Properties of LEDs with respect to their functioning are characterized by variations that are due to the manufacturing process. This applies for white and coloured (monochromatic) LEDs. LED manufacturers therefore classify LEDs into "functioning classes (bins)". IEC/PAS 62707-1 specifies general requirements for the binning of LEDs and defines a white binning grid.

This VDE application guide specifies the binning of forward voltage and an optional nomenclature (binning code) for LEDs emitting incoherent, visible radiation.

The selected voltage range from 1,75 V to 4,75 V covers the range of LEDs emitting visible radiation by various semiconductor material applications and thus includes all LEDs for lighting purposes which are on the market.

Different forward voltage ranges are necessary depending on the interconnection of LEDs and the requirements to the uniformity parameters of LEDs. Therefore the subdivision of voltages is useful in the range from 50 mV to 300 mV.

This VDE application guide is based on discussions in IEC/SC 34A which were not continued beyond the stage of committee draft in this international committee. Subcommittee DKE/UK 521.1 "Elektrische Lampen" of the DKE German Commission for Electrical, Electronic & Information Technologies of DIN and VDE (www.dke.de) has adopted this application guide for publication at its meeting in May 2012.