Inverting Buck-Boost Converter Calculator

Written by Great Medico

Updated September 25, 2026 •2 min read

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Electrical results can look precise while a unit, operating mode, or component assumption quietly changes the answer. Inverting Buck-Boost Converter Calculator keeps the calculation tied to the quantities on this page, so you can trace the displayed duty cycle back to the values you entered rather than treating it as a black-box number.

What this calculator does

The Inverting Buck-Boost Converter Calculator turns Input voltage (Vᵢₙ), Output voltage (Vₒᵤₜ) into the page’s Duty cycle using the circuit or component relationship below. Where the page shows supporting quantities, they come from the same idealized model so you can cross-check the headline rather than reading one isolated number.

How to use it

Start with the fields that actually drive this result: Input voltage (Vᵢₙ), Output voltage (Vₒᵤₜ). Keep units consistent with the menus beside the fields and avoid mixing values measured under different conditions. After calculating, change one input at a time if you are comparing scenarios; that makes cause-and-effect much easier to see.

How the calculation works

For the ideal inverting buck-boost relationship, D = |Vout|/(Vin + |Vout|). The page then estimates inductance from L = Vin·D/(f_sw·ΔI), using the switching frequency and permitted ripple current.

Example

Using the page’s default example (Input voltage (Vᵢₙ) = 12 V; Output voltage (Vₒᵤₜ) = 5 V), the calculator reports Duty cycle of 29.411765 %. Change one driving input at a time and confirm the result moves in the direction predicted by the equation; that is a quick way to catch a unit or mode mistake.

How to interpret the result

Interpret the Duty cycle as an idealized circuit/component quantity for the exact mode and units entered. Use it to compare designs or check hand calculations, but keep component tolerances, ratings, frequency dependence, and real operating conditions in view before turning the number into a hardware decision.

Limitations and notes

The duty-cycle relation is ideal. Switching loss, diode/transistor drops, discontinuous conduction, ESR, saturation current, control-loop behavior, and minimum component ratings are not included.