STMicroelectronics RHFACT14K1

Overview

RHFACT14K1 from STMicroelectronics is a radiation-hardened, high-speed CMOS logic device in the 54ACTxxx series - specifically a quad 2-input NAND gate - designed for aerospace and space-grade digital control systems. It operates at 4.5 V to 5.5 V, delivers TID hardness up to 300 krad(Si), exhibits SEL immunity up to 125 MeV·cm²/mg, and functions across –55 °C to +125 °C in hermetic ceramic Flat-14 packaging.

For engineers reviewing the RHFACT14K1 datasheet, RHFACT14K1 pinout, RHFACT14K1 application, or RHFACT14K1 equivalent, this part supports critical timing, combinatorial logic, and bus interface functions in radiation-intensive environments where latch-up immunity, single-event upset resilience, and guaranteed parametric performance at extreme temperature are mandatory selection criteria.

Technical Context

The RHFACT14K1 implements TTL-compatible input thresholds and CMOS output drive within a QML-V qualified rad-hard process. Its logic structure consists of four independent 2-input NAND gates with buffered outputs, each featuring Schmitt-trigger noise immunity on inputs per AC/ACT family design.

It uses ST's AMK6 6-inch diffusion line silicon, qualified under MIL-STD-883 cond A for total ionizing dose, and characterized against heavy-ion SEE using the 54AC14 test vehicle (Class 1: basic gates & Schmitt triggers), confirming SEL immunity and SEU/SET thresholds at 3 V and 4.5 V operating points.

Key Specifications

Pinout & Package

Ceramic Flat-14 package: 14-terminal surface-mount hermetic package with grounded metallic lid, 1.27 mm pitch, 9.27 mm × 6.19 mm footprint, and 2.72 mm max height. Lid electrically connected to Pin 7 (GND).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 2-input NAND gate applications.

Compared with RHFACT14K1, the 54ACT00 lacks flight certification documentation and lot-level radiation test reports, while RHFAC00 trades SEL immunity for broader voltage operation - making RHFACT14K1 the sole choice for LEO or MEO missions requiring maximum latch-up immunity and QML-V compliance.

Availability

RHFACT14K1 is available at Aetrix Electronics and suitable for onboard command decoder, satellite telemetry formatter, launch vehicle avionics sequencer, and deep-space probe power controller applications requiring stable component supply across extended production lifecycles and radiation-qualified continuity.

Supply support for RHFACT14K1 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, with dedicated rad-hard product lines serving defense, space, and nuclear instrumentation markets since 1985.

RHFACT14K1 belongs to ST's 54ACTxxx rad-hard logic family - engineered specifically for high-reliability digital control in spacecraft, launch systems, and strategic platforms where radiation-induced failures are unacceptable.

FAQ

Is RHFACT14K1 pin-compatible with standard 54ACT00 devices?

Yes - RHFACT14K1 uses the same Flat-14 pinout as generic 54ACT00 SMDs (MIL-PRF-38535), with identical terminal numbering, GND on Pin 7, and VCC on Pin 14. However, it includes additional QML-V screening, lot-level radiation test reports, and grounded-lid construction not present in commercial variants.

What is the maximum operating frequency of RHFACT14K1 at 5 V and 25 °C?

While no absolute maximum frequency is specified in the DB0998 summary, propagation delay is typically <10 ns per gate at VCC = 5 V and 25 °C. Based on SMD 5962F89547, maximum usable frequency in clean PCB layouts with 50 pF loads is ~35 MHz - derated further in high-dose or high-temperature conditions.

Does RHFACT14K1 require external decoupling capacitors?

Yes - a minimum 100 nF X7R ceramic capacitor must be placed within 2 mm of Pin 14 (VCC) and Pin 7 (GND) to suppress switching noise and maintain stable rail voltage during simultaneous output transitions, especially critical in rad-hard systems where transient-induced SEUs must be minimized.

Can RHFACT14K1 be used in circuits with 3.3 V logic interfaces?

No - RHFACT14K1 is an ACT-series device with TTL-compatible inputs requiring VIH ≥ 2.0 V, but its minimum VCC is 4.5 V. For 3.3 V systems, use the AC-series variant RHFAC00 (2–6 V operation) or add level-shifting circuitry; direct 3.3 V interfacing risks undefined logic states and increased susceptibility to noise.