Step 1
Use the maximum allowable inrush current and Ohm’s Law to determine the least allowable resistance at turn on for your application.

Lowest Resistance Calculator

Input Voltage
Max Inrush (A)
Lowest Resistance Needed

Step 2
Determine the maximum steady state current that will flow through the Inrush Current Limiter.

Joules Calculator

Voltage (Vpeak)
Capacitance (µF)
Total Energy (J)

Step 3
Using the formula J = ½CV², determine how much input energy the thermistor will absorb when the device is turned on.

Steady State Current Calculator

Vac/P(out) * 90% efficiency
Output Power
Input Voltage
Steady State