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  2. List of LED failure modes - Wikipedia

    en.wikipedia.org/wiki/List_of_LED_failure_modes

    Reverse bias: Although the LED is based on a diode junction and is nominally a rectifier, the reverse-breakdown mode for some types can occur at very low voltages and essentially any excess reverse bias can cause immediate degradation, and may lead to vastly accelerated failure. 5 V is a typical maximum reverse bias voltage specification for ...

  3. Light-emitting diode physics - Wikipedia

    en.wikipedia.org/wiki/Light-emitting_diode_physics

    A LED is a long-lived light source, but certain mechanisms can cause slow loss of efficiency of the device or sudden failure. The wavelength of the light emitted is a function of the band gap of the semiconductor material used; materials such as gallium arsenide , and others , with various trace doping elements , are used to produce different ...

  4. LED circuit - Wikipedia

    en.wikipedia.org/wiki/LED_circuit

    This causes the LED to turn on and off at the frequency of the AC supply. Most LEDs have relatively low reverse breakdown voltage ratings compared to standard diodes, so it may be easier than expected to enter this mode and cause damage to the LED due to overcurrent. However, the cut-in voltage is always less than the breakdown voltage, so no ...

  5. LED lamp - Wikipedia

    en.wikipedia.org/wiki/LED_lamp

    A 230-volt LED filament lamp, with an E27 base. The filaments are visible as the eight yellow vertical lines. An assortment of LED lamps commercially available in 2010: floodlight fixtures (left), reading light (center), household lamps (center right and bottom), and low-power accent light (right) applications An 80W Chips on board (COB) LED module from an industrial light luminaire, thermally ...

  6. Light-emitting diode - Wikipedia

    en.wikipedia.org/wiki/Light-emitting_diode

    Though dual-LED packages exist that contain a different color LED in each direction, it is not expected that any single LED element can emit visible light when reverse-biased. [citation needed] It is not known if any zener diode could exist that emits light only in reverse-bias mode. Uniquely, this type of LED would conduct when connected ...

  7. IEC 61000-4-2 - Wikipedia

    en.wikipedia.org/wiki/IEC_61000-4-2

    IEC 61000-4-2 is the International Electrotechnical Commission's immunity standard on electrostatic discharge (ESD). The publication is one of the basic EMC standards of the IEC 61000–4 series. The European equivalent of the standard is called EN 61000-4-2. The current version of the IEC standard is the second edition dated 2008-12-09. [1]

  8. Freed Israeli hostages did not know their loved ones had died

    www.aol.com/freed-israeli-hostages-did-not...

    For the Israeli hostages freed Saturday, the suffering did not end when Hamas militants paraded their frail and gaunt figures on a stage in Gaza ahead of their release to the Red Cross.

  9. Avalanche diode - Wikipedia

    en.wikipedia.org/wiki/Avalanche_diode

    [dubious – discuss] This feature provides better surge protection than a simple Zener diode and acts more like a gas-discharge tube replacement. Avalanche diodes have a small positive temperature coefficient of voltage, whereas diodes relying on the Zener effect have a negative temperature coefficient. [2] [dubious – discuss]