LED-Vorwiderstand-Rechner

Ohmsches Gesetz in drei Schritten

1. Spannung am Widerstand = V_{versorgung − (n × Vf)}
2. Erforderlicher Widerstand = (V_{versorgung − n × Vf) ÷ If}
3. Verlustleistung = If² × R

   Häufige Durchlassspannungen

   Farbe	Typische Vf
   Infrarot	1.5 V
   Rot	2.0 V
   Orange / Gelb	2.1 V
   Grün (hochleuchtend)	3.0 V
   Blau / Weiß	3.2 V
   UV	3.7 V

   Reihe vs. Parallel

   Reihenschaltung (empfohlen): Ein Widerstand für alle LEDs. Gleicher Strom durch jede LED. Spannungen addieren sich.

   Parallelschaltung (vermeiden): Jede LED in Parallelschaltung braucht ihren eigenen Widerstand. Ohne separate Widerstände saugt die LED mit der niedrigsten V_{f den ganzen Strom und brennt zuerst durch.}

   Verwandt

   • English version
   • AC-Dimmer 1-Kanal
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