TVS diodes protect avionics from lightning transients

August 14, 2013 // By Graham Prophet
Transient voltage suppression diodes protect aircraft electrical systems from damage caused by dangerous lightning strikes, and with ratings of 6.5kW and 7.5kW, are also suited to other demanding aviation, military, automotive and industrial applications

Microsemi has announced two plastic large area device (PLAD) transient voltage suppression (TVS) diode products; the 6.5 kW and 7.5 kW devices are the latest addition to Microsemi’s PLAD TVS product portfolio and feature 50% smaller footprints than the company’s current 15 kW and 30 kW (pictured, right) solutions. The new TVS diodes are offered in voltages ranging from 10V to 48V and comply with industry-standard RTCA DO-160 requirements for lightning protection in aircraft.

Features include Microsemi’s low-profile PLAD surface mount package, which allows product developers to reduce board space and overall component weight. The highly-integrated, single-component diodes are also more reliable than alternative multiple-device solutions, making them ideal for demanding aviation, military, automotive and industrial applications.

Microsemi’s TVS diodes provide aircraft 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 trend towards aircraft electrification, greater reliability and higher fuel efficiency is on the rise, which is driving the need for increasingly robust, lighter and smaller TVS solutions that provide superior protection against transient over-voltage occurrences,” said Durga Peddireddy, director of marketing and applications for Microsemi’s High Reliability Group. The company’s TVS products are currently used in multiple engine control units and actuator controls, as well as a variety of power distribution, environmental control, communications and instrumentation systems.

Microsemi’s PLAD package offers rugged construction with no wire bonds and high surge capabilities. An exposed pad on the bottom of the diode enables excellent thermal resistance. Moisture Classification is Level 1 with no dry pack required per IPC/JEDEC J-STD-020.

All of Microsemi's PLAD packaged devices are 100% 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. Material and manufacturing changes