Surface-mount anti-fuse prevents chains of LEDs from extinguishing
Murata has developed a surface-mount anti-fuse to prevent long chains of LEDs from extinguishing if one device goes open circuit.
The idea is that anti-fuses are connected across LEDs in the string, one per LED.
When an LED fails, the voltage across its anti-fuse partner increases rapidly.
Once it reaches 20V, a layer of an undisclosed material in the anti-fuse changes permanently from high to low resistance.
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This shorts out the offending LED and re-established current flow to all of the others.
“High voltage shifts the state of the anti-fuse irreversibly from high resistance to low resistance, from over 1M? to under three Ohms,” sales manager Mike Ball told Electronics Weekly.
On switching time, all Ball would reveal is “Instantly”.
Leakage current before switching is under 100nA, and after switching current rating depends on part number and is up to 500mA.
Voltage drop after switching is nominally 4V, said Ball.
Application in and large outdoor high-maintenance lighting fixtures is expected.
See also: Electronics Weekly’s roundup of content related to LEDs, with a special focus on both white LEDs and coloured LEDs:Tags: develops, LEDs, Murata, surface-mount