Texas Instruments SN74LV245ATPWR

Overview

SN74LV245ATPWR from Texas Instruments is an octal bus transceiver with 3-state outputs, designed for asynchronous two-way data communication between A and B buses in 4.5–5.5 V systems. It features direction control (DIR), output enable (OE), TTL-compatible inputs, 3.5 ns typical propagation delay at 5 V, and Ioff support for partial-power-down mode.

For engineers reviewing the SN74LV245ATPWR datasheet, SN74LV245ATPWR pinout, SN74LV245ATPWR application, or SN74LV245ATPWR equivalent, key selection criteria include bidirectional bus isolation timing, 3-state output drive capability (±16 mA), mixed-mode voltage operation, ground bounce (VOLP < 0.8 V) and undershoot (VOHV > 2.3 V) performance, and TSSOP-20 package compatibility with industrial temperature range (–40°C to 125°C).

Technical Context

The SN74LV245ATPWR implements dual-control logic: DIR selects data flow direction (A→B or B→A), while OE independently enables or disables all eight channels into high-impedance state. Its CMOS input structure accepts TTL-level signals, and the Ioff circuitry actively blocks current backflow when VCC = 0 V.

Designed for mixed-voltage system interfacing, it supports 5-V operation with guaranteed VIH ≥ 2 V and VIL ≤ 0.8 V across –40°C to 125°C. Switching characteristics are specified at CL = 15 pF and CL = 50 pF, with tPLH/tPHL ≤ 9.7 ns (max) and enable/disable times (tPZH/tPLZ) ≤ 17.3 ns (max) under worst-case conditions.

Key Specifications

Pinout & Package

TSSOP-20 (PW) package: 6.5 mm × 4.4 mm, 0.65 mm pitch, 1.2 mm max height, exposed thermal pad optional, RoHS-compliant NIPDAU finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LV245ATPWR, SN74LVC245APW and 74ALVC245PW offer higher speed or drive but sacrifice 5-V compatibility and Ioff protection-making SN74LV245ATPWR the sole choice for mixed-voltage, hot-pluggable, or industrial-grade 5-V bus isolation.

Availability

SN74LV245ATPWR is available at Aetrix Electronics and suitable for industrial PLC backplanes, automotive body control modules, test equipment pattern generators, and medical imaging data acquisition boards requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SN74LV245ATPWR 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 solutions, with decades of experience in high-reliability logic and interface ICs.

The SN74LV245ATPWR belongs to TI's LV family of low-voltage, high-speed logic devices engineered for robust 5-V system interfacing, particularly in industrial automation, automotive electronics, and instrumentation where timing precision and power-domain isolation are critical.

FAQ

What is the maximum clock/data rate supported by the SN74LV245ATPWR?

The SN74LV245ATPWR does not operate on a clock; it is an asynchronous transceiver. Its 3.5 ns typical propagation delay at 5 V supports reliable data transfer up to ~140 MHz for single-bit edges, and practical parallel bus rates of 25–50 MHz depending on trace length, load capacitance, and noise margin. Timing is validated at CL = 15 pF and CL = 50 pF per the SCLS605D datasheet.

Can the SN74LV245ATPWR interface between 3.3-V and 5-V logic domains?

Yes - the SN74LV245ATPWR supports mixed-mode voltage operation on all ports. Its inputs accept TTL-compatible thresholds (VIH ≥ 2 V, VIL ≤ 0.8 V), allowing direct connection to 3.3-V outputs, while its outputs swing rail-to-rail (0 V to VCC) at 5 V, safely driving 5-V inputs. No external level shifters are needed when VCC = 5 V.

How should OE and DIR be biased during power-up to avoid bus contention?

To ensure high-impedance state at power-up, OE must be held high (via 10-kΩ pullup to VCC) until system initialization completes. DIR may float or be pulled to either rail; however, tying DIR to GND or VCC via 100-kΩ resistor prevents undefined direction during reset. The SN74LV245ATPWR datasheet explicitly recommends OE pullup for power sequencing safety.

Does the SN74LV245ATPWR require external decoupling capacitors?

Yes - a 0.1-μF ceramic capacitor must be placed as close as possible (≤5 mm) to the VCC pin (pin 20) and GND pin (pin 10) to suppress switching noise and maintain stable supply during fast output transitions. For systems with heavy bus loading, adding a 4.7-μF bulk capacitor nearby further improves transient response.

Is the TSSOP-20 package of SN74LV245ATPWR lead-free and RoHS compliant?

Yes - the SN74LV245ATPWR uses NiPdAu (NIPDAU) lead finish and is RoHS-compliant per TI's PACKAGE OPTION ADDENDUM. It carries MSL Level-1 rating (unlimited floor life at ≤30°C/60% RH) and is qualified for peak reflow temperatures up to 260°C, meeting IPC/JEDEC J-STD-020 standards.