NXP Semiconductors 74LVC573AD,112

Overview

74LVC573AD from Nexperia is an octal D-type transparent latch with 3-state outputs, 5 V tolerant I/O, and IOFF partial power-down capability. It operates from 1.2 V to 3.6 V supply, supports mixed-voltage translation between 3.3 V and 5 V systems, and features Schmitt-trigger inputs for noise immunity. Used in bus interface and data buffering applications requiring level-shifting and output isolation.

For engineers reviewing the 74LVC573AD datasheet, 74LVC573AD pinout, 74LVC573AD application, or 74LVC573AD equivalent, this device serves as a voltage-tolerant, low-power latching buffer with precise timing control (tpd ≤ 6.2 ns at 3.3 V), high-impedance enable/disable (ten/tdis ≤ 9.5 ns), and robust ESD protection (HBM > 2000 V).

Technical Context

The 74LVC573AD implements eight independent D-latches controlled by a shared active-HIGH latch enable (LE) and active-LOW output enable (OE). When LE is HIGH, Qn follows Dn in transparent mode; when LE goes LOW, data is latched and held regardless of subsequent Dn changes. OE independently controls 3-state output drivers without affecting latch state.

Its IOFF circuitry disables outputs and blocks backflow current when VCC = 0 V, enabling safe hot-insertion in partial power-down systems. Input overvoltage tolerance up to 5.5 V-combined with Schmitt-trigger inputs-ensures reliable operation across noisy or slow-rising signals in mixed-supply environments.

Key Specifications

Pinout & Package

74LVC573AD is supplied in SO20 (SOT163-1) package: plastic small outline, 20-pin, 7.5 mm body width, standard JEDEC footprint compatible with automated assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC573APW and 74LVC573ABQ, the 74LVC573AD (SO20) provides the highest mechanical robustness and easiest hand-soldering/rework compatibility, making it optimal for prototyping, field-serviceable equipment, and industrial control panels requiring long-term serviceability.

Availability

74LVC573AD is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, automotive body control modules, test equipment digital pattern generation, and industrial motor drive controllers requiring stable component supply across extended temperature ranges and mixed-voltage interfaces.

Supply support for 74LVC573AD 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

Nexperia is a global semiconductor expert focused on high-volume, high-reliability logic, discrete, and MOSFET solutions for industrial, automotive, and computing markets.

The 74LVC573A series belongs to Nexperia's advanced LVC logic family, designed specifically for low-voltage, mixed-supply system interfacing with emphasis on voltage tolerance, power-down safety, and JEDEC compliance.

FAQ

Can 74LVC573AD operate with VCC = 1.2 V while accepting 5 V inputs?

Yes. The device is fully specified down to 1.2 V supply and supports input voltages up to 5.5 V regardless of VCC level. At VCC = 1.2 V, VIH is guaranteed ≥ 1.08 V and VIL ≤ 0.12 V, ensuring correct logic interpretation of 5 V signals without damage or undefined behavior.

What happens to outputs when VCC is powered off but 5 V remains on inputs or outputs?

The IOFF circuit automatically disables all outputs and blocks reverse current flow when VCC = 0 V, even if 5 V is present on Dn, Qn, or OE/LE pins. Output leakage is limited to ±10 μA, preventing damage to upstream/downstream devices during power sequencing or hot-swap events.

Is the 74LVC573AD pinout compatible with older 74HC573 or 74LS373 devices?

No. While functionally similar, the 74LVC573AD uses a flow-through pinout (D0–D7 on pins 2–9, Q0–Q7 on pins 12–19), whereas 74HC573 places Q0–Q7 on pins 2–9 and D0–D7 on pins 12–19 - a mirrored layout. Direct replacement requires PCB redesign or adapter board.

Does the device support simultaneous latching of all 8 bits on a single LE edge?

Yes. All eight latches share a common LE input and respond synchronously to its HIGH-to-LOW transition. Setup time (tsu = 1.7 ns min at 3.3 V) and hold time (th = 1.4 ns min) are guaranteed across all Dn inputs, ensuring deterministic, glitch-free parallel data capture without skew-induced metastability.