STMicroelectronics Proves Performance Advantage with Silicon Protection Diodes Specified to International Surge Standard IEC 61000-4-5

The STIEC45 Transil™ family provides mandatory protection for power supplies against surges, electrostatic discharge, and electrical fast transients. Metal-Oxide Varistors (MOVs) are usually connected to prevent surge energy reaching the power supply, but silicon surge protectors are more reliable. Among these, only the STIEC45 family is specified according to IEC 61000-4-5.

In addition, ST’s Transils maintain more than 75% of their protection capability up to 150°C, and are soldered to standard-sized metal pads on the pc-board. This approach delivers a space-efficient solution for equipment operating in high-temperature environments, such as factories or vehicles. Alternative silicon devices sometimes require oversized pads to provide the stated surge protection, and the level of protection can decrease rapidly beyond 25°C. At 125°C, some absorb less than 40% of the peak pulse-power specified.

STIEC45-xxAS family highlights include:

• The devices also meet: IEC 61000-4-2 for ESD and IEC 61000-4-4 for Electrical Fast Transient (EFT)

• Pass MIL-STD-883 (Method 3015) ESD tests

• 500A (8/20µs) peak pulse-current capability

• 410A (8/20µs) current capability at 150°C

• Low leakage current: 0.2µA at 25°C; 1µA at 85°C

• Stand-off voltage options: 24V, 26V, 28V, 30V, 33V

Five STIEC45 variants are available, covering stand-off voltages from 24V to 33V. The family is in mass production, in 8 x 6mm SMC surface-mount packages, priced from $0.20 in quantities of 100,000 units.