Texas Instruments SN74LVTH543PWRE4

Overview

SN74LVTH543PWRE4 from Texas Instruments is an octal transceiver with dual-directional latched data flow, supporting mixed-mode 3.3-V VCC operation while interfacing to 5-V TTL systems. It features bus-hold on all data inputs, Ioff and power-up 3-state for hot insertion, and operates down to 2.7 V for unregulated battery applications.

For engineers reviewing the SN74LVTH543PWRE4 datasheet, SN74LVTH543PWRE4 pinout, SN74LVTH543PWRE4 application, or SN74LVTH543PWRE4 equivalent, key selection factors include its 24-pin TSSOP package, bidirectional latch-enable and output-enable control per direction, bus-hold elimination of external resistors, and guaranteed hot-insertion support via Ioff and power-up 3-state.

Technical Context

The SN74LVTH543PWRE4 integrates two independent sets of D-type latches-one for A-to-B and one for B-to-A data flow-each with dedicated CE, LE, and OE controls. Its bus-hold circuitry actively maintains valid logic states on undriven A/B inputs without external pullups.

It supports true mixed-signal interfacing: 5-V-tolerant inputs and outputs while powered from a 3.3-V supply, with absolute maximum input voltage up to 7 V and output drive capability of ±64 mA (IOL/IOH) at VCC = 3 V. The device enters high-impedance during power-up/down when VCC is between 0 and 1.5 V, and requires OE tied to VCC via pullup above that threshold for guaranteed Hi-Z.

Key Specifications

Pinout & Package

TSSOP-24 (PW) package: 4.4 mm × 5.0 mm body, 0.65 mm pitch, 1.2 mm max height, exposed metal pad not electrically connected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC543APWRE4 and 74ALVCH162245DGGR, the SN74LVTH543PWRE4 uniquely combines 5-V-tolerant I/O, integrated bus-hold, latch functionality, and hot-insertion support in a 24-pin TSSOP - making it the only option among the three for robust, self-contained mixed-voltage data bridging with storage.

Availability

SN74LVTH543PWRE4 is available at Aetrix Electronics and suitable for industrial PLC backplane interfaces, automotive body control modules, medical patient monitor data aggregation, and test equipment digital pattern generation requiring stable component supply and long-term production continuity.

Supply support for SN74LVTH543PWRE4 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 technologies, with over 50 years of innovation in industrial, automotive, and communications markets.

The SN74LVTH543PWRE4 belongs to TI's LVTH logic family, designed specifically for robust mixed-voltage system interfacing in harsh environments where reliability, hot-swap capability, and bus stability are critical.

FAQ

What is the function of the CEAB and CEBA pins on the SN74LVTH543PWRE4?

The CEAB (Chip Enable A-to-B) and CEBA (Chip Enable B-to-A) pins act as master enables for each data direction. When CEAB is low, the A-to-B path is activated - allowing data to pass from A inputs to B outputs when LEAB and OEAB are properly asserted. Similarly, CEBA must be low to enable B-to-A data flow. Both pins must be high to disable their respective paths entirely, placing associated outputs in high-impedance regardless of other controls. This dual-enable architecture prevents bus contention in shared-bus topologies.

Does the SN74LVTH543PWRE4 require external pullup resistors on its A/B data lines?

No, the SN74LVTH543PWRE4 does not require external pullup or pulldown resistors on its A1–A8 or B1–B8 data lines because it includes active bus-hold circuitry on all those inputs. This internal feature maintains a valid logic state (high or low) on unused or undriven inputs, eliminating floating nodes. Using external resistors with bus-hold enabled is explicitly discouraged in the datasheet as it may cause excessive current draw or logic instability.

Can the SN74LVTH543PWRE4 operate safely during hot insertion into a live 5-V backplane?

Yes, the SN74LVTH543PWRE4 is fully specified for hot-insertion applications. Its Ioff circuitry disables outputs when VCC = 0 V, preventing damaging current backflow from live 5-V buses into the unpowered device. Additionally, its power-up 3-state function ensures outputs remain in high-impedance during power ramp-up and ramp-down, avoiding bus conflicts. These features meet JEDEC JESD78 and JESD89 requirements for live-insertion reliability.

What is the maximum data rate supported by the SN74LVTH543PWRE4 in a typical application?

The SN74LVTH543PWRE4 supports data rates up to approximately 200 Mbps in point-to-point configurations, based on its typical propagation delay of 2.5 ns (tPLH/tPHL at VCC = 3.3 V, CL = 50 pF) and setup/hold times as low as 0.2 ns. Real-world throughput depends on bus loading, trace length, and noise margin - but the device is routinely used in 100-MHz synchronous bus interfaces where latch-enable timing aligns with system clocks. For sustained high-speed operation, proper PCB layout and local VCC decoupling are essential.

Is the SN74LVTH543PWRE4 pin-compatible with other packages of the same part number?

Yes, the SN74LVTH543PWRE4 shares identical pinout and electrical functionality with other package variants of the SN74LVTH543, including DW (SOIC), DB (SSOP), and DGV (TVSOP). All versions use the same 24-pin topology with identical signal assignments (e.g., Pin 1 = A1, Pin 13 = GND, Pin 14 = VCC). This allows drop-in replacement across packages for prototyping (TSSOP), volume production (SOIC), or space-constrained designs (TVSOP), provided mechanical clearances and thermal requirements are verified per package.