Texas Instruments CD74HCT368E

Overview

CD74HCT368E from Texas Instruments is a high-speed CMOS hex inverting buffer/line driver with three-state outputs, designed for bus interface and data routing in industrial control and instrumentation systems. It features dual independent three-state enables (OE1, OE2), 4.5 V–5.5 V operation, typical propagation delay of 11 ns at 5 V/15 pF, and ±4 mA output drive capability.

For engineers reviewing the CD74HCT368E datasheet, CD74HCT368E pinout, CD74HCT368E application, or CD74HCT368E equivalent, this page delivers verified electrical specs, functional pin mapping, real-world use cases, and validated alternative parts - all aligned to TI's SCHS181E production data sheet (Rev. FEBRUARY 2022).

Technical Context

The CD74HCT368E implements six independent inverting buffer channels, grouped as four (Y1–Y4) controlled by OE1 and two (Y5–Y6) controlled by OE2. Each output supports high-impedance (Z) state when its enable is high, enabling bidirectional bus sharing without external logic.

It uses silicon-gate CMOS technology with TTL-compatible inputs (VIL ≤ 0.8 V, VIH ≥ 2.0 V), operates across –55°C to +125°C, and delivers LSTTL-equivalent speed while consuming significantly less power than legacy TTL buffers.

Key Specifications

Pinout & Package

CD74HCT368E is supplied in a 16-pin plastic dual in-line package (PDIP-N), with 19.31 mm × 6.35 mm body size and through-hole mounting. Pin 1 is marked with a notch or dot; pin numbering follows standard DIP convention (counter-clockwise from top-left corner).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar hex inverting three-state buffer applications.

Compared with CD74HCT368E, SN74HCT368N offers enhanced long-term supply continuity and tighter parametric consistency, while MC74HCT368ANG provides automotive-grade reliability validation - both retain full functional and pin compatibility for drop-in replacement in existing 5 V logic designs.

Availability

CD74HCT368E is available at Aetrix Electronics and suitable for industrial PLCs, test equipment signal routing, military avionics interfaces, and legacy system emulation hardware requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CD74HCT368E 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic ICs, with decades of heritage in high-reliability logic families including the 74HCT series.

The CD74HCT368E belongs to TI's industry-standard 74HCT logic family, engineered for seamless LSTTL-to-CMOS migration in industrial, aerospace, and defense systems demanding wide temperature operation and low power.

FAQ

What is the maximum clock/data rate supported by CD74HCT368E?

The CD74HCT368E is not a clocked device but a combinational buffer; its usable data rate depends on propagation delay and load. With 11 ns typical tPD at 5 V/15 pF, it supports clean signal routing up to ~45 MHz in point-to-point configurations. For bus applications, edge integrity into 50 pF loads remains robust below 20 MHz.

Does CD74HCT368E require external pull-up or pull-down resistors on unused inputs?

Yes - per TI's layout guidelines, all unused inputs of CD74HCT368E must be terminated to VCC or GND to prevent floating states. Leaving inputs unconnected risks undefined outputs, increased ICC, and potential latch-up. Tie unused A inputs to GND if inactive-low logic is acceptable; otherwise use 10 kΩ pull-downs.

Can CD74HCT368E operate reliably at 3.3 V supply voltage?

No - CD74HCT368E is specified only for 4.5 V to 5.5 V operation. At 3.3 V, input thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V) become non-compliant, and output drive degrades significantly. For 3.3 V systems, use CD74HC368E (2–6 V) or SN74LVC368A (1.65–3.6 V) instead.

How does the dual-enable architecture of CD74HCT368E improve system design?

The dual-enable structure (OE1 for Y1–Y4, OE2 for Y5–Y6) allows granular bus control: e.g., four data lines can remain active while two status/control lines enter high-Z during arbitration. This eliminates need for additional logic gates or multiplexers in partial-bus isolation schemes used in modular I/O systems.

Is CD74HCT368E pin-compatible with the obsolete 74LS368?

Yes - CD74HCT368E is functionally and pin-compatible with 74LS368, sharing identical pinout, logic behavior (inverting three-state), and DC input thresholds. It replaces LS368 directly in 5 V systems, offering lower power (μA vs mA ICC), higher noise immunity, and extended temperature range without PCB changes.