Texas Instruments SN74HC574ANS

Overview

SN74HC574ANS from Texas Instruments is an octal edge-triggered D-type flip-flop with 3-state noninverting outputs, designed for bus driving in digital systems. It operates across 2 V to 6 V supply, features low-to-high clock triggering, buffered output-enable (OE), and drives up to 15 LSTTL loads directly. Used in I/O ports and buffer registers within industrial control and data acquisition systems.

For engineers reviewing the SN74HC574ANS datasheet, SN74HC574ANS pinout, SN74HC574ANS application, or SN74HC574ANS equivalent, key selection criteria include its 8-bit latch functionality, 3-state bus interface capability, –40°C to 85°C temperature range, and compatibility with HC logic families in high-density PCB layouts.

Technical Context

This device implements eight independent D-type latches synchronized to the rising edge of CLK, with each flip-flop retaining state until the next clock transition. The OE input controls output impedance independently of internal storage - enabling concurrent data retention and bus isolation.

Its bus-structured pinout (D inputs on one side, Q outputs on the other) supports compact PCB routing in memory-mapped I/O and address/data latching applications. All inputs are CMOS-compatible with VIH/VIL thresholds defined at 2 V, 4.5 V, and 6 V supply levels.

Key Specifications

Pinout & Package

SN74HC574ANS uses a 20-pin plastic DIP (N package) with 300-mil width. Pin spacing is 0.1 inch, compatible with standard through-hole prototyping and industrial PCB footprints.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HCT574N and 74LCX574M, the SN74HC574ANS offers broader supply flexibility (2–6 V) and proven robustness in industrial temperature ranges, making it ideal for retrofitting legacy 5 V systems while maintaining compatibility with newer 3.3 V logic where voltage margins allow.

Availability

SN74HC574ANS is available at Aetrix Electronics and suitable for industrial automation, legacy system repair, and educational electronics projects requiring stable component supply and long-term obsolescence management.

Supply support for SN74HC574ANS 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

Texas Instruments is a U.S.-based semiconductor company founded in 1930, specializing in analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.

The SN74HC574ANS belongs to TI's classic HC logic family, engineered for pin-compatible replacement of TTL devices while delivering CMOS power efficiency and noise immunity in wired-OR and shared-bus architectures.

FAQ

What is the maximum clock frequency supported by SN74HC574ANS?

The SN74HC574ANS supports a maximum clock frequency of 24 MHz at VCC = 4.5 V and TA = 25°C with CL = 50 pF. At VCC = 6 V, fmax rises to 28 MHz under the same conditions. These values assume proper signal integrity, decoupling, and adherence to setup/hold timing requirements - actual system-level frequency may be limited by board layout and load capacitance.

Does SN74HC574ANS support 3.3 V operation?

Yes, SN74HC574ANS fully supports 3.3 V operation. Its specified supply range is 2 V to 6 V, and all electrical characteristics - including VIH (min 2.0 V at VCC = 3.3 V), VOL (max 0.33 V), and output drive - are guaranteed across this range. It is commonly used as a level-tolerant interface between 3.3 V microcontrollers and 5 V peripheral buses.

What is the function of the OE pin on SN74HC574ANS?

The OE (output enable) pin on SN74HC574ANS is an active-low control that places all eight Q outputs in high-impedance state when asserted high. It does not affect internal latch operation - data remains stored and can be updated on subsequent CLK edges even while outputs are disabled. This enables safe bus sharing and dynamic arbitration in multi-master systems.

Can SN74HC574ANS replace SN74LS574 in existing designs?

SN74HC574ANS can replace SN74LS574 in most cases due to identical pinout, function, and 3-state behavior, but requires attention to supply voltage and input thresholds. While LS devices operate at 5 V only and draw higher quiescent current, SN74HC574ANS draws <80 µA at 6 V and accepts 2–6 V supplies. Input thresholds differ: LS uses TTL levels, HC uses CMOS thresholds - verify driver compatibility before substitution.

What package type does SN74HC574ANS use?

SN74HC574ANS uses a 20-pin plastic dual in-line package (PDIP) with 300-mil width and 0.1-inch pin pitch (N package). It is through-hole mountable, RoHS-compliant, and compatible with standard DIP sockets and wave-soldering processes used in industrial PCB assembly.