Examples
Examples
Try the starting example
- Supply (V)
- 5
- LED forward voltage (V)
- 2
- Target current (mA)
- 20
- Ideal resistor (Ω)
- 150
- Resistor dissipation (W)
- 0.06
Try another scenario
- Supply (V)
- 5.5
- LED forward voltage (V)
- 2
- Target current (mA)
- 20
- Ideal resistor (Ω)
- 175
- Resistor dissipation (W)
- 0.07
Calculation method
Calculation method
Ideal resistor (Ω)
(a-b) ÷ (c ÷ 1000)
Resistor dissipation (W)
(a-b) × c ÷ 1000
Symbols and units
- a
- Supply (V)
- b
- LED forward voltage (V)
- c
- Target current (mA)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- An ideal resistor calculation; choose real component ratings and tolerances separately. No safety certification is provided.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.
Further reading
Background reading; this does not imply endorsement or independent review of SumFizz.