Texas Instruments CY74FCT374ATQCT

Overview

CY74FCT374ATQCT from Texas Instruments is an 8-bit edge-triggered D-type flip-flop register with 3-state outputs, designed for bus-oriented digital systems. It features a buffered clock (CP), common output-enable (OE), ±32 mA output drive, 6.5 ns max propagation delay, and Ioff support for partial-power-down operation. It operates across –40°C to +85°C and is used in data latching, bus buffering, and synchronous interface logic.

For engineers reviewing the CY74FCT374ATQCT datasheet, CY74FCT374ATQCT pinout, CY74FCT374ATQCT application, or CY74FCT374ATQCT equivalent, key selection criteria include 3-state bus compatibility, TTL-level input/output interoperability, Ioff-enabled power sequencing, matched rise/fall times, and QSOP-20 packaging for high-density PCB layouts.

Technical Context

The CY74FCT374ATQCT implements eight independent D-type flip-flops sharing a single positive-edge-triggered clock (CP) and a common active-low output-enable (OE). Its 3-state outputs allow bidirectional bus control without external gating logic. The device uses FCT-family silicon with edge-rate control circuitry to suppress switching noise.

It supports full TTL-compatible voltage thresholds (VIH = 2 V min, VIL = 0.8 V max) and delivers rail-to-rail output swing under load (VOH = 2.4 V min at –32 mA, VOL = 0.55 V max at 64 mA). Ioff functionality disables outputs when VCC = 0 V, preventing backflow current during hot-swap or power-down sequences.

Key Specifications

Pinout & Package

CY74FCT374ATQCT is housed in a 20-pin QSOP (DBQ) package with gull-wing leads, optimized for surface-mount assembly and thermal performance (θJA = 68°C/W). Pin 1 is located in Quadrant Q1 per tape-and-reel orientation standards.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74FCT374ATSOCT, CY74FCT374ATQCT offers superior PCB density and thermal efficiency in compact systems; versus 74AC374SCX, it provides essential Ioff protection and edge-rate control for industrial bus integrity - neither is pin-compatible without layout revision.

Availability

CY74FCT374ATQCT is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, and test instrumentation requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CY74FCT374ATQCT 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, longevity, and industrial-grade qualification.

CY74FCT374ATQCT belongs to TI's FCT logic family, engineered for high-speed, low-noise bus interface applications in harsh environments where signal integrity, power sequencing, and long-term supply stability are critical.

FAQ

What is the maximum clock frequency supported by CY74FCT374ATQCT?

CY74FCT374ATQCT supports typical switching rates up to 250 MHz, with guaranteed timing margins enabling reliable operation at ≥190 MHz in systems meeting its 5 ns minimum clock pulse width and 2 ns setup/hold requirements. The 5.2 ns max propagation delay (tPLH/tPHL) and 5 ns max enable/disable times ensure clean data capture and bus release at high frequencies. Actual maximum frequency depends on load capacitance, supply stability, and PCB routing.

Does CY74FCT374ATQCT support partial power-down, and how does it work?

Yes, CY74FCT374ATQCT supports partial power-down via its Ioff feature. When VCC = 0 V, the Ioff circuitry disables all outputs, limiting leakage current to ±1 µA even if input or output pins are driven to 4.5 V. This prevents damaging reverse current flow during hot-swap events or multi-rail power sequencing - a key requirement in modular industrial controllers where subsystems power up/down independently. The internal flip-flop states remain preserved.

What are the absolute maximum ratings for CY74FCT374ATQCT?

CY74FCT374ATQCT has an absolute maximum supply voltage of –0.5 V to 7 V, DC input/output voltage range of –0.5 V to 7 V, and maximum output sink current of 120 mA per pin. Exceeding these limits risks permanent damage. Recommended operating conditions specify VCC = 4.75–5.25 V, TA = –40°C to +85°C, and IOH/IOL limited to –32/+64 mA. Thermal impedance is 68°C/W (QSOP), requiring appropriate copper pour and airflow for sustained high-current operation.

Can CY74FCT374ATQCT directly interface with TTL devices?

Yes, CY74FCT374ATQCT is fully compatible with TTL input and output logic levels. Its VIH(min) = 2.0 V and VIL(max) = 0.8 V match standard TTL thresholds, while VOH(min) = 2.4 V at –32 mA and VOL(max) = 0.55 V at +64 mA exceed TTL output drive requirements. This allows direct connection to 74LS, 74ALS, and other TTL families without level shifters or pull-up resistors - verified across the full industrial temperature range.

What is the pin 1 marking and orientation for CY74FCT374ATQCT in tape-and-reel packaging?

CY74FCT374ATQCT uses standard QSOP (DBQ) packaging with pin 1 located in Quadrant Q1 of the tape carrier - meaning the sprocket hole nearest pin 1 is in the upper-left corner when the component cavity faces upward and the tape feeds left-to-right. The top-side marking is "FCT374A", laser-etched on the package body. Reel dimensions are 330 mm diameter, 16.4 mm width, with 2500 units per reel.