Texas Instruments SN74LV244ANSR

Overview

SN74LV244ANSR from Texas Instruments is an octal 3-state buffer/driver IC designed for bidirectional signal buffering in bus-oriented systems. It features dual 4-bit groups with independent output-enable (OE) controls, operates from 2 V to 5.5 V, delivers ≤6.5 ns propagation delay at 5 V, supports mixed-mode voltage interfacing, and includes Ioff for partial-power-down operation. It is used in server backplanes and telecom infrastructure to isolate and strengthen digital control signals between FPGAs and peripheral ASICs.

For engineers reviewing the SN74LV244ANSR datasheet, SN74LV244ANSR pinout, SN74LV244ANSR application, or SN74LV244ANSR equivalent, this page provides verified functional identity, confirmed SOIC-20 package mapping, validated 20-pin terminal roles, real-world timing and drive specifications, and two rigorously confirmed alternative parts for bus driver selection.

Technical Context

The SN74LV244ANSR implements two independent 4-bit noninverting buffer sections, each with a dedicated active-low output-enable input (1OE, 2OE). Its CMOS inputs accept TTL- and LVCMOS-compatible logic levels across the full 2–5.5 V supply range, enabling mixed-voltage domain interfacing without level shifters.

All eight outputs are balanced 3-state CMOS drivers capable of sourcing or sinking up to ±16 mA at 4.5–5.5 V, with guaranteed VOL ≤ 0.55 V and VOH ≥ 3.8 V under load. The device incorporates Ioff circuitry that disables all outputs and limits leakage to ≤5 µA when VCC = 0 V, supporting hot-insertion and power sequencing in modular systems.

Key Specifications

Pinout & Package

SN74LV244ANSR is packaged in a 20-pin SOIC (DW) body measuring 12.80 mm × 10.3 mm, with standard 0.050″ (1.27 mm) lead pitch and gull-wing leads. Thermal resistance RθJA = 102.3°C/W enables reliable operation at full drive strength in ambient temperatures up to +85°C without forced airflow.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LV244ANSR, SN74LVC244APWR offers higher speed but sacrifices 5 V operation and Ioff robustness, while 74ALVC244MTCX improves noise immunity at the cost of voltage range and hot-swap capability - making SN74LV244ANSR the only choice for industrial 2–5.5 V mixed-rail systems requiring partial-power-down support.

Availability

SN74LV244ANSR is available at Aetrix Electronics and suitable for server backplane buffering, LED display column driving, telecom line card interfacing, and motor-drive control logic isolation requiring stable component supply across extended temperature and mixed-voltage conditions.

Supply support for SN74LV244ANSR 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 for industrial, automotive, and communications markets.

The SN74LV244ANSR belongs to TI's LV logic family, engineered for high-speed, low-voltage operation with robust noise immunity and mixed-voltage interoperability in demanding infrastructure applications.

FAQ

What is the maximum propagation delay of the SN74LV244ANSR at 5 V?

The SN74LV244ANSR has a maximum propagation delay (tpd) of 6.5 ns when operating at VCC = 5 V with a 50-pF load, as specified in the Switching Characteristics table. This value is measured from input transition to valid output transition under worst-case process, voltage, and temperature conditions, ensuring timing margin for high-speed bus applications.

Does the SN74LV244ANSR support partial-power-down mode?

Yes, the SN74LV244ANSR supports partial-power-down mode via its Ioff feature. When VCC = 0 V, all outputs enter high-impedance state and input/output leakage remains ≤5 µA, preventing current backflow into unpowered sections - a key requirement for hot-pluggable telecom and server modules.

Can the SN74LV244ANSR drive LEDs directly?

Yes, the SN74LV244ANSR can drive LEDs directly: each output sources or sinks up to ±16 mA at 4.5–5.5 V, sufficient for standard indicator or display column LEDs. For constant-current operation, connect the LED anode to VCC and cathode to an SN74LV244ANSR output pin, relying on VOL ≤ 0.55 V to set forward current.

What is the recommended termination for unused inputs on the SN74LV244ANSR?

Unused inputs on the SN74LV244ANSR must be tied to either VCC or GND - never left floating. A 10-kΩ pull-up or pull-down resistor is recommended to ensure stable logic states, prevent oscillation, and minimize power consumption, especially in systems with slow or intermittent input transitions.

Is the SN74LV244ANSR pin-compatible with other octal buffer families?

No, the SN74LV244ANSR is not pin-compatible with standard 74LS244 or 74HC244 variants due to differences in enable polarity and internal grouping. Its 1OE and 2OE pins are active-low and control separate 4-bit sections, whereas legacy parts often use single or inverted enables - PCB layout must match the SN74LV244ANSR-specific 20-pin SOIC footprint and signal assignment.