Forward Converter Calculator
Calculate output voltage and ripple current for forward converter circuit design
Calculate Forward Converter Parameters
DC input voltage to the forward converter
Percentage of time the switch is ON (0-99%)
Number of turns in primary winding
Number of turns in secondary winding
Switching frequency of the MOSFET
Output filter inductance (L1)
Example Calculation
9V Power Supply
Input: 15V DC
Duty cycle: 30%
Primary windings: 20 turns
Secondary windings: 40 turns
Switching frequency: 150 kHz
Output inductance: 180 μH
Results
Windings ratio: N = 20/40 = 0.5
Output voltage: Vout = 0.3 × 0.5 × 15V = 2.25V
Ripple current: Iripple = (0.3 × 0.7 × 0.5 × 15) / (180×10⁻⁶ × 150×10³) = 58.3mA
Note: Actual example gives 9V output with different parameters
Converter Types
Forward
Direct energy transfer
Continuous current flow
Flyback
Energy storage transfer
Discontinuous operation
Buck
Step-down only
No isolation
Forward Converter Advantages
Galvanic isolation between input and output
Direct energy transfer during ON period
Continuous current flow
Better for higher power applications
Lower output ripple current
Understanding Forward Converters
What is a Forward Converter?
A forward converter is a DC-DC converter that provides galvanic isolation using a transformer with an ungapped core. Unlike flyback converters, it transfers energy directly from input to output during the switch-ON period, providing continuous current flow and better regulation.
How It Works
When the switch is ON, energy flows directly through the transformer to the output. The reset winding (1:1 ratio with primary) ensures the transformer core is reset during the switch-OFF period, preventing core saturation. The output inductor maintains continuous current flow.
Applications
- •Telecommunications equipment
- •Computer servers and power supplies
- •Battery chargers
- •Automotive electronic control units
Key Design Formulas
Output Voltage
Vout = D × N × Vin
N = Np / Ns
Ripple Current
Iripple = (D × (1-D) × N × Vin) / (L × fs)
Design Guidelines
• Duty cycle: 20% ≤ D ≤ 70%
• Reset winding: Nd = Np (1:1 ratio)
• Higher frequency → smaller components
Note: Forward converters are typically used for medium to high power applications (50W to several kW) where isolation and continuous current flow are required.