App note: Eye safety for proximity sensing using infrared light-emitting diodes

A guide to human eye safety for designers of consumer products, app note from Renesas. Link here (PDF) Active Proximity Sensing for Consumer products requires the use of a light-emitting component to illuminate the target object to be detected at some distance from the sensor. Typically, product designers do not want the illumination to interfere […]

App note: Eye safety of IREDs used in lamp applications

This application note from OSRAM describes the possible hazards of infrared LEDs (IREDs) used for lamp applications with respect to the IEC-62471 standard and how to classify IREDs according to different risk groups. Link here (PDF) As the radiated optical power of light emitting diodes (LEDs) has increased in recent years, the issue of eye […]

Metal oxide varistors catch fire in surge protection devices

Arhi tipped us off to a potential problem in cheap surge protection devices. The metal oxide varistors (MOVs) found in surge protectors are prone to catching fire in cases of extended current surges. MOVs are designed to suck up short surges that might occur on power lines. Unfortunately, in case of prolonged surges MOVs break […]