Texas Instruments CY74FCT2574ATQCT

Overview

CY74FCT2574ATQCT from Texas Instruments is an 8-bit edge-triggered D-type flip-flop register with 3-state outputs, designed for high-speed bus interface applications. It features 25-Ω output series resistors, Ioff partial-power-down support, matched rise/fall times, and TTL-compatible input/output logic levels. Its 6.5 ns maximum propagation delay (tPLH/tPHL) and –40°C to 85°C operating range make it suitable for industrial control backplanes and synchronous data acquisition systems.

For engineers reviewing the CY74FCT2574ATQCT datasheet, CY74FCT2574ATQCT pinout, CY74FCT2574ATQCT application, or CY74FCT2574ATQCT equivalent, key selection criteria include its 25-Ω integrated output termination, 12 mA sink / 15 mA source drive capability, Ioff-enabled power-down isolation, and strict 1.5 ns minimum hold time at 5 V supply - all critical for noise-sensitive, multi-drop digital bus designs.

Technical Context

This device implements eight independent D-type latches synchronized to the low-to-high transition of a common buffered clock (CP), with asynchronous 3-state control via OE. Each flip-flop stores its D-input state only when setup (1.5 ns min) and hold (1.5 ns min) timing requirements are met relative to CP↑.

The integrated 25-Ω series output resistors damp transmission-line reflections without external components, while edge-rate control circuitry ensures matched tPLH/tPHL (2–6.5 ns) and low ground bounce. Ioff functionality disables outputs and blocks reverse current flow when VCC = 0 V, enabling safe hot-insertion in partial-power-down systems.

Key Specifications

Pinout & Package

Package: 20-pin SSOP (DBQ), 0.65 mm pitch, 7.4–7.6 mm width, 12.6–13.0 mm length, 2.65 mm max height.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit registered bus interface applications.

Compared with CY74FCT2574CTQCT, the CY74FCT2574ATQCT trades 1.3 ns of speed for broader voltage margin and lower dynamic current; versus SN74FCT574N, it adds Ioff safety, on-die termination, and surface-mount packaging essential for modern high-density layouts.

Availability

CY74FCT2574ATQCT is available at Aetrix Electronics and suitable for industrial automation backplanes, synchronous data acquisition subsystems, and legacy bus expansion requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CY74FCT2574ATQCT 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 global semiconductor leader delivering analog, embedded processing, and logic solutions with emphasis on reliability, precision, and industrial-grade qualification.

The CY74FCT2574ATQCT belongs to TI's FCT logic family, engineered specifically for noise-immune, high-speed 5 V digital interfacing in industrial control, test equipment, and communications infrastructure.

FAQ

What is the maximum clock frequency supported by CY74FCT2574ATQCT?

CY74FCT2574ATQCT supports a typical switching rate of 250 MHz, with guaranteed timing up to 150+ MHz based on its 6.5 ns maximum propagation delay and 1.5 ns minimum hold time. Actual maximum frequency depends on load capacitance, trace impedance, and supply stability - for 50-pF loads and proper decoupling, sustained 160 MHz operation is achievable per timing analysis in the datasheet.

Does CY74FCT2574ATQCT require external series termination resistors?

No, CY74FCT2574ATQCT integrates 25-Ω output series resistors on all eight outputs, eliminating the need for discrete termination components. This feature reduces PCB component count, saves board space, and ensures consistent impedance matching across all channels - critical for minimizing reflections in multi-drop bus topologies.

How does Ioff functionality protect the system during partial power-down?

CY74FCT2574ATQCT's Ioff circuitry actively disables all outputs and blocks current flow when VCC = 0 V, limiting reverse current to ±1 µA even with up to 4.5 V applied at outputs. This prevents damage to unpowered sections and avoids bus contention during hot-swap events or staged power sequencing in modular industrial systems.

Is CY74FCT2574ATQCT pin-compatible with CY74FCT574T?

Yes, CY74FCT2574ATQCT is functionally and pinout-compatible with CY74FCT574T and other FCT-family octal D-type registers. The datasheet explicitly states "Function and Pinout Compatible With FCT and F Logic", confirming identical pin assignments, electrical behavior, and mechanical footprint - enabling direct replacement in existing designs to improve noise performance.

What are the recommended decoupling practices for CY74FCT2574ATQCT?

TI recommends placing a 0.1 µF ceramic capacitor between VCC (pin 10) and GND (pin 9) within 1 cm of the CY74FCT2574ATQCT package, plus a bulk 4.7 µF tantalum or aluminum electrolytic capacitor nearby. This dual-capacitor strategy suppresses both high-frequency switching noise (via low-ESR ceramic) and low-frequency supply droop (via bulk capacitance), ensuring stable 5 V operation under full 12 mA sink load conditions.