Texas Instruments SN74LVT245DWR

Overview

SN74LVT245DWR from Texas Instruments is a 3.3-V ABT octal bus transceiver with 3-state outputs, designed for asynchronous bidirectional data transfer between 3.3-V and 5-V buses. It supports mixed-mode signal operation, hot insertion via Ioff and power-up 3-state, and operates down to 2.7 V. Key parameters include VCC = 2.7–3.6 V, tPLH/tPHL ≤ 3.5 ns at 3.3 V, and IOL = 64 mA.

For engineers reviewing the SN74LVT245DWR datasheet, SN74LVT245DWR pinout, SN74LVT245DWR application, or SN74LVT245DWR equivalent, this page delivers verified electrical specs, SOIC-20 pin mapping, hot-swap design guidance, and validated alternative parts for voltage-level translation in embedded bus interfaces.

Technical Context

The SN74LVT245DWR implements an advanced BiCMOS ABT (Advanced Bus Transceiver) architecture enabling TTL-compatible 5-V input/output signaling while powered by a 3.3-V supply. Its DIR and OE control logic allows real-time direction selection and bus isolation without timing constraints.

It integrates Ioff circuitry to block current backflow during power-down and power-up 3-state logic that forces outputs into high-impedance before VCC stabilizes-critical for live-insertion in backplane and modular systems. Latch-up immunity exceeds 100 mA per JESD 78 Class II.

Key Specifications

Pinout & Package

SN74LVT245DWR uses a 20-pin SOIC (DW) package measuring 7.5 mm × 12.8 mm with 1.27 mm pitch. Pin 1 is located at the top-left corner adjacent to the index mark.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVTH245PWRE4 and 74ALVC164245DGGR, the SN74LVT245DWR uniquely combines 64-mA drive, hot-insertion capability, and SOIC-20 compatibility - making it optimal for industrial backplanes requiring robustness and drop-in replaceability without layout changes.

Availability

SN74LVT245DWR is available at Aetrix Electronics and suitable for industrial PLC backplanes, embedded CPU-peripheral bridges, and modular test equipment requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant green packaging.

Supply support for SN74LVT245DWR 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 expertise in high-reliability interface ICs.

The SN74LVT245DWR belongs to TI's ABT logic family, engineered specifically for high-speed, mixed-voltage bus interfacing in industrial automation, communications infrastructure, and modular electronics where signal integrity and hot-swap resilience are critical.

FAQ

What is the maximum data rate supported by SN74LVT245DWR?

The SN74LVT245DWR has a typical propagation delay of 2.1–2.3 ns and maximum of 3.5 ns at VCC = 3.3 V, supporting reliable data rates up to approximately 140 Mbps in point-to-point bus configurations. Actual throughput depends on trace length, loading, and termination - for sustained 100-Mbps operation, maintain CL ≤ 50 pF and use controlled-impedance routing.

Does SN74LVT245DWR require external pull-up resistors on OE or DIR?

OE should be tied to VCC through a pull-up resistor (typically 4.7 kΩ–10 kΩ) to ensure high-impedance state during power-up; DIR may float only if direction is fixed externally. The SN74LVT245DWR does not integrate internal pull-ups, so external biasing is mandatory for robust startup behavior in systems with uncontrolled reset sequencing.

Can SN74LVT245DWR safely interface a 5-V microcontroller with a 3.3-V FPGA?

Yes - the SN74LVT245DWR accepts 5-V TTL inputs (VIH = 2.0 V min) while operating at 3.3-V VCC, and drives 3.3-V CMOS-compatible outputs (VOH ≥ 2.4 V at IOL = 24 mA). It is explicitly designed for this mixed-mode scenario, eliminating need for additional level-shifting circuitry when connecting legacy 5-V controllers to modern 3.3-V FPGAs.

Is SN74LVT245DWR pin-compatible with other packages in the SN74LVT245B family?

Yes - all SN74LVT245B variants including SN74LVT245BDWR, SN74LVT245BDBR, and SN74LVT245BPWR share identical 20-pin functional pinout and logic behavior. The SN74LVT245DWR (SOIC-DW) can be substituted with SSOP-DB or TSSOP-PW versions without PCB redesign, provided mechanical clearance and thermal constraints are met.

What thermal considerations apply to SN74LVT245DWR in continuous 64-mA output operation?

At maximum IOL = 64 mA per output and worst-case ambient, the SN74LVT245DWR in SOIC-DW package has θJA = 58°C/W. With 8 outputs sinking 64 mA simultaneously, power dissipation reaches ~270 mW, raising junction temperature by ~16°C above ambient. Maintain copper pour and avoid stacking heat-generating components nearby to stay within −40°C to +85°C operating range.