STMicroelectronics 74ACT02TTR

Overview

74ACT02TTR from STMicroelectronics is a quad 2-input NOR gate in TSSOP-14 package, operating at 4.5–5.5 V with 5 ns typical propagation delay, ±24 mA symmetrical output drive, and TTL-compatible input thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V). It interfaces high-speed CMOS systems with TTL/NMOS logic in industrial control and digital signal routing.

For engineers reviewing the 74ACT02TTR datasheet, 74ACT02TTR pinout, 74ACT02TTR application, or 74ACT02TTR equivalent, this device delivers balanced tPLH/tPHL timing, 50 Ω transmission line driving, and 2 kV ESD immunity-key for noise-resilient combinatorial logic in mixed-voltage board designs.

Technical Context

The 74ACT02TTR implements four independent NOR gates using sub-micron C2MOS technology with three-stage buffered outputs, enabling high noise immunity and stable switching. Its symmetrical output impedance (|IOH| = IOL ≥ 24 mA) and balanced propagation delays (tPLH ≅ tPHL) support precise timing-critical combinational logic.

Designed for direct interfacing between advanced CMOS and legacy TTL/NMOS systems, it meets VIH ≥ 2.0 V and VIL ≤ 0.8 V across 4.5–5.5 V supply, while sustaining 50 Ω line driving and transient voltage protection up to ±2 kV HBM ESD.

Key Specifications

Pinout & Package

TSSOP-14 package: 4.9–5.1 mm × 6.25–6.5 mm body, 0.65 mm pitch, 0.5–0.7 mm lead length, 1.1 mm max height. RoHS-compliant, surface-mount, fine-pitch plastic package optimized for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 2-input NOR gate applications.

Compared with SN74ACT02DR and MC74ACT02DT, the 74ACT02TTR offers the smallest footprint and lowest quiescent current, making it optimal for space-constrained, low-power industrial controllers where TSSOP reflow capability exists.

Availability

74ACT02TTR is available at Aetrix Electronics and suitable for industrial PLC I/O expansion, automotive body control modules, digital test equipment signal routing, and communications protocol glue logic requiring stable component supply and long-term manufacturability.

Supply support for 74ACT02TTR 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, designing and manufacturing analog, digital, and mixed-signal ICs for industrial, automotive, and consumer applications.

The 74ACT02TTR belongs to ST's advanced high-speed CMOS logic family, engineered specifically for robust, low-skew, mixed-voltage digital interfacing in harsh industrial and automotive environments.

FAQ

Is the 74ACT02TTR pin-compatible with standard 74-series NOR gates?

Yes, the 74ACT02TTR is fully pin- and function-compatible with the industry-standard 7402 quad 2-input NOR gate. Pin assignments for inputs (A/B), outputs (Y), VCC (pin 14), and GND (pin 7) match exactly, enabling drop-in replacement in existing TSSOP-14 layouts without redesign.

What is the maximum capacitive load the 74ACT02TTR can drive while maintaining 5 ns propagation delay?

The 5 ns typical tPD is specified under AC test conditions with CL = 50 pF and RL = 500 Ω. Driving loads beyond 50 pF increases tPD nonlinearly; for loads >75 pF, propagation delay exceeds 7 ns, and output rise/fall times degrade due to increased RC time constant.

Does the 74ACT02TTR require external pull-up or pull-down resistors on unused inputs?

No. Unused inputs must be tied to VCC or GND to prevent floating states and excessive ICC. The device has no internal pull-ups or pull-downs; leaving inputs unconnected risks oscillation, increased power consumption, and potential damage from noise-induced switching.

Can the 74ACT02TTR operate reliably at 4.5 V supply with full 24 mA output drive?

Yes. At VCC = 4.5 V, the device guarantees IOL/IOH ≥ 24 mA (per gate) with VOL ≤ 0.5 V and VOH ≥ 3.76 V, meeting all DC specifications across the full −55°C to +125°C temperature range, as confirmed in the manufacturer's recommended operating conditions table.