NXP Semiconductors 74LVC544AD,112

Overview

74LVC544AD,112 from NXP Semiconductors is an octal registered inverting transceiver with dual-directional 3-state D-type latches, operating from 1.2 V to 3.6 V supply, supporting 5 V-tolerant I/O, and rated for −40 °C to +125 °C. It enables bidirectional data buffering with independent latch and output enable controls per direction, used in bus interface isolation between mixed-voltage subsystems.

For engineers reviewing the 74LVC544AD,112 datasheet, 74LVC544AD,112 pinout, 74LVC544AD,112 application, or 74LVC544AD,112 equivalent, key selection criteria include its 24-pin SO24 package, 3.3 ns typical propagation delay at 3.3 V, 5 V input tolerance, latch transparency control timing, and compliance with JEDEC JESD8-7A/5A/C standards.

Technical Context

The 74LVC544AD,112 implements two independent 8-bit register paths (A↔B), each with separate active-low latch enable (LEAB/LEBA) and output enable (OEAB/OEBA) inputs. Data flow direction is controlled by EAB/EBA enable signals, allowing concurrent A-to-B and B-to-A operation when both paths are enabled.

Each latch operates on a LOW-to-HIGH transition of its respective LE signal to capture data; outputs remain stable during hold mode. The device supports partial power-down (high-impedance I/O at VCC = 0 V) and meets HBM ESD >2000 V, ensuring robustness in industrial board-level environments.

Key Specifications

Pinout & Package

74LVC544AD,112 uses the SO24 plastic small outline package (SOT137-1), 24-lead, 7.5 mm body width, with standard 1.27 mm lead pitch and gull-wing leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74LVC544AD,112, SN74LVC544APWRE4 offers identical functionality in a smaller footprint but demands tighter assembly tolerances, while 74LVC544ADB,118 maintains compatibility with older SSOP layouts but sacrifices thermal performance in high-power-density applications.

Availability

74LVC544AD,112 is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, test equipment, and medical imaging systems requiring stable component supply across extended temperature ranges.

Supply support for 74LVC544AD,112 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 focused on secure connectivity solutions for automotive, industrial, and IoT applications, with deep expertise in logic, interface, and power management ICs.

The 74LVC544AD,112 belongs to NXP's LVC (Low-Voltage CMOS) logic family, designed specifically for mixed-voltage system interfacing with high noise immunity, low power, and wide supply range flexibility.

FAQ

What is the maximum operating frequency supported by the 74LVC544AD,112?

The 74LVC544AD,112 does not specify a clock frequency since it is an asynchronous registered transceiver. Its usable data rate is determined by propagation delay (6.5 ns max at 3.3 V) and setup/hold times (2.0 ns min). For reliable operation, the minimum pulse width on LEAB/LEBA must be ≥2.0 ns at 3.3 V, supporting effective data rates up to ~150 MHz in latch-controlled burst transfers.

Can the 74LVC544AD,112 be used with a 1.2 V supply voltage?

Yes, the 74LVC544AD,112 is fully specified down to 1.2 V supply voltage per Table 5. At 1.2 V, it maintains functional operation with VIH = 1.08 V and VOL ≤ 0.12 V, though propagation delay increases to 17 ns and output drive strength reduces. It remains compliant with JEDEC JESD8-7A for 1.65–1.95 V operation but functions correctly at the 1.2 V minimum.

Does the 74LVC544AD,112 support hot insertion or live bus swapping?

The 74LVC544AD,112 supports partial power-down: when VCC = 0 V, all I/O pins enter high-impedance state with IOFF ≤ ±20 μA, preventing back-driving of live buses. However, it lacks dedicated hot-swap protection circuitry (e.g., slew-rate control or current limiting), so external series resistors or dedicated hot-swap controllers are recommended for true live-insertion applications.

How does the inverting function of the 74LVC544AD,112 affect data integrity?

The 74LVC544AD,112 performs logical inversion on data passing through its latches - i.e., output = NOT(input). This is inherent to its design and documented in the functional description. To preserve data polarity, either invert signals externally before latching or use complementary logic in firmware. The inversion applies identically in both A→B and B→A directions and is consistent across all eight channels.

What is the thermal resistance (θJA) of the 74LVC544AD,112 in SO24 package?

The 74LVC544AD,112 in SO24 (SOT137-1) has a junction-to-ambient thermal resistance (θJA) of 70 °C/W, derived from its 500 mW maximum power dissipation rating and 70 °C derating threshold (8 mW/K above 70 °C). This value assumes standard JEDEC 2-layer board conditions; actual θJA depends on PCB copper area, airflow, and nearby heat sources.