Texas Instruments CD74HCT253MT

Overview

CD74HCT253MT from Texas Instruments is a dual 4-to-1 line selector/multiplexer with three-state outputs, designed for digital signal routing in bus-oriented systems. It features common select inputs (S0, S1), independent output-enable controls (1OE, 2OE), operates from 4.5 V to 5.5 V, supports -55°C to +125°C industrial temperature range, and delivers 38 ns typical propagation delay (data to output, VCC = 4.5 V, CL = 50 pF).

For engineers reviewing the CD74HCT253MT datasheet, CD74HCT253MT pinout, CD74HCT253MT application, or CD74HCT253MT equivalent, this device serves as a high-noise-immunity, LSTTL-compatible multiplexer for logic-level data selection, bus isolation, and signal gating in embedded control, instrumentation, and industrial interface circuits.

Technical Context

The CD74HCT253MT implements two independent 4-input multiplexers sharing select lines S0 and S1, with each section driving a three-state output (1Y, 2Y) controlled by dedicated enable pins (1OE, 2OE). Its HCT logic family ensures direct compatibility with LSTTL input thresholds (VIL ≤ 0.8 V, VIH ≥ 2.0 V) while maintaining CMOS power efficiency.

Propagation delays are balanced across select-to-output (40 ns max) and data-to-output (48 ns max) paths at VCC = 4.5 V and CL = 50 pF, and disable/enable timing (tPLZ/tPZH) is specified at 38 ns/38 ns max under identical conditions - enabling predictable bus turnaround in time-critical digital systems.

Key Specifications

Pinout & Package

CD74HCT253MT is housed in a 16-pin SOIC (Small Outline Integrated Circuit) package with standard 1.27 mm pitch, JEDEC MS-012AC compliant, and RoHS-compliant NIPDAU lead finish. Thermal resistance θJA is 73°C/W (typical).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual 4-to-1 multiplexer applications.

Compared with SN74HCT253D, CD74HCT253MT offers identical functionality and performance but uses an older TI part numbering scheme; versus 74HCT253PW, it provides superior thermal dissipation and drop-in compatibility with existing SOIC footprints - making CD74HCT253MT optimal for industrial upgrades and legacy system maintenance.

Availability

CD74HCT253MT is available at Aetrix Electronics and suitable for industrial control, automotive diagnostics, and test equipment applications requiring stable component supply, extended temperature support, and long-term obsolescence management.

Supply support for CD74HCT253MT 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 over 90 years of innovation in high-reliability components.

The CD74HCT253MT belongs to TI's CD74HCT high-speed CMOS logic family, engineered for seamless integration into mixed-signal systems requiring TTL-compatible inputs, low power, and extended temperature operation.

FAQ

What is the supply voltage range supported by the CD74HCT253MT?

The CD74HCT253MT operates strictly within 4.5 V to 5.5 V. Unlike HC variants, it does not support 2 V or 6 V rails. Operation outside this window risks undefined logic states or damage, as confirmed by absolute maximum ratings (VCC = –0.5 V to 7 V) and DC operating conditions in the TI datasheet SCHS170B.

Does the CD74HCT253MT support true three-state outputs, and what is the leakage current in that mode?

Yes, the CD74HCT253MT provides true three-state outputs. When either 1OE or 2OE is HIGH, the corresponding Y output enters high-impedance mode with leakage current ≤ ±5 µA (measured at VCC = 5.5 V, VO = VCC or GND), per the HCT DC Electrical Specifications table in the official datasheet.

Can the CD74HCT253MT be used with 3.3 V logic systems?

No - the CD74HCT253MT requires 4.5 V to 5.5 V for guaranteed operation and TTL-compatible input thresholds. Driving its inputs from 3.3 V violates the minimum VIH = 2.0 V specification only under 4.5–5.5 V VCC; at lower VCC, VIH is undefined. Use CD74HC253MT for 3.3 V–compatible designs.

What is the maximum clock/data frequency supported by the CD74HCT253MT in a typical application?

The CD74HCT253MT does not operate on a clock; it is combinatorial. Its usable data rate depends on propagation delay (max 60 ns select-to-output at VCC = 4.5 V) and system setup/hold margins. For reliable operation with 50 pF load, maximum toggle rate is ~8 MHz (1/(2 × 60 ns)), though actual throughput depends on enable timing and bus settling.

Is the CD74HCT253MT pin-compatible with the CD74HC253MT?

Yes - CD74HCT253MT and CD74HC253MT share identical SOIC-16 pinout, terminal functions, and package dimensions. However, they differ electrically: CD74HC253MT supports 2–6 V operation and CMOS input thresholds, while CD74HCT253MT mandates 4.5–5.5 V and LSTTL-compatible inputs. Swapping requires verifying supply and driver compatibility.