Nexperia USA Inc. 74AHCT573D,112

Overview

74AHCT573D,112 from Nexperia is an octal D-type transparent latch with 3-state outputs, designed for bus interface and data buffering in 5 V TTL-level systems. It features independent latch enable (LE) and output enable (OE) controls, overvoltage-tolerant inputs up to 5.5 V, CMOS low-power operation, and operates across –40 °C to +125 °C. Used in microcontroller I/O expansion, memory address latching, and industrial control logic.

For engineers reviewing the 74AHCT573D,112 datasheet, 74AHCT573D,112 pinout, 74AHCT573D,112 application, or 74AHCT573D,112 equivalent, key selection criteria include TTL-compatible input thresholds (VIH = 2.0 V, VIL = 0.8 V), propagation delay ≤7.0 ns (VCC = 5 V, CL = 15 pF), 3-state output leakage <±0.25 μA, and SO20 package compatibility with legacy 74-series footprints.

Technical Context

This device implements eight independent D-latches with synchronous transparency controlled by a single active-HIGH LE input; data passes through when LE is HIGH and is captured on the HIGH-to-LOW transition. The common active-LOW OE input independently places all eight outputs into high-impedance state without affecting latch contents.

Input thresholds are TTL-compatible (VIH = 2.0 V min, VIL = 0.8 V max at VCC = 4.5–5.5 V), enabling direct interfacing with legacy 5 V logic families. Overvoltage tolerance (inputs rated to 5.5 V) supports mixed-voltage domain translation between 3.3 V and 5 V subsystems without level shifters.

Key Specifications

Pinout & Package

74AHCT573D,112 is supplied in SO20 (SOT163-1) plastic small outline package: 20-pin, 7.5 mm body width, 1.27 mm pitch, gull-wing leads. Pin 1 index located at top-left corner with notch or dot marking.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74AHC573D,112 and SN74HCT573PW, the 74AHCT573D,112 uniquely balances TTL compatibility, low static current (40 μA max), and robust overvoltage tolerance-making it optimal for cost-sensitive industrial controllers where 5 V logic dominance and supply margin are critical.

Availability

74AHCT573D,112 is available at Aetrix Electronics and suitable for industrial control systems, legacy microprocessor upgrades, and PLC I/O modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74AHCT573D,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, discrete, and MOSFET solutions with focus on efficiency, reliability, and sustainability.

The 74AHCT573 belongs to Nexperia's industry-standard 74-series logic family, engineered for robust interoperability in industrial, computing, and communications infrastructure where pin compatibility, wide temperature operation, and noise immunity are essential.

FAQ

What is the maximum clock frequency supported by the 74AHCT573D,112?

The 74AHCT573D,112 does not operate on a clock signal-it is edge-triggered by the latch enable (LE) input. Its usable data rate is determined by propagation delay (≤7.0 ns) and set-up/hold times (3.5 ns / 1.5 ns), supporting effective latch rates up to ~100 MHz in optimized layouts with 15 pF loads. Timing margins must account for board trace delays and input slew rates.

Can the 74AHCT573D,112 be used with a 3.3 V supply?

No-74AHCT573D,112 is specified only for 4.5 V to 5.5 V operation. Its TTL-compatible input thresholds require ≥4.5 V VCC to guarantee VIH ≥2.0 V and VIL ≤0.8 V. For 3.3 V systems, use the pin-compatible 74AHC573D,112, which supports 2.0–5.5 V and has CMOS input thresholds.

How does the overvoltage tolerance benefit system design?

Inputs tolerate up to 5.5 V regardless of VCC, allowing direct connection to 5 V buses even when powered from 3.3 V (using 74AHC573). This eliminates external level shifters or clamping diodes in mixed-voltage interfaces-reducing component count, board space, and signal integrity risks from added capacitance or propagation skew.

Is thermal derating required for continuous operation at +125 °C?

Yes-total power dissipation must be derated linearly above +109 °C for the SO20 (SOT163-1) package: Ptot decreases by 12.3 mW per °C above that point. At +125 °C, maximum allowed Ptot is 500 mW − (12.3 mW/K × 16 K) = 303 mW. Designers must verify junction temperature using θJA and actual power consumption under worst-case switching conditions.