STMicroelectronics 74ACT374TTR

Overview

74ACT374TTR from STMicroelectronics is an octal D-type flip-flop with 3-state non-inverting outputs, designed for high-speed data latching and bus interface in TTL- and CMOS-compatible systems. It features 260 MHz typical maximum clock frequency at 5 V, ±24 mA symmetrical output drive, and 4.5–5.5 V operating supply range. Used in address/data bus buffering, memory I/O control, and synchronous logic staging.

For engineers reviewing the 74ACT374TTR datasheet, 74ACT374TTR pinout, 74ACT374TTR application, or 74ACT374TTR equivalent, key selection criteria include 3-state enable timing (tPZL/tPHZ ≤ 11 ns), input compatibility (VIH ≥ 2.0 V, VIL ≤ 0.8 V), propagation delay symmetry (tPLH ≅ tPHL), and TSSOP-20 package suitability for high-density PCB layouts.

Technical Context

The 74ACT374TTR implements edge-triggered storage using a low-to-high clock transition to capture D-input states into eight independent registers. Its 3-state output control operates independently of internal latch operation, enabling data retention during bus contention.

Designed with sub-micron C2MOS technology, it delivers TTL-compatible input thresholds and 50 Ω transmission line driving capability while maintaining 4 µA max quiescent ICC at 25°C. ESD protection provides 2 kV HBM immunity on all pins.

Key Specifications

Pinout & Package

TSSOP-20 package: 6.5 mm × 4.4 mm body, 0.65 mm pitch, 1.1 mm height, lead-free and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar octal D-type flip-flop with 3-state outputs applications.

Compared with SN74ACT374PW and 74VHC374FT, the 74ACT374TTR uniquely combines 260 MHz speed, ±24 mA line drive, and guaranteed 50 Ω transmission line performance - making it optimal for high-speed bus isolation and timing-critical latching where signal integrity is paramount.

Availability

74ACT374TTR is available at Aetrix Electronics and suitable for memory address latching, microprocessor bus interfacing, industrial PLC I/O expansion, and digital test equipment signal staging requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74ACT374TTR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in automotive, industrial, and power management ICs with broad analog, digital, and mixed-signal portfolios.

The 74ACT374TTR belongs to ST's advanced high-speed CMOS logic family, engineered specifically for seamless TTL/NMOS-to-CMOS bridging in industrial control, instrumentation, and legacy system upgrades.

FAQ

What is the minimum pulse width required on the CK input?

The minimum high and low pulse width for CK is 1.5 ns at VCC = 5.0 V, as specified in the AC Electrical Characteristics table. This ensures reliable edge detection and avoids metastability during latch operation. Pulse widths below this threshold may result in incomplete or inconsistent data capture across temperature and voltage extremes.

Can OE be toggled while CK is active without affecting stored data?

Yes - the OE input controls only the output buffer stage and has no effect on internal flip-flop state. Data remains latched and can be updated on subsequent CK edges regardless of OE state, enabling dynamic bus sharing without data loss or corruption.

Is the 74ACT374TTR compatible with 3.3 V logic interfaces?

No - it is strictly a 5 V device with VCC operating range of 4.5–5.5 V and TTL-compatible input thresholds (VIH ≥ 2.0 V). Direct connection to 3.3 V logic requires level-shifting circuitry to avoid undervoltage input recognition and potential damage from VI exceeding VCC + 0.5 V.

What is the significance of the "C2MOS" process mentioned in the datasheet?

C2MOS refers to ST's proprietary complementary silicon gate process with double-layer metal interconnect, enabling high speed, low power, and improved latch-up immunity. It underpins the device's 260 MHz fMAX, 4 µA ICC, and robust ESD tolerance - distinguishing it from older bipolar or single-metal CMOS technologies.