This forward-converter calculator estimates ideal output voltage and output inductance from input voltage, duty cycle, turns ratio, frequency, and ripple current.
Physics
Forward Converter Calculator
Estimate ideal forward-converter output voltage and output inductance.
Calculator
About this calculator
Formula notes
output voltage = input x duty x (secondary turns / primary turns); inductance = input x duty x (1 - duty) / (ripple current x frequency x turns ratio).
Worked examples
- Example: 24 V, 40% duty, 20:10 turns, 100 kHz, and 500 mA ripple give 4.8 V and 57.6 uH.
- With 12 V input, 30% duty, 10:5 turns, 50 kHz, and 1 A ripple, the ideal output is 1.8 V and inductance is 28.8 uH.
How to use it
- Enter input voltage, duty cycle, and winding turns.
- Enter switching frequency and ripple current.
- Read turns ratio, output voltage, and inductance.
Frequently asked questions
Does this include converter losses?
No. It is an ideal continuous-mode estimate without leakage, core, or switching losses.
Why must duty stay below 100%?
A real forward converter needs reset time, so the tool rejects a full 100% duty cycle.
Limits and interpretation
- The estimate assumes ideal continuous conduction without reset winding detail, leakage inductance, core losses, diode drops, or switching losses.
- Use conservative margins and validate the design with transformer data, snubbing, thermal, and EMI checks before hardware.