Texas Instruments CD74HCT245M96

Overview

CD74HCT245M96 from Texas Instruments is a high-speed CMOS octal bus transceiver with three-state non-inverting outputs, designed for bidirectional asynchronous data transfer between buses. It operates at 4.5–5.5 V, delivers 33 ns typical propagation delay (A↔B), supports -55°C to +125°C temperature range, and drives up to 15 LSTTL loads-enabling robust inter-bus communication in industrial control backplanes.

For engineers reviewing the CD74HCT245M96 datasheet, CD74HCT245M96 pinout, CD74HCT245M96 application, or CD74HCT245M96 equivalent, key selection criteria include its LSTTL-compatible input thresholds (VIL ≤ 0.8 V, VIH ≥ 2.0 V), 20-pin SOIC (DW) package with 12.8 mm × 7.5 mm footprint, and precise timing behavior under 50 pF load and 4.5 V supply.

Technical Context

The CD74HCT245M96 implements an octal bidirectional buffer architecture controlled by DIR (direction) and OE (output enable) pins. All eight channels switch synchronously: DIR = low enables B→A data flow; DIR = high enables A→B flow; OE = high forces all outputs into high-impedance state. No internal latching or clocking is present-it is purely combinatorial with three-state control.

Its HCT logic family ensures direct compatibility with legacy LSTTL inputs while maintaining CMOS power efficiency. Input leakage stays ≤ ±1 µA at 5.5 V, and three-state output leakage remains ≤ ±10 µA across full temperature range, supporting reliable bus isolation in mixed-voltage systems.

Key Specifications

Pinout & Package

CD74HCT245M96 uses a 20-pin SOIC (DW) package with 1.27 mm pitch, 12.8 mm × 7.5 mm body size, and maximum height of 2.65 mm. Pin 1 is located at top-left corner (Q1 quadrant in tape), with pin numbering counterclockwise.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal bus transceiver applications.

Compared with SN74HCT245N and 74ACT245SCX, CD74HCT245M96 provides optimal balance of industrial temperature support, SOIC surface-mount compatibility, and LSTTL interoperability-making it preferred for space-constrained, high-reliability embedded bus interfaces.

Availability

CD74HCT245M96 is available at Aetrix Electronics and suitable for industrial backplane interfacing, legacy system bus extension, automotive ECU diagnostics interfaces, and test equipment signal routing requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CD74HCT245M96 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 solutions, with decades of heritage in high-reliability logic families.

The CD74HCT245M96 belongs to TI's CD74HCT logic series-designed specifically for robust, drop-in replacement of legacy LSTTL bus transceivers in industrial, aerospace, and automotive systems demanding wide temperature operation and noise immunity.

FAQ

What is the maximum clock frequency supported by CD74HCT245M96 in a bidirectional bus application?

The CD74HCT245M96 does not contain internal clocks or registers-it is a purely combinatorial three-state transceiver. Its usable data rate depends on propagation delay and system timing margins. With 33 ns max tpd and typical setup/hold requirements, CD74HCT245M96 reliably supports sustained bus transfers up to 12–15 MHz in well-terminated 50 pF environments. For higher rates, system-level timing analysis including trace delays and receiver specifications is required.

Does CD74HCT245M96 require external pull-up or pull-down resistors on DIR or OE pins?

No, CD74HCT245M96 does not require external biasing on DIR or OE. Its CMOS inputs have leakage ≤ ±1 µA and defined switching thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V at 4.5–5.5 V). DIR and OE may be driven directly from microcontroller GPIO or other logic outputs. Floating inputs are prohibited per TI layout guidelines-unused control pins must be tied to VCC or GND.

Can CD74HCT245M96 interface between a 3.3 V microcontroller and a 5 V peripheral bus?

No-CD74HCT245M96 is not a level translator. Its inputs are LSTTL-compatible (VIH ≥ 2.0 V), so a 3.3 V MCU output may not guarantee valid high-level recognition across temperature and process variation. Its outputs swing rail-to-rail (0 V to VCC), so driving a 5 V bus from a 3.3 V supply is impossible. For 3.3 V ↔ 5 V interfacing, use dedicated level-shifting transceivers such as TXB0108 or SN74AVCH series instead of CD74HCT245M96.

What is the recommended bypass capacitor value and placement for CD74HCT245M96?

Texas Instruments specifies a 0.1 µF ceramic capacitor placed as close as possible to the VCC pin of CD74HCT245M96, with short, low-inductance traces to both VCC and GND pads. For systems with broadband noise, paralleling a 1 µF capacitor is acceptable. The SOIC-20 DW package's compact layout permits placement within 2 mm of the pin; avoid vias in the capacitor connection path to minimize inductance and preserve high-frequency decoupling effectiveness.

Is CD74HCT245M96 pin-compatible with CD74HC245M96?

Yes-CD74HCT245M96 and CD74HC245M96 share identical SOIC-20 (DW) pinout, mechanical dimensions, and terminal assignments. However, they differ electrically: CD74HC245M96 operates from 2–6 V and has CMOS-input thresholds, while CD74HCT245M96 is restricted to 4.5–5.5 V and accepts LSTTL inputs. Swapping them requires verifying supply voltage and driver compatibility; the pin mapping itself is identical.