LEDs driven by AC without transformers or rectifiers.
Ontology highlight
ABSTRACT:
SUBMITTER: Hughes RW
PROVIDER: S-EPMC7807037 | biostudies-literature | 2021 Jan
REPOSITORIES: biostudies-literature
Publications
LEDs driven by AC without transformers or rectifiers.
Hughes Robin W RW Warner Mark M
Scientific reports 20210113 1
We explore the driving of LEDs by untransformed AC. An extreme case is driving 1.9 V threshold (red) LEDs with UK mains, peak voltage 325 V. Commonly, driving is by transformed, rectified (DC) supply with a series resistor (where a significant fraction of the power is wasted) to limit current in the LED. With AC, one can instead reactively limit to a maximum current safe for an LED by employing a series capacitive impedance. Cheaper and simpler supplies can thus be employed in some cases. We ana ...[more]
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