NXP Semiconductors 74LVT543D,118

Overview

74LVT543D,118 from NXP Semiconductors (formerly Philips) is a 3.3V octal latched transceiver with dual enable and 3-state outputs, combining bidirectional data latching and bus isolation in a single 24-pin SO package. It provides +64mA/–32mA drive capability, TTL-compatible I/O levels, and bus-hold inputs for 5V-tolerant system interfacing in high-speed digital backplanes and memory expansion modules.

For engineers reviewing the 74LVT543D,118 datasheet, 74LVT543D,118 pinout, 74LVT543D,118 application, or 74LVT543D,118 equivalent, key selection criteria include independent A↔B latch control, power-up 3-state behavior, 2.3 ns typical propagation delay at 3.3V, and JEDEC-compliant latch-up immunity exceeding 500mA.

Technical Context

The 74LVT543D,118 implements two independent sets of eight D-type latches-one for A-to-B and one for B-to-A data flow-each with dedicated Latch Enable (LEAB/LEBA), Enable (EAB/EBA), and Output Enable (OEAB/OEBA) inputs. This architecture enables simultaneous or asynchronous bidirectional latching without contention.

It operates within a 2.7V–3.6V supply range, supports 5V-tolerant inputs and outputs, and features bus-hold circuitry on all A-side data inputs to eliminate external pull-ups. Power-up reset ensures outputs enter high-impedance state before valid logic levels stabilize.

Key Specifications

Pinout & Package

74LVT543D,118 is housed in a 24-pin plastic small outline (SO) package (SOT137-1), 7.5 mm body width, surface-mount compatible with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVT8984DW and 74ALVT16543MTD, the 74LVT543D,118 offers optimal cost and footprint for 8-bit 3.3V↔5V bridging where only A-port bus-hold is required and space-constrained SO packaging is critical.

Availability

74LVT543D,118 is available at Aetrix Electronics and suitable for memory expansion interfaces, backplane data bridges, hot-swappable module adapters, and industrial I/O controller hubs requiring stable component supply across extended product lifecycles.

Supply support for 74LVT543D,118 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

NXP Semiconductors is a global semiconductor leader delivering high-performance logic, analog, and interface solutions for automotive, industrial, and communications markets.

The 74LVT543D,118 belongs to NXP's legacy LVT (Low-Voltage TTL) logic family, engineered for seamless interoperability between 3.3V and 5V systems in high-reliability embedded control and data acquisition platforms.

FAQ

What is the maximum operating temperature range for the 74LVT543D,118?

The 74LVT543D,118 is rated for operation from –40°C to +85°C, meeting industrial-grade thermal requirements. This range is validated per the manufacturer's recommended operating conditions and applies to all specified DC and AC electrical characteristics, including propagation delay, output drive, and bus-hold functionality. The device maintains full performance across this range without derating.

Does the 74LVT543D,118 support live insertion and extraction?

Yes, the 74LVT543D,118 explicitly supports live insertion and extraction per its datasheet features. This capability relies on three design elements: power-up 3-state behavior (outputs remain high-impedance until VCC stabilizes), bus-hold inputs on the A port (preventing floating states during partial connection), and controlled output disable timing (tPHZ/tPLZ ≤ 7.1 ns). These ensure no bus contention or signal corruption occurs during hot-swap events in modular backplane systems.

What is the purpose of the bus-hold feature on the 74LVT543D,118 A-port inputs?

The bus-hold feature on the A0–A7 inputs of the 74LVT543D,118 maintains a valid logic state (high or low) when those inputs are left unconnected or disconnected, eliminating the need for external pull-up or pull-down resistors. It draws ±75 µA of overdrive current to hold the line, ensuring stable operation during system initialization, cable disconnection, or sensor failure. This function is not present on the B-port inputs.

Can the 74LVT543D,118 interface directly with 5V logic systems?

Yes, the 74LVT543D,118 can interface directly with 5V logic systems. Its inputs tolerate up to 5.5V regardless of VCC, and its outputs drive 5V buses with guaranteed VOH ≥ 2.4V and VOL ≤ 0.5V under load. The device achieves this while operating from a 3.3V supply, making it ideal for upgrading legacy 5V designs without adding level-shifters or dual-supply circuitry.

How does the latch enable (LE) and output enable (OE) logic interact in the 74LVT543D,118?

In the 74LVT543D,118, LEAB and OEAB operate independently: LEAB controls whether data flows transparently from A to B or is latched, while OEAB determines whether the B outputs are active or in high-impedance state. For example, with LEAB low and OEAB low, the A→B path is transparent and outputs reflect A inputs; with LEAB high and OEAB low, the last captured A data is held and displayed; with OEAB high, B outputs go high-Z regardless of LEAB state. This separation enables precise timing control in synchronous bus protocols.