Texas Instruments CD74ACT258M

Overview

CD74ACT258M from Texas Instruments is a quad 2-input multiplexer with inverting three-state outputs, designed for high-speed data routing in digital logic systems. It operates at 4.5–5.5 V, delivers 2.4 ns typical propagation delay (V_CC = 5 V, C_L = 50 pF), supports ±24 mA output drive, and features SCR-latchup-resistant CMOS process - used in address/data bus selection and function generation circuits.

For engineers reviewing the CD74ACT258M datasheet, CD74ACT258M pinout, CD74ACT258M application, or CD74ACT258M equivalent, key selection criteria include its inverting output architecture, 5-V ACT logic family compatibility, 16-pin SOIC package, -55°C to +125°C operating range, and three-state enable control for bus sharing.

Technical Context

The CD74ACT258M implements four independent 2:1 multiplexers, each selecting between two inputs (I₀/I₁) based on a common select line (S), with inverted outputs (Y). Its active-low Output Enable (OE) places all outputs in high-impedance state when asserted, enabling shared-bus operation without external gating.

It uses Advanced CMOS Logic (ACT) technology, delivering bipolar FAST™/AS speed with CMOS power efficiency. Input thresholds are TTL-compatible (V_IL ≤ 0.8 V, V_IH ≥ 2.0 V), and it drives 50 Ω transmission lines while maintaining balanced propagation delays across channels.

Key Specifications

Pinout & Package

CD74ACT258M is supplied in a 16-pin SOIC (D) package (9.9 mm × 6.0 mm body, 1.75 mm nominal height), with gull-wing leads and RoHS-compliant NiPdAu finish. Thermal performance is characterized by R_θJA = 119.9°C/W (JEDEC standard board).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 2-input multiplexer applications.

Compared with CD74ACT257M and SN74ACT258N, the CD74ACT258M provides inverting outputs in a space-efficient SOIC package optimized for surface-mount production, while maintaining full functional equivalence except for output polarity and package form factor.

Availability

CD74ACT258M is available at Aetrix Electronics and suitable for industrial control, aerospace avionics, and test instrumentation requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CD74ACT258M 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 CD74ACT258M belongs to TI's Advanced CMOS Logic (ACT) family, engineered for 5-V systems demanding TTL-compatible interfacing, high speed, and robustness in harsh environments - particularly where inverting multiplexing is required.

FAQ

What is the output logic polarity of the CD74ACT258M?

The CD74ACT258M provides inverting outputs: each Y output is the logical complement of the selected input (I₀ or I₁). This distinguishes it from the non-inverting CD74ACT257M. The inversion is inherent to the device architecture and cannot be disabled; system-level logic design must account for this polarity when connecting to downstream latches or decoders.

Does the CD74ACT258M support operation below 4.5 V?

No - the CD74ACT258M is specified only for 4.5 V to 5.5 V operation per TI's Recommended Operating Conditions. Unlike AC-series variants (e.g., CD74AC258), the ACT version does not support 1.5–5.5 V operation. Attempting to power CD74ACT258M below 4.5 V may result in undefined logic states, increased propagation delay, or failure to meet output drive specifications.

How is the Output Enable (OE) pin used in system design with CD74ACT258M?

The OE pin on CD74ACT258M is active-low and controls all four outputs simultaneously. When OE is HIGH, all Y outputs enter high-impedance state regardless of S or input states - enabling safe bus sharing. In practice, OE is typically driven by a microcontroller GPIO or bus arbiter signal synchronized with data valid windows to prevent bus contention during transitions.

Is the CD74ACT258M pin-compatible with CD74ACT257M?

Yes - CD74ACT258M and CD74ACT257M share identical 16-pin SOIC (D) package, pinout, and DC/AC electrical specifications, differing only in output polarity (inverting vs. non-inverting). This allows direct PCB replacement if downstream logic accommodates the polarity change; no layout modification is required beyond verifying functional correctness of the inverted outputs.

What thermal considerations apply to CD74ACT258M in continuous operation?

CD74ACT258M has a junction-to-ambient thermal resistance (R_θJA) of 119.9°C/W in SOIC package. At maximum rated supply (5.5 V) and full output loading, power dissipation remains low (<15 mW static), but dynamic loading increases dissipation. For sustained operation at 125°C ambient, ensure adequate PCB copper area under the package and avoid stacking heat-generating components nearby to maintain junction temperature within absolute maximum rating.