Texas Instruments 74ACT11257DBR

Overview

74ACT11257DBR from Texas Instruments is a quadruple 2-line-to-1-line data selector/multiplexer with 3-state outputs, designed for bus-organized systems requiring signal routing from four 4-bit data sources. It operates over –40°C to 85°C, supports 4.5 V–5.5 V supply, delivers ±24 mA output drive, and features 1.5 ns minimum propagation delay (tPLH/tPHL) with TTL-compatible inputs.

For engineers reviewing the 74ACT11257DBR datasheet, 74ACT11257DBR pinout, 74ACT11257DBR application, or 74ACT11257DBR equivalent, key selection criteria include 3-state bus interface capability, flow-through pinout for PCB layout optimization, EPIC CMOS process immunity (500 mA latch-up), and SSOP-20 package compatibility with high-density system designs.

Technical Context

The 74ACT11257DBR implements four independent 2:1 multiplexers sharing a common select (A/B) and output-enable (OE) control. Each channel routes either input A or B to its dedicated 3-state output (1Y–4Y) based on the logic level of A/B, while OE independently disables all outputs to high-impedance state.

Its EPIC 1-µm CMOS process ensures TTL-voltage compatibility at inputs (VIH = 2 V min, VIL = 0.8 V max), rail-to-rail output swing (VOH ≥ 3.94 V at VCC = 4.5 V, VOL ≤ 0.44 V), and low dynamic power dissipation (Cpd = 13 pF when outputs disabled).

Key Specifications

Pinout & Package

74ACT11257DBR uses a 20-pin Shrink Small-Outline Package (SSOP-DB) with 0.65 mm pitch, 7.5 mm × 5.6 mm body, and center-aligned VCC/GND pins to minimize switching noise. Pin 1 is located at top-left (Q1 quadrant) per JEDEC MO-150.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar data selector/multiplexer applications.

Compared with 74ACT157DWR and SN74LVC157APW, the 74ACT11257DBR uniquely combines 5 V operation, flow-through SSOP-20 layout, center-pin power/ground, and 500 mA latch-up immunity - making it optimal for noise-sensitive, high-reliability bus multiplexing where physical layout and robustness are design priorities.

Availability

74ACT11257DBR is available at Aetrix Electronics and suitable for industrial control systems, embedded computing platforms, and test equipment requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for 74ACT11257DBR 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 experience in high-reliability industrial and automotive ICs.

The 74ACT11257DBR belongs to TI's ACT advanced CMOS logic family, engineered for 5 V systems demanding TTL compatibility, low noise, and robust bus interfacing in industrial and computing applications.

FAQ

What is the operating voltage range for the 74ACT11257DBR?

The 74ACT11257DBR operates over a supply voltage range of 4.5 V to 5.5 V. This range ensures full compatibility with standard 5 V TTL and CMOS logic families while maintaining specified timing, drive strength, and noise margins across the entire industrial temperature range (–40°C to +85°C). Operation outside this range may result in undefined behavior or damage.

Does the 74ACT11257DBR support true 3-state outputs?

Yes, the 74ACT11257DBR provides true 3-state outputs. When the active-low output-enable (OE) input is high, all four Y outputs (1Y–4Y) enter a high-impedance state with leakage current ≤ ±0.5 µA at VCC = 5.5 V. This enables safe connection to shared data or address buses without contention, as confirmed in the electrical characteristics table under parameter IOZ.

What package type is used for the 74ACT11257DBR?

The 74ACT11257DBR uses a 20-pin Shrink Small-Outline Package (SSOP) with DB package drawing, measuring 7.5 mm × 5.6 mm with 0.65 mm lead pitch. It complies with JEDEC MO-150 and features center-aligned VCC (pins 17–20) and GND (pins 9, 14) for optimized high-speed layout and reduced switching noise.

How does the flow-through architecture benefit PCB design for the 74ACT11257DBR?

The flow-through architecture places inputs (A/B, 1A–4B) on the left side and outputs (1Y–4Y) on the right side of the 74ACT11257DBR SSOP-20 package. This allows straight-line trace routing between adjacent components - eliminating vias, reducing crosstalk, and shortening net lengths - which directly improves signal integrity and simplifies layout in dense bus-oriented systems.

Is the 74ACT11257DBR latch-up immune, and what is the rated level?

Yes, the 74ACT11257DBR exhibits 500 mA typical latch-up immunity at 125°C, as verified per JEDEC JESD78. This immunity stems from Texas Instruments' EPIC (Enhanced-Performance Implanted CMOS) 1-µm process and is critical for reliability in electrically noisy industrial environments where transient currents could otherwise trigger destructive parasitic SCR conduction.