New 1kW surface-mount single-channel TVS diodes for aircraft applications

A new patented series of Powermite1 MUPT transient voltage suppression (TVS) diode products has been introduced by Microsemi.

The newcomers cater to market trends toward increased aircraft electrification, greater reliability and higher fuel efficiency, all of which are on the rise. This is consequently driving the need for increasingly capable, lighter and smaller TVS solutions that provide superior protection against transient over-voltage occurrences.

Microsemi's new TVS diodes are highly compact, 1,000W surface-mount single-channel devices featuring superior thermal and power handling capabilities, and provide higher reliability functions in avionics applications such as engine control units and actuator controls, power distribution, environmental control, communications and instrumentation systems. Additional applications include circuit protection for ruggedized handheld radios, GPS, communications test equipment, industrial logging equipment, power supplies, and marine and aircraft electrical systems.

"With increased aircraft electrification continuing to increase, our new devices are ideal to capitalize on this market growth. From a global demand perspective, we estimate the overall market for protection devices is likely to reach $1 billion by 2018," said Christophe Warin, senior director of strategic marketing, Microsemi's Power Discrete and Modules Group. "As a leader in high-reliability solutions, Microsemi continues to execute on a full range of innovative product developments to support the stringent and evolving needs of this industry."

The company's TVS diodes provide aircraft and other electrical systems with critical protection by going into avalanche breakdown within no more than a few nanoseconds after a strike, clamping the transient voltage and routing its current to the ground. The new Powermite1 MUPT series also features oxide-passivated chips with high-temperature solder bonds for high surge capability and negligible electrical degradation under repeated surge conditions. Both unidirectional and bidirectional configurations are available.

Measuring less than 1mm high and 2mm square, the new devices' Powermite packaging provides a dramatic one-third reduction in size compared with two-leaded devices in conventional surface mount assembly (SMA) packages. Compared with similarly-sized SOT-23 devices, Powermite delivers superior thermal and power handling capability. In addition to its size advantages, the Powermite package includes a fully metallic bottom (anode) side that eliminates the possibility of solder flux entrapment at assembly, while a unique locking tab design serves as an integral heat sink. Its innovative design makes this device fully compatible for use with automatic insertion equipment.

The Powermite1 MUPT series is 100 percent surge tested and can be supplied in various 'screened' versions (M, MA, MXL and MX) that have been exposed to levels of additional screening tests (similar to those applied to JANTX military-grade devices) to improve reliability. The devices are offered in voltages ranging from 5V to 48V and comply with Moisture classification Level 1 with no dry pack required per IPC/JEDEC J-STD-020B. Devices are rated to withstand a 10/1,000 microsecond pulse, and the peak pulse power rating is 150W at 10/1,000 microseconds. The 1,000W rating is for an 8/20us microsecond pulse.