74HC125 Quad Bus Buffer Tri-State IC

Product Overview

The Renesas HD74HC125P is a high-speed CMOS quad bus buffer featuring four independent non-inverting line drivers with 3-state outputs. Designed to operate across a flexible voltage supply range of 2 V to 6 V, this logic integrated circuit offers exceptional noise immunity and ultra-low static power dissipation. It serves as an essential component for digital signal isolation, signal amplification, and multi-drop communication bus management in modern electronic designs.

Technical Specifications and Performance

Utilizing advanced silicon-gate CMOS technology, the HD74HC125P delivers high-speed performance comparable to LSTTL logic while preserving low-power CMOS benefits. The IC achieves rapid propagation delay times of 150 ns at 2 V, 30 ns at 4.5 V, and 25 ns at 6 V. Each of the four buffer channels features an independent active-low output enable control line. When the enable pin is held high, the corresponding output enters a high-impedance state, preventing signal conflicts on shared transmission lines. With drive currents of -7.8 mA (high level) and 7.8 mA (low level), the device reliably drives heavy capacitive bus loads across an extended operating temperature range of -40 C to +85 C.

Applications and System Integration

The HD74HC125P is widely deployed in microprocessor memory mapping, bi-directional data bus interfacing, and peripheral line driving. It is ideal for routing digital signals across long PCB traces, isolating subsystems in industrial controllers, managing multiplexed sensor signals, and preventing bus contention in multi-master microcontroller environments.

Packaging and Prototyping Features

Encapsulated in a standard 14-pin Plastic Dual In-Line Package (PDIP-14), the HD74HC125P is fully RoHS compliant. The through-hole mounting format makes it optimal for prototyping on solderless breadboards, installation in standard IC sockets, and direct wave soldering into industrial printed circuit boards.