Boost Converter Calculator

Boost Converter Calculator. A boost converter steps up a lower DC voltage to a higher one — commonly used in power supply design for electronics, LED drivers, and battery-powered devices. Enter your minimum and typical input voltage, output voltage, maximum output current, efficiency, switching frequency, and ripple current factor into the Boost Converter Calculator to get the duty cycle. Secondary outputs include inductor ripple current, maximum switch current, input current, and required inductance. Also try the find Output Voltage with LM317 Voltage Regulator Calculator.

Boost Converter Calculator inputs
V
V
V
A
%
Hz

Typical range: 0.2-0.5

μH
V

Results

Duty Cycle

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Inductor Ripple Current

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Maximum Switch Current

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Input Current

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Required Inductance

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What is a boost converter?

A boost converter is a DC-to-DC power converter that steps up voltage from its input to its output. It's a type of switched-mode power supply that uses energy storage elements (inductors and capacitors) along with switches to efficiently convert lower input voltages to higher output voltages.

How do you calculate the duty cycle for a boost converter?

The duty cycle (D) of a boost converter is calculated using the formula: D = 1 - (Vin / Vout). This represents the fraction of time the switch is ON during each switching cycle. For example, if Vin = 12V and Vout = 24V, then D = 1 - (12/24) = 0.5 or 50%.

How do you choose the boost converter switching frequency?

Switching frequency affects component size, efficiency, and EMI. Higher frequencies allow smaller inductors and capacitors but increase switching losses. Typical frequencies range from 50kHz to 2MHz. Choose based on your size constraints, efficiency requirements, and EMI considerations.

What is the difference between buck and boost converter?

A buck converter steps down voltage (Vout < Vin) while a boost converter steps up voltage (Vout > Vin). Buck converters have duty cycles less than 1 and are used for voltage reduction, while boost converters use the stored energy in inductors during switch-off periods to achieve voltage multiplication.

How do you select the inductor value for a boost converter?

Inductor value affects ripple current and converter size. Use the formula: L = (Vin × D) / (ΔIL × fs), where ΔIL is the desired ripple current and fs is switching frequency. Smaller inductors have higher ripple current but are more compact. Typical ripple current is 20-40% of average inductor current.

What is inductor ripple current and why is it important?

Inductor ripple current is the AC component of current flowing through the boost inductor, representing the difference between peak and minimum current. It affects component stress, efficiency, and output ripple. Lower ripple current reduces component stress but requires larger inductors.

How do you calculate the maximum switch current in a boost converter?

Maximum switch current equals the peak inductor current: Iswitch_max = IL_avg + ΔIL/2, where IL_avg is the average inductor current and ΔIL is the ripple current. This determines the current rating requirements for your switching device (MOSFET or transistor).