Texas Instruments CY74FCT574TSOC

Overview

CY74FCT574TSOC 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 common buffered clock (CP), output-enable (OE) control, 64-mA sink / 32-mA source drive strength, and Ioff partial-power-down support. It operates across –40°C to 85°C and is used in data latching and bus isolation applications in industrial control and communications hardware.

For engineers reviewing the CY74FCT574TSOC datasheet, CY74FCT574TSOC pinout, CY74FCT574TSOC application, or CY74FCT574TSOC equivalent, key selection criteria include its 5.2-ns max propagation delay (tPLH/tPHL), 10-ns max enable/disable timing, SOIC-20 package compatibility, and TTL-level input/output interoperability in mixed-logic systems.

Technical Context

The CY74FCT574TSOC implements eight independent D-type flip-flops sharing a single positive-edge-triggered clock (CP) and a common 3-state output-enable (OE) input. Its flow-through pinout simplifies PCB layout versus the 'FCT374T family. Each flip-flop captures D-input state on the low-to-high CP transition, meeting 2-ns setup and 1.5-ns hold time requirements.

Output drivers use FCT logic with edge-rate control circuitry to reduce switching noise, matched rise/fall times, and full TTL-compatible voltage thresholds (VIH = 2 V, VIL = 0.8 V). The Ioff feature disables outputs during power-down to prevent backflow current, supporting hot-insertion and partial-power-down system architectures.

Key Specifications

Pinout & Package

Package: SOIC-20 (DW), 7.5 mm × 12.8 mm body, 1.27 mm pitch, RoHS-compliant NIPDAU lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY74FCT574ATSOCT and SN74FCT574NSR, the CY74FCT574TSOC offers identical core functionality in tube packaging for low-volume or engineering-use cases, with no compromise in timing, drive, or thermal performance - making it ideal for validation, repair, and pilot runs where reel logistics are unnecessary.

Availability

CY74FCT574TSOC is available at Aetrix Electronics and suitable for industrial PLCs, communications backplanes, test equipment, and legacy system upgrades requiring stable component supply and long-term manufacturability.

Supply support for CY74FCT574TSOC 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 specializing in analog, embedded processing, and logic solutions with over 50 years of innovation in high-reliability digital interfaces.

The CY74FCT574TSOC belongs to TI's FCT logic family, engineered for noise-immune, high-drive 5-V bus interfacing in industrial and telecom infrastructure where signal integrity and power-down safety are critical.

FAQ

What is the maximum clock frequency supported by CY74FCT574TSOC?

The CY74FCT574TSOC supports reliable operation up to 100 MHz, derived from its 10-ns maximum propagation delay (tPLH/tPHL) and 2-ns setup/1.5-ns hold timing margins. At 5-V supply and 25°C, typical switching rate reaches 250 MHz, but system-level timing裕度 requires derating for worst-case temperature and voltage conditions. The CY74FCT574TSOC datasheet specifies guaranteed timing only up to 100 MHz for full parametric compliance.

Does CY74FCT574TSOC support hot-swap or partial-power-down operation?

Yes, CY74FCT574TSOC includes Ioff circuitry that disables outputs and limits reverse current to ±1 µA when VCC = 0 V. This allows safe insertion into live backplanes or powered systems without risk of damaging current backflow. The CY74FCT574TSOC maintains this capability across its full operating temperature range and is explicitly qualified for partial-power-down applications per TI's FCT family specifications.

What is the pinout configuration of CY74FCT574TSOC and how does it differ from CY74FCT374T?

The CY74FCT574TSOC uses a flow-through pinout: D0–D7 occupy pins 1–8 (left side), O0–O7 occupy pins 11–18 (right side), with CP on pin 19 and OE on pin 20. This differs from CY74FCT374T, which places outputs adjacent to inputs - causing routing congestion. The CY74FCT574TSOC pinout simplifies PCB layout by enabling straight-through trace routing and reducing layer count in dense bus designs.

Can CY74FCT574TSOC be used as a direct replacement for 74LS374 in existing designs?

Yes, CY74FCT574TSOC is a functional and pin-compatible upgrade for 74LS374 in SOIC-20 packages. It matches TTL input thresholds (VIH = 2 V, VIL = 0.8 V), provides 2× higher output sink current (64 mA vs. 24 mA), and adds Ioff and edge-rate control. No PCB changes are needed, though decoupling capacitor placement should follow FCT guidelines due to faster edge rates. The CY74FCT574TSOC improves noise immunity and power efficiency without altering logic behavior.

What are the thermal characteristics of CY74FCT574TSOC in SOIC-20 package?

The CY74FCT574TSOC in SOIC-20 (DW) package has a junction-to-ambient thermal resistance (θJA) of 58°C/W under standard JEDEC test conditions. Maximum junction temperature is 150°C, and the device is rated for continuous operation from –40°C to +85°C ambient. Power dissipation must remain below 450 mW at 85°C ambient to maintain safe junction temperature, assuming typical ICCD of 1.2 mA/MHz and static ICC of 0.2 mA.