Enter values
Formula and methodology
R = (supply voltage − total LED forward voltage) / current. Resistor dissipation is I²R; the suggested standard power rating is at least twice the calculated dissipation.
How to use the result
Check that each input uses the intended unit, then compare the displayed result with the assumptions above. Recalculate when the source values or operating conditions change. Do not use an estimate as a substitute for equipment documentation or professional review where safety depends on the result.
Reviewed sources
- TLC59208F LED driver data sheet, detailed design procedure — Texas Instruments; reviewed September 1, 2026.
- NIST Guide to the SI, Appendix B.9 — National Institute of Standards and Technology; reviewed September 1, 2026.
Method reviewed September 1, 2026. Scheduled review by 2028-08-31.