LED series resistor
Current-limiting resistance and dissipation for an LED string.
Inputs
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Results
- Calculated resistance
- 300 Ω
- Resistor dissipation
- 0.12 W
Displayed power is calculated dissipation, not the recommended component rating. Allow for thermal margin and voltage tolerance.
Formula & guidance
R=(Vs−nVf)/I; PR=I²R
Displayed power is calculated dissipation, not the recommended component rating. Allow for thermal margin and voltage tolerance.
Change the example inputs and check each field’s units. Use equipment datasheets and applicable project standards for final decisions. Results do not establish Canadian electrical-code compliance or certify a design.