Diodes Incorporated 74HC126T14-13

Overview

74HC126T14-13 from Diodes Incorporated is a quadruple 3-state buffer IC with independent active-low enable inputs, designed for bidirectional bus interfacing and signal isolation in 2.0V–6.0V logic systems. It delivers 4mA output drive at 4.5V, features Schmitt-trigger inputs for noise immunity, and supports high-speed operation with 9ns typical propagation delay at 6.0V. Used in PC peripheral interfaces and set-top box data routing.

For engineers reviewing the 74HC126T14-13 datasheet, 74HC126T14-13 pinout, 74HC126T14-13 application, or 74HC126T14-13 equivalent, key selection factors include its TSSOP-14 package footprint, 3-state output timing (tEN/tDIS ≤32ns at 6V), input hysteresis (ΔVIH–VIL = 1.2V min at 4.5V), and ±5μA high-impedance leakage current specification.

Technical Context

The 74HC126 implements four identical CMOS buffer channels, each with dedicated OE# control enabling independent tri-state management of data paths. Its Schmitt-trigger inputs provide 1.2V minimum hysteresis at VCC = 4.5V, ensuring robust noise rejection in electrically noisy environments like HDD controller boards.

All outputs comply with standard HC logic levels and drive capability: VOH ≥ 5.34V (IOH = –5.2mA, VCC = 6.0V), VOL ≤ 0.44V (IOL = 5.2mA, VCC = 6.0V), and support CL = 50pF load conditions per switching characteristic test setup.

Key Specifications

Pinout & Package

TSSOP-14 package: 4.9mm × 4.4mm body, 0.65mm pitch, exposed pad not present, JEDEC MO-153 compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quadruple 3-state buffer applications.

Compared with SN74HC125DR and 74LVC126APW, the 74HC126T14-13 uniquely supports 2.0–6.0V operation in TSSOP-14 while retaining active-low enables - critical for legacy 5V peripheral designs requiring space-constrained packaging and backward-compatible control logic.

Availability

74HC126T14-13 is available at Aetrix Electronics and suitable for PC peripheral interfaces, HDD data bus isolation, and set-top box AV routing requiring stable component supply across industrial temperature ranges (–40°C to +125°C).

Supply support for 74HC126T14-13 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in California and operating design centers across Asia and Europe.

The 74HC126 belongs to Diodes' broad HC logic family, engineered for pin- and function-compatible replacement of legacy TTL and earlier CMOS logic in industrial, computing, and consumer electronics.

FAQ

What is the maximum clock frequency supported by the 74HC126T14-13?

The 74HC126T14-13 is not a clocked device and has no internal clock; its usable data rate depends on propagation delay and load. With 9ns typical tPD at 6.0V and 50pF load, it supports clean signal edges up to ~20MHz toggle frequency in point-to-point routing, assuming proper PCB layout and termination.

Can 74HC126T14-13 drive a 50pF bus capacitance reliably at 4.5V?

Yes - the datasheet specifies switching characteristics under CL = 50pF test conditions. At VCC = 4.5V, tPD is 11ns typical and 30ns max, tEN/tDIS are 15ns typical and 38ns max, confirming full functionality with that load. Output drive (4mA) also meets HC fanout requirements for such capacitance.

Is the TSSOP-14 package of 74HC126T14-13 compatible with reflow soldering per J-STD-020?

Yes - Diodes' TSSOP-14 package is rated for standard lead-free reflow profiles. Peak temperature tolerance is 260°C for 30 seconds, matching J-STD-020D Level 3 requirements. The device's MSL rating is 1 (unlimited floor life), and no pre-bake is required before assembly.

Does 74HC126T14-13 support partial power-down operation?

No - the device lacks Ioff protection. If VCC = 0V while inputs remain biased, DC current may flow through input clamps. Per datasheet Note 6, unused inputs must be tied to VCC or GND; all VCC pins must be powered during operation to ensure predictable 3-state behavior and avoid latch-up risk.