Buck Converter

Vout = Vin × D

Quick answer

This calculator solves Vout = Vin × D for Output Voltage. With Input Voltage 26.4 V, Duty Cycle 50 %, the result is 13.2 V. It solves in 3 directions, so you can enter the values you have and get the one you need.

Calculator

Output Voltage (V)
—

Formula

Vout = Vin × D

Description

A buck converter is a switching regulator that steps voltage down efficiently by rapidly switching the input on and off and filtering the result with an inductor and capacitor. The duty cycle D (the fraction of each switching period during which the input is connected) directly determines the output voltage in continuous conduction mode. Unlike a linear regulator which wastes excess voltage as heat, the buck converter transfers energy magnetically through the inductor, achieving typical efficiencies of 85-95%. The output voltage is always less than or equal to the input voltage.

Variables

  • Vout — Output voltage (V)
  • Vin — Input voltage (V)
  • D — Duty cycle (0 to 1)

Practical Notes

This ideal formula assumes continuous conduction mode and 100% efficiency. Real converters have slightly different transfer functions due to diode drops, MOSFET on-resistance, and inductor DCR. At very light loads, the converter may enter discontinuous conduction mode where the relationship changes. Switching frequencies typically range from 100kHz to several MHz.

Symbols and units

Symbol Meaning Default unit Accepted units
Vout Output Voltage V pV, nV, µV, mV, V, kV
Vin Input Voltage V pV, nV, µV, mV, V, kV
D Duty Cycle — —, %

Step by step

  1. 1. What you know: Input Voltage 26.4 V, Duty Cycle 50 %
  2. 2. The relation: Vout = Vin × D
  3. 3. Substitute: Vin = 26.4 V, D = 50 %
  4. 4. Result: Output Voltage = 13.2 V

Worked examples

Minimum range

Given: Input Voltage 0.726 V, Duty Cycle 2.5 %

Result: Output Voltage = 18.15 mV

Low range

Given: Input Voltage 7.26 V, Duty Cycle 25 %

Result: Output Voltage = 1.815 V

Typical

Given: Input Voltage 26.4 V, Duty Cycle 50 %

Result: Output Voltage = 13.2 V

High range

Given: Input Voltage 0.506 kV, Duty Cycle 0.8

Result: Output Voltage = 0.4048 kV

Maximum range

Given: Input Voltage 5.06 kV, Duty Cycle 8

Result: Output Voltage = 40.48 kV

Solving for each variable

Solve for Output Voltage

Input Voltage 0.726 V, Duty Cycle 2.5 % → 18.15 mV

Solve for Input Voltage

Output Voltage 0.33 V, Duty Cycle 2.5 % → 13.2 V

Solve for Duty Cycle

Output Voltage 0.33 V, Input Voltage 0.726 V → 45.45 %

How Output Voltage changes with Input Voltage

Input Voltage (input) Output Voltage (result)
2.64 V 1.32 V
6.6 V 3.3 V
13.2 V 6.6 V
19.8 V 9.9 V
26.4 V 13.2 V
39.6 V 19.8 V
52.8 V 26.4 V
105.6 V 52.8 V
0.1848 kV 92.4 V
0.264 kV 132 V

The same result in other units

Unit Value
mV 13200
V 13.2
kV 0.0132

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Frequently asked questions

How do you calculate Buck Converter?

Use Vout = Vin × D. With Input Voltage 26.4 V, Duty Cycle 50 %, Output Voltage works out to 13.2 V.

What is the formula for Buck Converter?

The formula is Vout = Vin × D. A buck converter is a switching regulator that steps voltage down efficiently by rapidly switching the input on and off and filtering the result with an inductor and capacitor.

How do you find Input Voltage when you know the other values?

Rearrange for Input Voltage: with Output Voltage 0.33 V, Duty Cycle 2.5 %, Input Voltage is 13.2 V.

How do you find Duty Cycle when you know the other values?

Rearrange for Duty Cycle: with Output Voltage 0.33 V, Input Voltage 0.726 V, Duty Cycle is 45.45 %.

What units does Buck Converter use?

Output Voltage is shown in mV, V, kV. Values are held in SI base units internally, so you can mix prefixes without converting by hand.

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