Nexperia USA Inc. 74AHCT573BQ,115

Overview

74AHCT573BQ,115 from Nexperia is an octal D-type transparent latch with 3-state outputs, designed for bus-oriented bidirectional data latching 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, and operates across –40 °C to +125 °C. Key confirmed parameters: propagation delay ≤7.0 ns (VCC = 5 V, CL = 15 pF), supply range 4.5–5.5 V, input threshold VIH = 2.0 V (TTL-compatible), and 20-terminal DHVQFN package.

For engineers reviewing the 74AHCT573BQ,115 datasheet, 74AHCT573BQ,115 pinout, 74AHCT573BQ,115 application, or 74AHCT573BQ,115 equivalent, this device serves as a high-speed, low-power, temperature-robust latch for microcontroller address/data bus isolation, memory interface buffering, and industrial I/O expansion where TTL-level compatibility and 3-state bus control are required.

Technical Context

This device implements eight independent D-type latches with synchronous transparency controlled by LE, and a shared active-low OE that places all Q outputs in high-impedance state without affecting internal latch states. Its TTL-compatible input thresholds (VIH = 2.0 V, VIL = 0.8 V at VCC = 4.5–5.5 V) ensure reliable interfacing with legacy 5 V logic families.

Dynamic operation is characterized by sub-10 ns propagation delays (tpd ≤ 7.0 ns typical at 5 V/15 pF), 3.5 ns minimum data setup time (tsu), and 1.5 ns hold time (th), enabling stable operation in high-speed digital systems up to ~100 MHz clock-equivalent edge rates. The DHVQFN20 package provides thermal enhancement and board-space efficiency for dense PCB layouts.

Key Specifications

Pinout & Package

DHVQFN20 package (SOT764-1): 2.5 × 4.5 × 0.85 mm body, no leads, thermally enhanced exposed pad (GND-connected per datasheet recommendation), 20 terminals, pin 1 index marked on top surface.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74AHCT373BQ,115, this part offers identical functionality with no trade-offs; versus SN74HCT573PWR, it delivers better thermal performance and smaller footprint-critical for compact, high-temperature industrial PCBs.

Availability

74AHCT573BQ,115 is available at Aetrix Electronics and suitable for microcontroller bus isolation, memory interface buffering, and industrial I/O expansion requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74AHCT573BQ,115 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 optimized for efficiency, reliability, and miniaturization in industrial, automotive, and computing applications.

This device belongs to Nexperia's 74AHCT logic family, engineered specifically for robust 5 V TTL-compatible interfacing in demanding environments where signal integrity, wide temperature operation, and low power are essential.

FAQ

What is the maximum clock frequency supported by the 74AHCT573BQ,115?

The 74AHCT573BQ,115 does not operate on a clock signal-it is a transparent latch controlled by LE and OE. Its usable edge rate is determined by propagation delay (≤7.0 ns typical) and setup/hold times (3.5 ns tsu, 1.5 ns th), supporting reliable operation in bus systems with ≤100 MHz effective toggle rates under proper load conditions.

Can the 74AHCT573BQ,115 be used with a 3.3 V supply?

No-the 74AHCT573 variant is specified only for 4.5 V to 5.5 V operation. For 3.3 V systems, use the 74AHC573BQ,115 (CMOS-input version), which supports 2.0 V to 5.5 V and maintains identical pinout and functionality except for input threshold levels.

Is the exposed thermal pad on the DHVQFN20 package required to be soldered?

Per Nexperia's datasheet (Section 5.1), the exposed pad (terminal 1) has no electrical requirement to be soldered, but if connected, it must remain floating or tied to GND. For optimal thermal performance and mechanical reliability, Aetrix recommends connecting it to a dedicated PCB GND plane with ≥4 thermal vias.

How does the 74AHCT573BQ,115 handle input overvoltage conditions?

Its inputs are overvoltage tolerant up to 5.5 V regardless of VCC level, allowing safe interfacing with 5 V buses even when powered from lower supplies (e.g., 3.3 V). This is achieved via internal clamping structures-not external diodes-and is validated per JEDEC JS-001 HBM ≥2000 V and JS-002 CDM ≥1000 V.