Diodes Incorporated 74HC126S14-13

Overview

74HC126S14-13 from Diodes Incorporated is a quadruple 3-state buffer IC with independent active-low enable inputs, designed for bidirectional bus interface and signal isolation in 2.0V–6.0V logic systems. It delivers 4mA drive capability 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 data routing and notebook I/O expansion.

For engineers reviewing the 74HC126S14-13 datasheet, 74HC126S14-13 pinout, 74HC126S14-13 application, or 74HC126S14-13 equivalent, key selection criteria include 3-state output timing (tEN/tDIS ≤32ns at 6V), input hysteresis (ΔVIN ≈0.8V at 4.5V), leakage current (±5μA in Z-state), and SO-14 thermal resistance (θJA = 120°C/W).

Technical Context

The 74HC126 implements four identical CMOS buffer stages, each with separate OE-bar control enabling independent tri-state management per channel. All inputs incorporate Schmitt-trigger action with hysteresis of ~0.8V at VCC = 4.5V, ensuring robust noise rejection in noisy digital environments.

It operates across industrial temperature range (−40°C to +125°C) with guaranteed DC specs including VIH ≥3.15V and VIL ≤1.35V at 4.5V supply, and AC performance validated at CL = 50pF load with tPD = 9–26ns depending on VCC and temperature grade.

Key Specifications

Pinout & Package

74HC126S14-13 is housed in a 14-pin SOIC (SO-14) package with 1.27mm pitch, 8.6mm × 3.9mm body, and 1.73mm max height - optimized for automated SMT assembly and board-level thermal dissipation (θJA = 120°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC125DR and MC74HC126ADTR2G, the 74HC126S14-13 uniquely combines Schmitt-trigger inputs with industry-standard SO-14 packaging and verified 125°C operation - making it optimal for cost-sensitive consumer electronics where noise immunity and layout simplicity are prioritized over ultra-low quiescent current or extreme temperature range.

Availability

74HC126S14-13 is available at Aetrix Electronics and suitable for PC motherboard design, notebook I/O expansion, and set-top box front-panel control requiring stable component supply and full RoHS/Green compliance.

Supply support for 74HC126S14-13 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, specializing in high-reliability, energy-efficient components for computing, consumer, and industrial markets.

The 74HC126 belongs to Diodes' HC logic family - engineered for compatibility with industry-standard 74-series functions while enhancing noise immunity, ESD robustness, and wide-voltage operation for modern mixed-signal systems.

FAQ

What is the maximum clock frequency supported by the 74HC126S14-13?

The 74HC126S14-13 does not operate on a clock; it is an asynchronous buffer. Its usable data rate depends on propagation delay and load capacitance. With CL = 50pF and VCC = 6.0V, tPD is 9ns (typ), supporting reliable edge rates up to ~35MHz for clean signal transitions - verified via switching characteristics in DS35327 Rev. 3-2.

Can unused inputs be left floating?

No. Per Recommended Operating Conditions (Note 6), all unused inputs must be tied to VCC or GND to prevent undefined logic states, increased ICC, and potential oscillation. Floating inputs may draw excessive current due to CMOS input structure and violate absolute maximum ratings for IIK.

Is the 74HC126S14-13 compatible with 5V TTL logic levels?

Yes. At VCC = 5.0V, VIH = 3.5V (min) and VIL = 1.5V (max) meet TTL input thresholds. Outputs deliver VOH ≥4.4V and VOL ≤0.33V at 4mA load - exceeding TTL VOH (2.4V) and VOL (0.4V) requirements, enabling direct interfacing without level shifters.

Does this device support hot-swap or live-insertion?

Not inherently. While its 3-state outputs prevent bus contention, the device lacks powered-off protection (Ioff). During hot insertion, VCC ramp-up before signal stabilization may cause latch-up or excessive current if inputs exceed VCC + 0.5V. Use with series resistors or dedicated hot-swap controllers is recommended for such applications.