrial temperature range (–40°C to +85°C), and operates at propagation delays as low as 1.5 ns (typ) / 3.8 ns (max) at CL = 50 pF. It is used in address/data bus drivers for memory subsystems and system clock distribution.

For engineers reviewing the PI74FCT2541ATQ datasheet, PI74FCT2541ATQ pinout, PI74FCT2541ATQ application, or PI74FCT2541ATQ equivalent, key selection criteria include output drive strength (64 mA sink), input hysteresis (200 mV), quiescent current (≤500 µA), and TSSOP-20 package compatibility with dense PCB layouts requiring input/output physical separation.

Technical Context

The PI74FCT2541ATQ implements dual 4-bit non-inverting buffers with independent 3-state control: OEA enables outputs OA0–OA3, OEB enables OB0–OB3. Its architecture supports bidirectional bus isolation via separate enable pins and eliminates external termination through integrated 25Ω series resistors on all eight outputs.

It uses advanced 0.6/0.8 µm CMOS technology to achieve FAST™-compatible pinout while delivering higher speed (≤3.8 ns max tPLH) and lower static power (≤500 µA ICC) than bipolar equivalents. Input hysteresis ensures noise immunity on slow-rising signals, and rail-to-rail TTL-compatible I/O simplifies interfacing with legacy logic families.

Key Specifications

Pinout & Package

PI74FCT2541ATQ is housed in a 20-pin plastic TSSOP (173 mil width), designated Q package per Pericom's ordering nomenclature. Pin numbering follows standard JEDEC TSSOP layout with inputs on left side (pins 1–10) and outputs on right side (pins 11–20), enabling clean layer routing in high-density designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal non-inverting buffer applications.

Compared with 74F241PC and SN74LVC244APWR, PI74FCT2541ATQ uniquely combines 5V TTL compatibility, integrated 25Ω termination, industrial temperature rating, and sub-4 ns propagation-making it optimal for retrofitting legacy 5V systems requiring improved signal integrity without layout revision.

Availability

PI74FCT2541ATQ is available at Aetrix Electronics and suitable for memory address buffering, system clock fan-out, backplane data interfacing, and legacy ISA bus extension requiring stable component supply and long-term industrial lifecycle support.

Supply support for PI74FCT2541ATQ 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

Pericom Semiconductor was a fabless provider of high-performance interface and timing solutions, acquired by Diodes Incorporated in 2016; its FCT logic portfolio remains widely deployed in industrial and communications infrastructure.

The PI74FCT2XXX series targets high-speed 5V bus interface applications where speed, noise immunity, and pin compatibility with legacy FAST™ logic are critical - especially in memory subsystems and clock distribution networks.

FAQ

Is PI74FCT2541ATQ 5V tolerant on all inputs?

Yes. All inputs meet TTL voltage thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V) and are rated for DC input voltages up to +7.0 V relative to GND, making them fully 5V-tolerant even when driven by higher-voltage sources. This is confirmed in the Absolute Maximum Ratings table and DC Electrical Characteristics section of the PS2011B datasheet.

Can PI74FCT2541ATQ drive a 50 pF load at 25 MHz without external termination?

Yes. Its integrated 25Ω series output resistors are specifically designed to match typical PCB trace impedances (50–75 Ω), suppressing reflections on loads up to 50 pF at frequencies up to 25 MHz. The 3.8 ns max tPLH and low ground bounce ensure timing compliance under these conditions.

What is the function of the two independent output enables (OEA and OEB)?

OEA controls the high-order four outputs (OA0–OA3), while OEB controls the low-order four (OB0–OB3). This allows independent gating of two 4-bit data lanes - for example, enabling address bits A0–A3 while holding A4–A7 in high-Z during partial bus cycles - enhancing flexibility in multiplexed memory or peripheral interfaces.

Does PI74FCT2541ATQ require decoupling capacitors?

Yes. A minimum 0.1 µF ceramic capacitor must be placed between VCC (pin 19) and GND (pin 10), located within 5 mm of the pins. This is required to suppress high-frequency supply noise generated during simultaneous output switching, as specified in Pericom's application guidance for FCT-series devices.