Texas Instruments SN74LVTH244AGQNR

Overview

SN74LVTH244AGQNR 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 bus-hold on all data inputs, I_off and power-up 3-state for hot insertion, and supports unregulated battery operation down to 2.7 V. Used in industrial backplane interfaces and legacy 5-V system bridging.

For engineers reviewing the SN74LVTH244AGQNR datasheet, SN74LVTH244AGQNR pinout, SN74LVTH244AGQNR application, or SN74LVTH244AGQNR equivalent, key selection criteria include its 20-pin VFBGA (GQN) package, ±100 µA I_off at V_CC = 0 V, 3.3-V supply compatibility with 5-V tolerant I/O, and guaranteed t_PZH/t_PZL ≤ 5.3 ns at V_CC = 3.3 V.

Technical Context

This device implements two independent 4-bit noninverting buffers, each with dedicated output-enable (OE) control. Its ABT (Advanced BiCMOS Technology) architecture delivers TTL-compatible output drive while operating from a 3.3-V supply, enabling seamless interfacing between 3.3-V logic domains and legacy 5-V systems without level shifters.

The integrated bus-hold circuitry actively maintains valid logic states on floating inputs (±750 µA hold current), eliminating external pullup/pulldown resistors. I_off protection disables outputs during power-down to prevent backflow current, and power-up 3-state ensures high-impedance outputs during supply ramping.

Key Specifications

Pinout & Package

The SN74LVTH244AGQNR uses a 20-pin Very Thin Fine-Pitch Ball Grid Array (VFBGA) package designated GQN, measuring 3.5 mm × 4.5 mm with 0.5-mm pitch and an exposed thermal pad. Pin 1 is located at the top-left corner of the package, marked by a chamfered corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC244APWR and SN74ALVC244PWR, the SN74LVTH244AGQNR uniquely combines 5-V I/O tolerance, integrated bus-hold, and I_off-based hot-swap safety-making it the only option among the three qualified for mixed-voltage industrial backplanes requiring zero external biasing and live insertion.

Availability

SN74LVTH244AGQNR is available at Aetrix Electronics and suitable for industrial backplane interfaces, legacy system bus bridging, hot-swappable module control, and automated test equipment signal conditioning requiring stable component supply and long-term lifecycle assurance.

Supply support for SN74LVTH244AGQNR 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 delivering analog and embedded processing solutions, with deep expertise in logic, interface, and power management ICs.

The SN74LVTH244A product line was engineered for robust 3.3-V-to-5-V system interfacing in industrial, telecom, and test equipment-prioritizing mixed-voltage tolerance, bus stability, and hot-plug reliability over raw speed.

FAQ

What is the recommended power-up sequence for SN74LVTH244AGQNR to ensure safe 3-state initialization?

TI specifies that OE pins should be tied to V_CC through a pullup resistor during power-up to guarantee high-impedance outputs before internal logic stabilizes. For SN74LVTH244AGQNR, a 10-kΩ resistor is sufficient given its ±100-µA I_off and power-up 3-state circuitry, preventing bus conflicts in multi-device systems. This behavior is intrinsic to the SN74LVTH244AGQNR design and does not require external sequencing controllers.

Does SN74LVTH244AGQNR support true 5-V output drive, or is it limited to 5-V input tolerance?

The SN74LVTH244AGQNR supports 5-V input voltage tolerance but outputs swing only to V_CC (3.3 V) in the high state-not full 5 V. Its VOH is specified at ≥2.0 V (min) under 32-mA load, meeting TTL input thresholds but not 5-V CMOS levels. The device's value lies in receiving 5-V signals safely while driving 3.3-V–compatible loads, making it ideal for bridging-not replacing-5-V drivers. This behavior is confirmed in the SCAS586J datasheet Section 5.

Can bus-hold functionality be disabled on SN74LVTH244AGQNR to reduce input leakage or power consumption?

No-bus-hold is permanently enabled on SN74LVTH244AGQNR and cannot be disabled via configuration or external control. It draws ±750 µA dynamic hold current (per input) when transitioning, but static II(hold) remains below ±1 µA at steady-state logic levels. TI explicitly warns against using pullup/pulldown resistors with bus-hold, as they conflict with the internal circuitry. This fixed feature is integral to the SN74LVTH244AGQNR's design for eliminating external bias components.

What is the maximum capacitive load SN74LVTH244AGQNR can drive while maintaining guaranteed timing specs?

The SN74LVTH244AGQNR's switching characteristics (t_PLH, t_PHL, etc.) are characterized at CL = 50 pF, as stated in Section 6 of the SCAS586J datasheet. While it can physically drive higher capacitance, timing margins degrade beyond this value-e.g., t_PLH increases from 2.3 ns (typ) at 50 pF to ~4.1 ns at 100 pF. For designs requiring strict sub-4-ns propagation, keep total net capacitance ≤50 pF, including trace, via, and receiver input capacitance. This limit applies directly to SN74LVTH244AGQNR in real-world routing.

Is SN74LVTH244AGQNR pin-compatible with other packages in the SN74LVTH244A family, such as DW or PW?

No-SN74LVTH244AGQNR uses a 20-ball VFBGA (GQN) package with a unique 3.5 mm × 4.5 mm footprint and bottom-side ball layout, whereas DW (SOIC), PW (TSSOP), and DB (SSOP) packages use 20-pin gull-wing leaded formats with different pinouts and mechanical dimensions. Although all share identical logic functionality and signal naming, PCB redesign is required to migrate from leaded packages to SN74LVTH244AGQNR. This incompatibility is documented in TI's package drawings DB0020A, PW0020A, and RGY0020A.