The SpikeSafe SMU was used to resolve a question regarding UV LED testing that was vexing the IES working group: How to handle the dramatic voltage change that many LEDs exhibit in the first few milliseconds of operation. The voltage change is due to the thyristor effect – a known shortcoming of immature LED products. It was thought that all UV-LEDs might suffer from this problem. A two-temperature transient voltage test was performed using the SpikeSafe SMU. The test showed that some UV-LEDs did not suffer from the thyristor effect. The working group will use this information in the upcoming UV-LED testing standard and the company will use this data to market their LEDs.

Bolb two-temperature transient voltage test shows linear k-factor and only 150mV change in 10ms
Competing UV-LED shows non-linear k-factor and 660mV of change in 10ms – such a large change is not possible due to heating; it must then be the thyristor effect

About Melissa Ford

Melissa Ford is the President and CEO of Vektrex. In this role, Ms. Ford created the Vektrex vision—to innovate and produce advanced, high quality, forward looking solutions that reduce global greenhouse gas emissions for our clients and partners in the semiconductor industry. Ms. Ford has focused the company on this vision, guiding it steadfast in the direction of products, replacing its service only business. Vektrex, under Ms. Ford’s vision and direction, advances the industry globally by defining and setting the standard for high quality LED reliability. Vektrex is the world leader in technology used to measure LED lighting reliability. The company products are made in the USA and distributed worldwide.