Texas Instruments SN74LVT244BDB

Overview

SN74LVT244BDB from Texas Instruments is a 3.3-V ABT octal buffer/driver with 3-state outputs, designed for mixed-mode signal operation (5-V inputs/outputs with 3.3-V V_CC). It features dual 4-bit drivers, I_off and power-up 3-state for hot insertion, supports unregulated battery operation down to 2.7 V, and delivers t_PLH/t_PHL ≤ 3.5 ns at V_CC = 3.3 V - used in backplane interface and voltage-level translation between 3.3-V logic and legacy 5-V systems.

For engineers reviewing the SN74LVT244BDB datasheet, SN74LVT244BDB pinout, SN74LVT244BDB application, or SN74LVT244BDB equivalent, key selection criteria include hot-insertion support via I_off, 2.7–3.6 V supply range, 64 mA output drive capability, low ground bounce (<0.8 V), and SSOP-20 package compatibility with industrial temperature range (−40°C to 85°C).

Technical Context

This device implements two independent 4-bit noninverting buffers, each controlled by a dedicated output-enable (OE) input. When OE is low, data passes from A inputs to Y outputs; when high, outputs enter high-impedance state. The ABT (Advanced BiCMOS Technology) architecture enables TTL-compatible input thresholds while operating from a 3.3-V supply.

It integrates I_off circuitry that disables outputs during power-down to prevent current backflow, and power-up 3-state logic that holds outputs high-Z during V_CC ramp-up. Absolute maximum ratings allow 5.5-V input tolerance and −0.5 V to 7 V output voltage range in high-Z state - critical for mixed-voltage system interoperability.

Key Specifications

Pinout & Package

SN74LVT244BDB uses a 20-pin SSOP (Shrink Small Outline Package) with 0.65 mm pitch, 7.4 mm × 5.3 mm body size, and 2.0 mm max height per JEDEC MO-150. Pin 1 index located at top-left corner with notch marking.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVTH244APW and 74ALVC244PW, SN74LVT244BDB uniquely combines 5-V input tolerance, 64 mA output drive, and I_off-enabled hot insertion - making it the only option among the three qualified for industrial backplane and live-module replacement scenarios.

Availability

SN74LVT244BDB is available at Aetrix Electronics and suitable for industrial backplane interface, memory expansion modules, hot-swappable I/O cards, and automotive diagnostic interfaces requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74LVT244BDB 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 connectivity technologies with over 90 years of innovation in industrial, automotive, and communications markets.

The SN74LVT244BDB belongs to TI's LVT (Low-Voltage BiCMOS Technology) logic family, engineered for high-speed, mixed-voltage system interconnect - specifically targeting 3.3-V core logic interfacing with legacy 5-V infrastructure.

FAQ

What is the maximum input voltage rating for SN74LVT244BDB?

The SN74LVT244BDB supports input voltages up to 5.5 V regardless of V_CC level, enabling direct connection to 5-V logic families without external clamping. This specification is explicitly defined in the Absolute Maximum Ratings table and verified under VI conditions with clamp-current compliance.

Does SN74LVT244BDB support hot insertion, and how is it implemented?

Yes, SN74LVT244BDB supports hot insertion via integrated I_off circuitry and power-up 3-state logic. When V_CC = 0 V, I_off disables outputs to prevent backflow current; during power-up, outputs remain in high-impedance state until V_CC stabilizes - both functions are documented in the Functional Description section of the datasheet.

What is the recommended pull-up resistor value for OE pins on SN74LVT244BDB?

Texas Instruments recommends tying OE pins to V_CC through a pull-up resistor with minimum value determined by the driver's current-sinking capability. For SN74LVT244BDB, a 10-kΩ resistor is typical; lower values (e.g., 4.7 kΩ) ensure faster disable timing but increase static current - design guidance appears in the "description/ordering information" section.

Can SN74LVT244BDB operate below 3.3 V, and what is the minimum functional supply voltage?

Yes, SN74LVT244BDB is fully specified from 2.7 V to 3.6 V. At 2.7 V, it maintains guaranteed VOL ≤ 0.5 V at I_OL = 24 mA and t_PLH/t_PHL ≤ 3.8 ns - enabling reliable operation in battery-powered systems with unregulated 2-cell Li-ion supplies.

Is SN74LVT244BDB pin-compatible with other packages of the same part number?

SN74LVT244BDB (SSOP-20) shares identical pinout and functionality with SN74LVT244BDW (SOIC-20), SN74LVT244BPW (TSSOP-20), and SN74LVT244BRGYR (VQFN-20); all variants use the same terminal assignment diagram and logic function - confirmed in the "terminal assignments" and "ordering information" sections of the datasheet.