Texas Instruments SN74LVC244ADB

Overview

SN74LVC244ADB from NXP Semiconductors is an octal non-inverting 3-state buffer/line driver in SSOP20 package, operating from 1.2 V to 3.6 V supply, with 5.5 V-tolerant inputs, Schmitt-trigger inputs for noise immunity, and −40 °C to +125 °C temperature range. It enables bidirectional voltage translation between 3.3 V and 5 V logic domains in microcontroller I/O expansion and bus isolation applications.

For engineers reviewing the SN74LVC244ADB datasheet, SN74LVC244ADB pinout, SN74LVC244ADB application, or SN74LVC244ADB equivalent, key selection criteria include 3-state enable timing (tdis ≤ 7.5 ns at 3.3 V), input voltage tolerance (up to 5.5 V), low ICC (≤40 µA), output drive capability (±24 mA), and SSOP20 footprint compatibility with space-constrained PCB layouts.

Technical Context

This device implements dual 4-bit non-inverting buffers with independent active-low 3-state control (1OE, 2OE). Each group drives four outputs (1Y0–1Y3, 2Y0–2Y3) from corresponding inputs (1A0–1A3, 2A0–2A3), with Schmitt-trigger inputs ensuring robust operation under slow-rising or noisy signals.

It supports mixed-voltage interfacing: inputs accept 0–5.5 V regardless of VCC (1.2–3.6 V), and outputs in 3-state mode tolerate up to 5.5 V. No bus-hold circuit is present-this feature applies only to the 74LVCH244A variant, not SN74LVC244ADB.

Key Specifications

Pinout & Package

SN74LVC244ADB uses a 20-pin plastic shrink small outline package (SSOP20), body width 5.3 mm (SOT339-1), with gull-wing leads and standard 0.65 mm pitch. Pin 1 is marked by a notch or index area.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal buffer/line driver applications.

Compared with SN74LVCH244ADB, SN74LVC244ADB offers lower cost and identical timing/performance where bus-hold is unnecessary; versus 74ALVC244PW, it trades minor speed reduction for broader voltage flexibility and robust 5 V tolerance - critical for mixed-supply industrial interfaces.

Availability

SN74LVC244ADB is available at Aetrix Electronics and suitable for industrial control systems, embedded instrumentation, and communications infrastructure requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for SN74LVC244ADB 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

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The 74LVC family delivers low-voltage, high-speed CMOS logic with enhanced noise immunity and mixed-voltage interoperability - designed specifically for power-efficient, space-constrained embedded systems demanding robust signal integrity.

FAQ

What is the maximum input voltage rating for SN74LVC244ADB?

The SN74LVC244ADB supports input voltages up to 5.5 V, independent of VCC level. This 5 V tolerance allows direct interfacing with legacy 5 V TTL or CMOS outputs while operating from 1.2 V to 3.6 V supply - a key enabler for mixed-voltage system design without external level shifters. Absolute maximum rating is +6.5 V, but operation above 5.5 V risks reliability degradation.

Does SN74LVC244ADB include bus-hold functionality on its inputs?

No, SN74LVC244ADB does not include bus-hold circuitry. That feature is exclusive to the 74LVCH244A variant (e.g., SN74LVCH244ADB). The SN74LVC244ADB requires external pull-up or pull-down resistors on unused inputs to prevent floating states. This distinction is explicitly documented in NXP's datasheet Section 2 (Features and benefits) and Table 6 (Static characteristics notes).

What is the typical propagation delay of SN74LVC244ADB at 3.3 V supply?

At VCC = 3.3 V and TA = 25 °C, the typical propagation delay (tpd) of SN74LVC244ADB is 2.9 ns (min 1.5 ns, max 5.9 ns over −40 °C to +125 °C). This value applies to both A→Y paths (e.g., 1A0 to 1Y0) and is measured under standard load conditions (CL = 50 pF, RL = 500 Ω), supporting reliable operation in 100+ MHz digital interfaces.

Can SN74LVC244ADB operate from a 1.2 V supply?

Yes, SN74LVC244ADB is fully specified down to 1.2 V supply voltage. At this minimum VCC, it maintains functional operation with VIH/VIL thresholds scaled accordingly (e.g., VIH = 1.08 V), and supports input transition rates up to 20 ns/V. This ultra-low-voltage capability enables integration into energy-harvesting and battery-powered edge devices where power efficiency is critical.

What package type is used for SN74LVC244ADB?

SN74LVC244ADB uses the SSOP20 (shrink small outline package) with 20 gull-wing leads, body width 5.3 mm, and 0.65 mm lead pitch (JEDEC MO-150, NXP SOT339-1). Its compact footprint provides 30% board area reduction versus standard SO20, making it ideal for dense PCB layouts in portable and modular industrial electronics.