NXP Semiconductors 74HCT573D,652

Overview

74HCT573D,652 from Nexperia is an octal D-type transparent latch with 3-state outputs, designed for bus-oriented digital systems requiring data latching and controlled output isolation. It features TTL-compatible input thresholds (VIH = 2.0 V min, VIL = 0.8 V max at VCC = 5 V), operates from 4.5 V to 5.5 V, supports -40 °C to +125 °C ambient range, and delivers 18 ns typical propagation delay (Dn→Qn) at VCC = 4.5 V, CL = 50 pF - enabling reliable interfacing with 5 V microcontrollers and legacy logic buses.

For engineers reviewing the 74HCT573D,652 datasheet, 74HCT573D,652 pinout, 74HCT573D,652 application, or 74HCT573D,652 equivalent, this device serves as a critical bidirectional bus interface component where precise timing control, latch transparency during LE HIGH, and high-impedance output disable via OE are essential for avoiding bus contention in embedded I/O expansion and memory-mapped peripheral designs.

Technical Context

The 74HCT573D,652 implements eight independent D-type latches with shared LE (latch enable, active HIGH) and OE (output enable, active LOW) controls. Its TTL-level inputs allow direct connection to 5 V bipolar logic families without level translation, while CMOS output stages provide rail-to-rail swing and 3-state capability.

Operation is strictly defined by the function table: when LE = HIGH, Qn follows Dn (transparent mode); when LE transitions LOW, the last valid Dn values are latched; OE = HIGH forces all Qn into high-impedance regardless of latch state - decoupling output behavior from storage state for flexible bus arbitration.

Key Specifications

Pinout & Package

74HCT573D,652 is packaged in SO20 (SOT163-1): plastic small outline, 20-pin, 7.5 mm body width, surface-mountable with gull-wing leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HCT573N and 74HCT573PW,118, the 74HCT573D,652 offers identical functional behavior and timing but in the industry-standard SO20 footprint - balancing mechanical robustness, thermal performance, and compatibility with mainstream SMT reflow processes without requiring redesign for DIP or ultra-thin TSSOP constraints.

Availability

74HCT573D,652 is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, automotive body control modules, legacy microcontroller bus interfaces, and test equipment digital pattern generation requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74HCT573D,652 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 leading semiconductor manufacturer specializing in high-performance logic, analog, and discrete components, with core expertise in energy-efficient, reliable, and scalable solutions for industrial, automotive, and consumer markets.

The 74HCT573 series belongs to Nexperia's broad portfolio of TTL-compatible CMOS logic devices, engineered specifically for seamless integration into 5 V digital systems where interoperability with legacy bipolar logic and low-power operation are both critical design requirements.

FAQ

What is the maximum clock frequency supported by the 74HCT573D,652?

The 74HCT573D,652 is not a clocked sequential device - it has no internal clock input. Its maximum usable data rate depends on propagation delay (18 ns typ D→Q) and system timing margins. For reliable transparent-mode operation, input data must be stable for ≥13 ns before LE HIGH→LOW transition (tsu = 13 ns min) and held ≥9 ns after (th = 9 ns min), supporting effective bus rates up to ~25 MHz in well-designed layouts.

Can the 74HCT573D,652 operate at 3.3 V supply?

No - the 74HCT573D,652 is specified only for 4.5 V to 5.5 V operation. At 3.3 V, its TTL-input thresholds (VIH = 2.0 V min) become unreliable, and output drive strength degrades significantly. For 3.3 V systems, use the pin-compatible 74LVC573A or 74LVCH573A, which are designed for 1.65 V–3.6 V operation with LVCMOS input levels.

How does the latch enable (LE) pin interact with the output enable (OE) pin?

LE and OE operate independently: LE controls data capture (HIGH = transparent, LOW = latched), while OE controls output driver state (LOW = active, HIGH = high-impedance). When OE = HIGH, all Q outputs go to high-Z regardless of LE state or stored data - allowing bus release without altering internal latch contents, enabling safe multi-master arbitration.

Is the 74HCT573D,652 suitable for automotive applications?

The 74HCT573D,652 is qualified for -40 °C to +125 °C operation and meets AEC-Q100 stress test requirements for human body model ESD (2000 V HBM), making it suitable for non-safety-critical automotive applications such as body control modules, infotainment interfaces, and lighting control - provided it is not deployed in ASIL-B or higher safety domains or life-support systems.