Texas Instruments CY74FCT574CTQCT

Overview

CY74FCT574CTQCT from Texas Instruments is a high-speed, low-power 8-bit edge-triggered D-type flip-flop register with 3-state outputs, designed for bus-oriented digital systems. It features a flow-through pinout, 5.2 ns maximum propagation delay, ±32 mA output drive capability, and I_off 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 CY74FCT574CTQCT datasheet, CY74FCT574CTQCT pinout, CY74FCT574CTQCT application, or CY74FCT574CTQCT equivalent, key selection criteria include its 3-state bus interface compatibility, TTL-level input/output logic, 5.2 ns propagation delay at 5 V, I_off protection, and QSOP-20 package suitability for space-constrained PCB layouts.

Technical Context

The CY74FCT574CTQCT implements eight independent D-type flip-flops sharing a common buffered clock (CP) and output-enable (OE) control. Its edge-triggered architecture captures D-input states on the low-to-high CP transition, with setup/hold times of 2 ns and 1.5 ns respectively. The device uses FCT logic family architecture optimized for noise immunity via edge-rate control circuitry and matched rise/fall times.

It supports full TTL-level compatibility-both input thresholds (V_IL = 0.8 V, V_IH = 2.0 V) and output drive (V_OH ≥ 2.4 V at –32 mA, V_OL ≤ 0.55 V at 64 mA). I_off circuitry actively disables outputs when V_CC = 0 V, preventing backflow current during partial power-down-a critical feature for hot-swap and mixed-voltage system designs.

Key Specifications

Pinout & Package

Package: SSOP-20 (DBQ), 0.64 mm pitch, 7.2 mm × 5.3 mm body size, RoHS-compliant NIPDAU lead finish, MSL Level-2-260°C-1 year.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74FCT574CTSOCT and 74AC574SCX, the CY74FCT574CTQCT delivers superior noise immunity via edge-rate control, guaranteed I_off protection for live insertion, and the fastest propagation delay in the FCT family-making it optimal for high-reliability, high-speed 5 V bus applications where layout density and thermal management are constrained.

Availability

CY74FCT574CTQCT is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, microprocessor bus interfacing, test equipment pattern generation, and legacy communication controller designs requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant sourcing.

Supply support for CY74FCT574CTQCT 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 decades of heritage in high-reliability logic families.

The CY74FCT574CTQCT belongs to TI's FCT logic series-designed specifically for high-speed, low-noise, TTL-compatible bus interface applications in industrial, communications, and computing infrastructure.

FAQ

What is the maximum clock frequency supported by CY74FCT574CTQCT?

The CY74FCT574CTQCT has a maximum propagation delay of 5.2 ns and minimum clock pulse width of 5 ns, supporting reliable operation up to approximately 192 MHz in ideal conditions. Actual maximum frequency depends on setup/hold timing margins, load capacitance, and PCB layout; for sustained 100+ MHz operation, ensure proper termination and minimize trace stubs. The CY74FCT574CTQCT datasheet specifies timing under 50 pF load and 5 V supply.

Does CY74FCT574CTQCT support partial power-down mode?

Yes, CY74FCT574CTQCT includes I_off circuitry that actively disables outputs when V_CC = 0 V, limiting back-current to ±1 µA. This enables safe partial-power-down operation in multi-rail systems and hot-swap applications. The internal flip-flop states are retained, and outputs remain in high-impedance regardless of OE or CP state during power loss-confirming CY74FCT574CTQCT compliance with JEDEC JESD78 latch-up immunity requirements.

What is the pinout configuration of CY74FCT574CTQCT and how does it differ from CY74FCT374T?

CY74FCT574CTQCT uses a flow-through pinout: D0–D7 on pins 1–8 (left side), GND on pin 9, V_CC on pin 10, O0–O7 on pins 11–18 (right side), CP on pin 19, and OE on pin 20. This differs from CY74FCT374T, which uses a folded pinout (D and Q interleaved), increasing PCB routing complexity. The flow-through layout of CY74FCT574CTQCT reduces layer count and crosstalk in high-speed bus designs.

Can CY74FCT574CTQCT be used with 3.3 V logic systems?

No, CY74FCT574CTQCT is specified only for 4.75–5.25 V operation and requires TTL-compatible input thresholds (V_IL ≤ 0.8 V, V_IH ≥ 2.0 V). Driving it directly from 3.3 V logic may result in marginal or non-functional high-level recognition. For 3.3 V systems, use TI's 74LVC574A or similar 3.3 V–tolerant registers. The CY74FCT574CTQCT datasheet explicitly defines recommended operating conditions only within the 5 V range.

What are the thermal characteristics of CY74FCT574CTQCT in its QSOP-20 package?

CY74FCT574CTQCT in the SSOP-20 (DBQ) package has a junction-to-ambient thermal resistance (θ_JA) of 68°C/W under standard JEDEC test conditions. At maximum rated output current (64 mA sink per pin, worst-case eight outputs active), power dissipation remains below 150 mW, resulting in <11°C junction rise above ambient at 25°C. Derating is required above 85°C ambient; full specification applies only within –40°C to +85°C operating range.