Diodes Incorporated PI74FCT2373ATQ

Overview

PI74FCT2373ATQ from Pericom Semiconductor is an octal transparent latch with 3-state outputs, designed for bus-oriented digital systems requiring data latching and controlled bus isolation. It features built-in 25Ω series output resistors, TTL-compatible input/output levels, industrial temperature range (–40°C to +85°C), and operates at 5.0V ±5%. It is used in microprocessor data bus interfacing where transient noise suppression and low ground bounce are critical.

For engineers reviewing the PI74FCT2373ATQ datasheet, PI74FCT2373ATQ pinout, PI74FCT2373ATQ application, or PI74FCT2373ATQ equivalent, key selection criteria include propagation delay (≤3.8 ns max), output enable/disable timing (tPZH/tPHZ ≤5.5 ns), 25Ω integrated termination, hysteresis on inputs (200 mV), and compatibility with FAST™-series pinouts in TSSOP-20 packaging.

Technical Context

This device implements a synchronous transparent latch architecture: when Latch Enable (LE) is HIGH, D0–D7 pass directly to O0–O7; when LE transitions LOW, the input data present at that instant is captured and held. Output Enable (OE) controls tristate behavior-active LOW assertion places all outputs in high-impedance state, enabling shared bus operation.

It uses advanced 0.6/0.8 µm CMOS process with TTL-level I/O interface, hysteresis on all inputs for noise immunity, and low static power consumption (ICC ≤500 µA). The integrated 25Ω series resistor per output suppresses transmission-line reflections without external termination, reducing PCB component count and layout sensitivity.

Key Specifications

Pinout & Package

PI74FCT2373ATQ is housed in a 20-pin plastic TSSOP (Thin Shrink Small Outline Package), 173 mil wide (JEDEC MO-153), with 0.65 mm lead pitch. Pin 1 is marked by a dot or beveled corner; leads are gull-wing profile for surface-mount reflow assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal transparent latch applications.

Compared with SN74F373N and 74ACT373SCX, PI74FCT2373ATQ uniquely combines TTL compatibility, integrated 25Ω termination, and industrial temperature rating-making it optimal for retrofitting legacy 5V bus systems where signal integrity and drop-in replacement are critical.

Availability

PI74FCT2373ATQ is available at Aetrix Electronics and suitable for microprocessor bus interfacing, memory address latching, industrial I/O expansion, and legacy peripheral bridge logic requiring stable component supply across extended product lifecycles.

Supply support for PI74FCT2373ATQ 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 (now part of Diodes Incorporated) was a fabless provider of high-performance interface, timing, and logic solutions, specializing in low-jitter clock distribution and noise-immune bus interface ICs.

The PI74FCT series was engineered for 5V TTL-compatible digital systems demanding higher speed and lower power than bipolar FAST™ logic, with emphasis on bus noise reduction and industrial reliability.

FAQ

Is PI74FCT2373ATQ pin-compatible with 74F373?

Yes, PI74FCT2373ATQ is pin-compatible with 74F373 and other FAST™-series octal latches in 20-pin packages including TSSOP, SOIC, and DIP. Pin assignments for OE, LE, D0–D7, O0–O7, VCC, and GND match exactly-enabling direct replacement without PCB redesign.

What is the purpose of the 25Ω series resistor on each output?

The 25Ω series resistor is integrated into each output driver to dampen signal reflections on PCB traces, eliminating the need for discrete 25–33Ω series termination resistors. This reduces component count, saves board space, and improves signal integrity on unterminated or marginally terminated buses up to ~50 MHz.

Does PI74FCT2373ATQ support hot-swap or live-insertion?

No, PI74FCT2373ATQ is not hot-swap rated. Its absolute maximum ratings do not include powered insertion protection, and the input clamp diodes (VIK = –0.7 V) are not designed for back-drive tolerance during live insertion. Power sequencing and board-level ESD protection must be implemented externally.

Can OE and LE be tied together for simplified control?

No-OE and LE serve independent functions: LE controls data capture (active HIGH), while OE controls output state (active LOW). Tying them together would prevent independent control of latching vs. bus isolation, violating the truth table and causing undefined output behavior during transitions. They must be driven separately per application timing requirements.