What is Boost converter?

A DC-DC converter that produces a DC voltage higher than its input: the inductor sits on the input side, the switch connects it to ground to store energy, and the energy is then released to the output through a diode. The ideal output voltage in continuous conduction mode is the input voltage ÷ (1 − D), twice the input at D = 0.5. It is used to make 5 V from a lithium-ion battery, to drive LEDs connected in series and in power factor correction (PFC) circuits.

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Japanese name: 昇圧チョッパ(ブーストコンバータ)

Boost converter appears in 6 practice questions across 2 topics, including Power Electronics Circuits, Power semiconductors.

Field: Power Electronics Circuits

Try it: questions about Boost converter

For an ideal step-up chopper (boost converter) with an input voltage of 5 V and a switch duty cycle of 0.6, which of the following is the output voltage in continuous conduction mode?

A3 V
B8 V
C12.5 V

Show answer and explanation

Answer: C. 12.5 V

The output voltage of an ideal boost converter is Vout = Vin/(1 − D). 5 V ÷ (1 − 0.6) = 5 ÷ 0.4 = 12.5 V. The formula follows from the balance of volt-seconds across the inductor, with Vin applied while the switch is on and (Vout − Vin) while it is off: Vin × D = (Vout − Vin) × (1 − D). The 3 V of D × Vin is the formula of the buck converter.

Boost converter in the explanations

The output voltage of an ideal boost converter is Vout = Vin/(1 − D).
For an ideal step-up chopper (boost converter) with an inpu…
A PFC circuit—typically a boost converter—shapes the input current into a sine wave matching the voltage, raising the power factor above 0.95.
What is the purpose of a power factor correction (PFC) circ…
A boost converter stores energy in the inductor while the switch is on, then adds the inductor's voltage to the input when it turns off.
Which DC-DC converter outputs a DC voltage higher than its …
It works as a step-down converter for D < 0.5 and a step-up converter for D > 0.5, and at D = 0.5 the output magnitude equals the input.
For an ideal buck-boost chopper (inverting buck-boost conve…
Formulas such as Vout = D × Vin for the buck converter and Vout = Vin/(1 − D) for the boost converter hold in continuous conduction mode.
Which of the following correctly describes continuous condu…