Nexperia USA Inc. 74HCT574D,652

Overview

74HCT574D,652 from Nexperia is an octal positive-edge-triggered D-type flip-flop with 3-state non-inverting outputs, designed for bus-oriented digital systems requiring data latching and controlled output isolation. It operates at 4.5 V to 5.5 V, features TTL-compatible inputs, supports -40 °C to +125 °C ambient range, and delivers 18 ns typical propagation delay (VCC = 4.5 V, CL = 50 pF), enabling reliable use in industrial control I/O expansion and microcontroller peripheral interfacing.

For engineers reviewing the 74HCT574D,652 datasheet, 74HCT574D,652 pinout, 74HCT574D,652 application, or 74HCT574D,652 equivalent, this device serves as a critical 8-bit transparent latch with precise edge-triggered capture timing, active-low 3-state enable, and robust ESD protection - key considerations for bus arbitration, address/data demultiplexing, and synchronous logic design in embedded systems.

Technical Context

This device implements eight independent D-type flip-flops sharing a common clock (CP) and a single active-low output enable (OE). Each flip-flop captures the logic state of its D-input on the LOW-to-HIGH transition of CP, provided setup (12 ns min @ 4.5 V) and hold (5 ns min) timing requirements are met. The OE input controls all eight outputs simultaneously, placing them in high-impedance state without affecting internal register states.

Input levels conform to TTL thresholds (VIH = 2.0 V min, VIL = 0.8 V max at VCC = 4.5–5.5 V), ensuring direct compatibility with legacy 5 V logic families. Outputs drive ±6 mA loads while maintaining VOH ≥ 3.98 V and VOL ≤ 0.26 V under specified conditions, supporting robust signal integrity in shared-bus environments.

Key Specifications

Pinout & Package

74HCT574D,652 is housed in a plastic small outline package (SO20, SOT163-1) with 20 leads and 7.5 mm body width. Pin 1 is marked by a notch or dot; the package is lead-free and RoHS compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal D-type flip-flop applications.

Compared with SN74HCT574N and 74HCT574PW,118, the 74HCT574D,652 offers optimal balance of industrial temperature rating, SOIC manufacturability, and proven reliability in high-volume industrial control designs - making it the preferred choice for long-lifecycle, surface-mount production.

Availability

74HCT574D,652 is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, microcontroller peripheral interface, automated test equipment signal conditioning, and digital audio control bus buffering requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for 74HCT574D,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 global semiconductor expert focused on essential efficiency technologies, delivering high-performance logic, analog, and MOSFET solutions for automotive, industrial, and consumer markets.

The 74HCT574 series belongs to Nexperia's industry-standard logic portfolio, engineered specifically for robust, pin-compatible replacement of legacy 74-series functions in modern 5 V digital systems with enhanced ESD tolerance and extended temperature operation.

FAQ

Can 74HCT574D,652 operate at 3.3 V?

No. The 74HCT574 variant is specified only for 4.5 V to 5.5 V supply. At 3.3 V, input thresholds fall outside TTL-compatibility range and output drive degrades significantly. For 3.3 V systems, use 74LVC574 or 74AHC574 instead - both support 3.3 V operation with appropriate input voltage compatibility and output swing.

What happens to the outputs when OE is HIGH and CP toggles?

When OE is HIGH, all Q outputs enter high-impedance (OFF) state regardless of CP activity. Internal flip-flop states remain unchanged and retain their last latched values. Only the output drivers are disabled - no data is lost, and the register continues to hold its contents until OE returns LOW.

Is there a version with inverted outputs?

No. The 74HCT574 family provides only non-inverting 3-state outputs. For inverted functionality, use the complementary 74HCT573 octal transparent latch (non-clocked, OE-controlled) or combine 74HCT574 with external inverters. No pin-compatible inverting flip-flop variant exists in the HCT series.

How does the 74HCT574D,652 handle input overvoltage?

Inputs include clamp diodes to VCC and GND, allowing safe interface to signals up to VCC + 0.5 V or down to -0.5 V when current-limited with external resistors. This protects against transient overshoot in mixed-voltage systems but does not support sustained overvoltage beyond absolute maximum ratings (±20 mA clamping current).