Texas Instruments SN74LVTH244AQPWREP

Overview

SN74LVTH244AQPWREP from Texas Instruments is an octal noninverting buffer/line driver with 3-state outputs, designed for 3.3-V V_CC operation while supporting 5-V TTL input/output interfaces. It features dual 4-bit channels, independent output-enable (OE) controls, bus-hold circuitry on all data inputs, and I_off/power-up 3-state for hot-insertion in backplane or modular systems. Used in industrial control backplanes and mixed-voltage FPGA I/O bridging.

For engineers reviewing the SN74LVTH244AQPWREP datasheet, SN74LVTH244AQPWREP pinout, SN74LVTH244AQPWREP application, or SN74LVTH244AQPWREP equivalent, key selection criteria include its −40°C to 125°C extended temperature rating, 2.7-V to 3.6-V supply range, 32-mA low-level output drive, bus-hold functionality eliminating external resistors, and TSSOP-20 package compatibility with high-density PCB layouts.

Technical Context

This device implements two independent 4-bit noninverting buffers, each with dedicated OE control (1OE and 2OE), enabling selective channel enablement in shared-bus architectures. All eight data inputs feature active bus-hold circuitry, maintaining valid logic states without external pullup/pulldown resistors.

It supports mixed-mode signal operation: 5-V-tolerant inputs and outputs while powered from a 3.3-V supply, with I_off protection disabling outputs during power-down to prevent current backflow. Power-up 3-state ensures outputs remain high-impedance until V_CC stabilizes, avoiding bus contention.

Key Specifications

Pinout & Package

TSSOP-20 (PW) package: 6.5 mm × 4.4 mm body, 0.65 mm pitch, 1.2 mm max height, lead-free NiPdAu finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC244APWR, SN74LVTH244AQPWREP adds bus-hold and 125°C qualification at minimal cost premium; versus SN74LVCH244AQPWREP, it trades Schmitt-trigger input noise immunity for slightly lower input capacitance (3 pF vs. 4.5 pF), benefiting high-speed edge rates.

Availability

SN74LVTH244AQPWREP is available at Aetrix Electronics and suitable for industrial automation backplanes, automotive body control modules, and FPGA-based test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74LVTH244AQPWREP 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 heritage in high-reliability interface and power management ICs.

The SN74LVTH244AQPWREP belongs to TI's enhanced-product (EP) logic family, engineered for mission-critical industrial and automotive applications demanding extended temperature operation, controlled baseline manufacturing, and full DMS support.

FAQ

What is the maximum input voltage tolerance for SN74LVTH244AQPWREP?

The SN74LVTH244AQPWREP supports input voltages up to 5.5 V regardless of V_CC level, enabling direct connection to 5-V logic families without external level-shifting circuitry. This 5-V tolerance applies to all data (A) and control (OE) inputs, and is validated across the full −40°C to 125°C operating range. The absolute maximum rating is 7 V, but functional operation is guaranteed only up to 5.5 V per the recommended operating conditions table in the SCAS691C datasheet.

Does SN74LVTH244AQPWREP require external pull-up resistors on its inputs?

No, SN74LVTH244AQPWREP does not require external pull-up or pull-down resistors on its data inputs (1A1–1A4, 2A1–2A4) because it integrates active bus-hold circuitry that maintains valid logic states on unused or floating inputs. Using external resistors with the bus-hold feature is explicitly discouraged in the datasheet, as it may cause contention or increased power consumption. Only the OE pins should be pulled high via a resistor during power-up to ensure safe 3-state behavior.

Can SN74LVTH244AQPWREP be used in hot-swap applications?

Yes, SN74LVTH244AQPWREP is explicitly designed for hot-insertion applications via dual protection mechanisms: I_off circuitry disables outputs when V_CC = 0 V to prevent back-current flow, and power-up 3-state holds outputs in high-impedance during power ramp-up. These features are qualified per JEDEC standards and documented in the SCAS691C datasheet, making SN74LVTH244AQPWREP suitable for modular backplanes, pluggable I/O cards, and telecom line cards where live insertion/removal is required.

What is the thermal performance of SN74LVTH244AQPWREP in its TSSOP-20 package?

The SN74LVTH244AQPWREP in the TSSOP-20 (PW) package has a junction-to-ambient thermal resistance (θ_JA) of 83°C/W under standard JEDEC test conditions. This value assumes a 1-inch² copper pad with two vias; actual board layout significantly impacts thermal performance. At maximum rated load (32 mA per output, all eight outputs active), power dissipation remains below 100 mW, keeping junction temperature well within limits even at 125°C ambient - provided adequate PCB copper area is allocated per TI's thermal design guidelines.

How does the bus-hold feature of SN74LVTH244AQPWREP improve system reliability?

The bus-hold feature in SN74LVTH244AQPWREP actively maintains the last-valid logic state on each data input (1A1–1A4, 2A1–2A4) when the driving source is disconnected or inactive, preventing undefined floating states that could trigger spurious transitions or increased dynamic power in downstream logic. This eliminates susceptibility to EMI-induced glitches and removes dependency on external biasing components, directly improving functional safety and long-term reliability in harsh industrial or automotive environments where connector wear or intermittent connections occur.