Editing Pro Electron (section)

=== Frequently used first letters in European active devices ===

**'''A''' [[Germanium]] (or any semiconductor with junctions in a material with a band gap of 0.6 to 1.0eV)
**'''B''' [[Silicon]] (or band gap of 1.0 to 1.3eV)
**'''C''' [[Boron group|III]]-[[Nitrogen group|V]] semiconductors with a band gap of 1.3eV or more, like [[gallium arsenide]] in [[Light-emitting diode|LED]]s
**'''D''' may be...
***Semiconductors with a [[band gap]] less than 0.6eV, such as [[indium antimonide]] in [[infrared detector]]s (rarely used), '''or'''
***(Mullard–Philips) 1.4V (or less) filament tubes
**'''E''' (Mullard–Philips) tubes with a 6.3V heater
**'''F''' Digital integrated circuits
**'''P''' (Mullard–Philips) tubes for a 300mA series heater supply
**'''R''' Devices without junctions, e.g. [[cadmium sulfide]] in a [[photoresistor]]
**'''S''' Solitary digital integrated circuits
**'''T''' Linear integrated circuits
**'''U''' may be...
*** (Mullard–Philips) tubes for a 100mA series heater supply, '''or'''
*** Mixed digital/analogue integrated circuits