Texas Instruments SN74LVTR245DW

Overview

SN74LVTR245DW from Texas Instruments is a 3.3-V Advanced BiCMOS Technology (ABT) octal bus transceiver with 3-state outputs, designed for bidirectional asynchronous data transfer between 3.3-V and 5-V buses. It features bus-hold inputs, direction control (DIR), output enable (OE), A-port undershoot reduction, and operates from 2.7 V to 3.6 V. Used in mixed-voltage system interfacing such as FPGA-to-microcontroller I/O bridging.

For engineers reviewing the SN74LVTR245DW datasheet, SN74LVTR245DW pinout, SN74LVTR245DW application, or SN74LVTR245DW equivalent, key selection criteria include 3.3-V VCC compatibility with 5-V tolerant I/O, ±64 mA B-port drive capability, bus-hold functionality eliminating external pullups, and DW package thermal performance (0.85 W at 55°C).

Technical Context

The SN74LVTR245DW implements dual-octet bidirectional data routing controlled by DIR and OE signals: DIR = L enables B→A transmission; DIR = H enables A→B transmission; OE = H forces all outputs into high-impedance state. Its ABT process delivers low static power (0.13–0.19 mA in disabled state) while supporting TTL-level signaling across voltage domains.

Bus-hold circuitry actively maintains valid logic levels on floating A/B port inputs without external resistors, and the A-port's reduced-output structure minimizes VOHV (voltage overshoot) during simultaneous switching. Absolute maximum ratings include VI up to 7 V and VCC up to 4.6 V, enabling robust operation in unregulated battery environments down to 2.7 V.

Key Specifications

Pinout & Package

SN74LVTR245DW uses a 20-pin plastic small-outline (DW) package with 300-mil body width, JEDEC MS-013 compliant, and 0.65 mm lead pitch. Thermal resistance θJA = 100°C/W (typ), rated for 0.85 W max power dissipation at TA = 55°C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC245A and SN74ALVC245, the SN74LVTR245DW uniquely combines 5-V output drive, bus-hold, and A-port undershoot suppression in a single 20-pin DW package-making it optimal for ruggedized mixed-voltage interconnects where layout constraints prevent external components.

Availability

SN74LVTR245DW is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, and test equipment requiring stable component supply, long-term lifecycle continuity, and verified 3.3-V/5-V interoperability.

Supply support for SN74LVTR245DW 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 over 50 years of innovation in industrial, automotive, and communications markets.

The SN74LVTR245DW belongs to TI's ABT logic family, engineered for mixed-signal system integration where 3.3-V core logic must reliably interface with legacy 5-V peripherals without external translation circuitry.

FAQ

What is the maximum supply voltage the SN74LVTR245DW can tolerate?

The SN74LVTR245DW has an absolute maximum VCC rating of 4.6 V. Operation beyond 3.6 V is not recommended for functional reliability, but the device withstands transient overvoltage up to 4.6 V without permanent damage. For sustained operation, maintain VCC within 2.7 V to 3.6 V per recommended conditions. The SN74LVTR245DW's robust design ensures safe handling of battery-sourced supply ripple common in portable industrial tools.

Does the SN74LVTR245DW support true 5-V output drive?

Yes, the SN74LVTR245DW B-port delivers up to 64 mA sink current and maintains VOH ≥ 2.0 V at IOL = 64 mA with VCC = 3.3 V, enabling direct interface with standard 5-V TTL loads. Its 5-V input tolerance (VI up to 7 V) and bus-hold inputs further ensure compatibility without external level shifters. This makes the SN74LVTR245DW ideal for bridging 3.3-V controllers to 5-V peripheral buses.

How does bus-hold functionality work on the SN74LVTR245DW?

The SN74LVTR245DW integrates active bus-hold circuitry on all A and B port inputs, providing ±75 µA holding current at VI = 0.8 V or 2.0 V. This maintains floating inputs at valid logic levels without external resistors, preventing metastability in unterminated or sparsely loaded buses. Bus-hold remains active regardless of OE or DIR state, ensuring deterministic behavior during power-up, reset, or hot-swap events involving the SN74LVTR245DW.

What is the thermal performance of the SN74LVTR245DW in its DW package?

The SN74LVTR245DW in the 20-pin DW package has a typical junction-to-ambient thermal resistance (θJA) of 100°C/W and a maximum power dissipation rating of 0.85 W at TA = 55°C. This allows reliable operation in industrial enclosures without forced airflow, provided board layout includes adequate copper pour under the exposed pad (if present) and minimal adjacent heat sources. Derating is required above 55°C ambient per the SN74LVTR245DW's thermal characteristics table.

Can the SN74LVTR245DW be used in battery-powered devices with variable supply voltage?

Yes, the SN74LVTR245DW supports unregulated battery operation from 2.7 V to 3.6 V, making it suitable for single-cell Li-ion (3.0–3.6 V) or two-cell alkaline (2.7–3.2 V) systems. Its ABT process ensures stable propagation delay (<5 ns) and output drive across this range, and bus-hold functionality remains effective even at minimum VCC. This capability is explicitly validated in the SN74LVTR245DW datasheet's recommended operating conditions table.