Boost Converter Calculator
Calculate duty cycle, inductance, and other parameters for DC-DC boost converter circuits
Power Electronics Calculator
Design Mode
Calculate duty cycle and inductance from voltage requirements
Input: Vin, Vout → Output: D, L
Analysis Mode
Calculate output voltage from given duty cycle
Input: Vin, D → Output: Vout
DC input voltage to be boosted
Desired output voltage (must be > Vin)
Rate of the power switch operation
Peak-to-peak inductor current variation
Boost Converter Results
Primary Formula: D = 1 - (Vin / Vout) = 1 - (0V / 0V)
Example Calculations
Example 1: Battery Charger (5V to 12V)
Input: Vin = 5V, Vout = 12V, fs = 100kHz, Iripple = 100mA
Duty Cycle: D = 1 - (5V / 12V) = 0.583 = 58.3%
Inductance: L = (5V × 0.583) / (100kHz × 0.1A) = 291.5μH
Application: USB power bank boost converter
Example 2: LED Driver (3.3V to 24V)
Input: Vin = 3.3V, Vout = 24V, fs = 500kHz, Iripple = 50mA
Duty Cycle: D = 1 - (3.3V / 24V) = 0.863 = 86.3%
Inductance: L = (3.3V × 0.863) / (500kHz × 0.05A) = 113.9μH
Note: High duty cycle reduces efficiency significantly
Example 3: Solar Panel MPPT (18V to 36V)
Input: Vin = 18V, Vout = 36V, fs = 50kHz, Iripple = 200mA
Duty Cycle: D = 1 - (18V / 36V) = 0.5 = 50%
Inductance: L = (18V × 0.5) / (50kHz × 0.2A) = 900μH
Efficiency: ~95% due to optimal duty cycle
Duty Cycle Guidelines
Frequency Selection
Applications
Understanding Boost Converters and Power Electronics
How Boost Converters Work
A boost converter is a DC-to-DC power converter that steps up voltage from its input to its output. It uses energy storage in an inductor and controlled switching to achieve voltage gain greater than 1.
Key Components
- •Inductor (L): Stores energy when switch is ON, releases when OFF
- •Switch (Q): Controls energy flow timing (MOSFET/BJT)
- •Diode (D): Prevents reverse current flow
- •Capacitors: Filter input/output and reduce ripple
Design Considerations
Duty Cycle Trade-offs
- • Low D: High efficiency, low boost ratio
- • High D: High boost ratio, lower efficiency
- • Optimal range: 30-70% for most applications
- • Avoid D > 80% due to poor regulation
Frequency Selection
- • Higher fs: Smaller components, more losses
- • Lower fs: Larger components, better efficiency
- • Consider EMI and thermal constraints
- • Balance size vs. performance requirements
Circuit Operation Modes
Switch ON Period (Ton)
Current flows through inductor and switch. Inductor stores energy from input source. Diode is reverse-biased, output capacitor supplies load current.
Switch OFF Period (Toff)
Inductor releases stored energy through diode to output. Current decreases linearly. Output voltage equals input plus inductor voltage drop.