Texas Instruments SN74ACT244NSRG4

Overview

SN74ACT244NSRG4 from Texas Instruments is an octal 3-state buffer/driver IC designed for bus-oriented data transmission, clock distribution, and memory address driving in 5-V TTL-compatible systems. It features dual 4-bit channels with independent active-low output enables, 9.5 ns maximum propagation delay at 5 V, ±24 mA output drive per channel, and operation across –40°C to +85°C.

For engineers reviewing the SN74ACT244NSRG4 datasheet, SN74ACT244NSRG4 pinout, SN74ACT244NSRG4 application, or SN74ACT244NSRG4 equivalent, key selection criteria include 3-state bus isolation capability, TTL-input compatibility, high-current drive strength, thermal performance in SO package, and industrial-temperature reliability.

Technical Context

The SN74ACT244NSRG4 implements two independent 4-bit non-inverting buffer sections, each controlled by a dedicated active-low output-enable (OE) input. Its logic architecture supports bidirectional bus interfacing when paired with complementary drivers, and its TTL-compatible inputs accept 2 V minimum high-level voltage at 5 V VCC.

It operates strictly within 4.5 V–5.5 V supply range, with guaranteed switching performance up to 10 ns typical tPLH/tPHL and 9.5 ns max, while maintaining high-impedance outputs during OE assertion - critical for preventing bus contention in shared-data-path systems.

Key Specifications

Pinout & Package

SN74ACT244NSRG4 is packaged in a 20-pin SO (Small Outline) package (NS), 7.5 mm × 12.8 mm body, 1.27 mm pitch, RoHS-compliant, moisture sensitivity level 1, peak reflow 260°C.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal 3-state buffer applications.

Compared with SN74LS244N, SN74ACT244NSRG4 delivers 2.5× faster switching and 60% higher drive; versus SN74LVC244APWR, it maintains native 5-V operation but consumes more static power and lacks 3.3-V compatibility.

Availability

SN74ACT244NSRG4 is available at Aetrix Electronics and suitable for LED display drivers, server memory address buffering, and telecom switching networks requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for SN74ACT244NSRG4 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 50 years of innovation in high-reliability logic interfaces and power management.

The SNx4ACT244 product line was engineered for high-density, high-speed 5-V bus interfacing - targeting memory subsystems, clock distribution networks, and industrial control backplanes where TTL compatibility and robust 3-state isolation are essential.

FAQ

What is the operating voltage range for SN74ACT244NSRG4?

The SN74ACT244NSRG4 operates over a strict 4.5 V to 5.5 V supply range. Operation outside this window is not characterized or guaranteed. Its TTL-compatible inputs accept 2 V minimum high-level voltage at 5 V VCC, and all unused inputs must be tied to VCC or GND to prevent floating states that could cause excessive current draw or undefined outputs in the SN74ACT244NSRG4.

How does the 3-state output control work on SN74ACT244NSRG4?

The SN74ACT244NSRG4 uses two active-low output-enable inputs (1OE and 2OE) - one per 4-bit section. When an OE pin is logic low, its corresponding four Y outputs pass non-inverted data from the A inputs; when high, those outputs enter high-impedance state. This enables bus sharing without contention, and OE should be pulled up to VCC during power-up to ensure safe default isolation in the SN74ACT244NSRG4.

Can SN74ACT244NSRG4 drive LEDs directly?

Yes, SN74ACT244NSRG4 can drive LEDs directly with appropriate current-limiting resistors. Each output delivers ±24 mA, sufficient for standard indicator LEDs. For a 5 V supply and red LED (VF ≈ 1.8 V), a 150 Ω resistor limits current to ~21 mA - within SN74ACT244NSRG4's rated IOL/IOH and avoids exceeding VOL/VOH specs. Always verify LED forward voltage and thermal derating in the final SN74ACT244NSRG4 design.

What is the thermal resistance of SN74ACT244NSRG4 in its SO package?

In the SO (NS) package, SN74ACT244NSRG4 has a junction-to-ambient thermal resistance (RθJA) of 106.2°C/W and junction-to-board (RθJB) of 71.2°C/W. These values assume standard JEDEC 2-layer board conditions. For sustained 24 mA per output operation, board layout must include adequate copper pour and thermal vias to keep junction temperature below 125°C - especially critical in enclosed industrial enclosures where ambient exceeds 70°C for the SN74ACT244NSRG4.

Is SN74ACT244NSRG4 pin-compatible with other SN74ACT244 variants?

Yes, SN74ACT244NSRG4 shares identical pinout and logic functionality with all SN74ACT244 variants across SOIC (DW), SSOP (DB), TSSOP (PW), VSSOP (DGS), VQFN (RKS), and PDIP (N) packages. The NS package is functionally and electrically interchangeable - differences lie only in thermal performance, board space, and reflow profile. No PCB redesign is needed when substituting SN74ACT244NSRG4 into existing SO footprints.