NXP Semiconductors 74LVC573APW,112

Overview

74LVC573APW,112 from Nexperia is an octal D-type transparent latch with 3-state outputs, latch enable (LE) and output enable (OE) controls, 1.2 V to 3.6 V supply operation, 5.5 V overvoltage-tolerant inputs/outputs, and Schmitt-trigger inputs for noise immunity - used in bus interface and level translation between 3.3 V and 5 V domains in industrial control backplanes.

For engineers reviewing the 74LVC573APW,112 datasheet, 74LVC573APW,112 pinout, 74LVC573APW,112 application, or 74LVC573APW,112 equivalent, this device serves as a bidirectional 8-bit data latch with IOFF-enabled partial power-down protection, high-impedance isolation during power sequencing, and JEDEC-compliant voltage-level interoperability across mixed-supply systems.

Technical Context

The 74LVC573APW implements eight independent D-type latches with synchronous transparent mode (LE HIGH) and stored mode (LE LOW), where data is captured on the HIGH-to-LOW transition of LE. Output state is fully decoupled from OE: asserting OE LOW disables all Qn outputs into high-impedance without affecting internal latch states.

Its IOFF circuitry actively disables outputs when VCC = 0 V, blocking backflow current during hot-insertion or partial system power-down. Schmitt-trigger inputs ensure robust operation with slow-rising signals up to 20 ns/V (at VCC = 1.65 V), and input tolerance to 5.5 V enables direct interfacing with legacy 5 V TTL logic without external level shifters.

Key Specifications

Pinout & Package

TSSOP20 package (SOT360-1): 20-pin thin shrink small outline, 4.4 mm body width, 0.65 mm pitch, exposed pad not electrically connected - optimized for high-density PCB layouts with improved thermal dissipation vs. SO20.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC573AQPWRQ1, the 74LVC573APW,112 offers identical performance at lower cost and lead time for industrial use, while the 74LVCH573A,118 adds bus-hold functionality at the expense of slightly higher ICC - making it preferable only where input floating is unavoidable.

Availability

74LVC573APW,112 is available at Aetrix Electronics and suitable for industrial PLC backplanes, memory subsystems in embedded controllers, and mixed-voltage I/O interfaces requiring stable component supply across long production lifecycles.

Supply support for 74LVC573APW,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

Nexperia is a global semiconductor expert delivering high-performance logic, analog, and MOSFET solutions with focus on efficiency, reliability, and sustainability - headquartered in Nijmegen, Netherlands.

The 74LVC573A belongs to Nexperia's advanced LVC logic family, engineered for low-voltage operation, mixed-supply interoperability, and robustness in harsh industrial environments - targeting bus buffering, address latching, and level translation.

FAQ

Can 74LVC573APW,112 operate with VCC = 1.2 V while driving 5 V-tolerant loads?

Yes - the device functions correctly at VCC = 1.2 V with guaranteed VIH/VIL thresholds and 5.5 V input tolerance. However, output drive strength drops to ±4 mA (typical), limiting fan-out to low-capacitance loads (<20 pF) and requiring careful signal integrity analysis for edge rates.

What happens to latch states when OE is asserted LOW and VCC is removed?

Latch states remain preserved in CMOS storage nodes even with VCC = 0 V and OE = LOW. The IOFF circuit blocks output current, but internal node voltages decay slowly due to leakage; retention time exceeds 100 ms at room temperature, sufficient for controlled power-down sequences.

Is the exposed thermal pad on SOT360-1 (TSSOP20) electrically connected?

No - the exposed pad on the 74LVC573APW,112's SOT360-1 package is not electrically connected to any internal node. It may be left floating or tied to GND for thermal improvement, but soldering it to GND requires a thermally isolated land to avoid shorting adjacent pins.

How does Schmitt-trigger input action improve noise immunity?

Schmitt-trigger inputs provide hysteresis (typically 0.3–0.5 V) between rising and falling thresholds, rejecting noise spikes ≤300 mV amplitude and enabling reliable operation with slow-rising signals (e.g., from mechanical switches or long cables) without external RC filtering.