DC-DC Converters
Every dc-dc converters calculator on CalcEngines — unit converters, derived indices and interpretive tools, each with its formula, a worked example and the reference intervals it is judged against.
11 calculators in this section
- Boost Converter DesignerDesign the power stage of a step-up (boost) converter: duty cycle, inductance, input and peak currents, RMS currents, output capacitance and ESR for a ripple target, the right-half-plane zero and the nearest standard parts.
- Buck Converter DesignerDesign the power stage of a step-down (buck) converter: duty cycle, inductance, peak and RMS currents, minimum output capacitance and ESR for a ripple target, the CCM/DCM boundary, and the nearest standard inductor and capacitor.
- Buck-Boost Converter DesignerDesign an inverting buck-boost converter, which makes a negative output from a positive input: duty cycle, inductance, peak and RMS currents, switch voltage stress, output capacitance and ESR, the right-half-plane zero and standard parts.
- Charge Pump CalculatorSwitched-capacitor voltage doubler, inverter and n-stage Dickson multiplier: the output voltage under load, the ripple, the efficiency, and the number that actually decides the design — the equivalent output resistance, 1/(f·C) per flying capacitor in the slow-switching limit, with the resistance-limited floor named as the other regime.
- DC-DC Efficiency Curve CalculatorAssemble a buck converter's whole loss budget against load — MOSFET conduction and switching, gate drive, the rectifier, inductor DCR and core loss, capacitor ESR and the controller's own quiescent current — and plot efficiency against load current. The shape is the teaching: fixed losses collapse light-load efficiency, I²R takes it away again at full load, and the peak is exactly where the two are equal.
- Flyback Converter CalculatorFirst-pass flyback design from the input range, output and switching frequency: turns ratio, reflected voltage, primary (magnetising) inductance, peak and RMS primary current, MOSFET drain voltage stress and output diode reverse voltage.
- Forward Converter CalculatorDesign a single-switch forward converter with a reset winding: turns ratio, duty cycle across the input range, output inductor and capacitor, magnetising current, the reset duty limit, MOSFET voltage stress and the ratings of all three diodes.
- Push-Pull Converter CalculatorCentre-tapped push-pull power stage: turns ratio, the duty cycle per switch and the dead time between them, the output inductor and capacitor, the 2 × Vin the off switch stands at, the peak flux in the core — and how fast a volt-second mismatch walks that flux into saturation, which is the reason this topology is normally run under current-mode control.
- SEPIC Converter DesignerDesign a SEPIC: the one switching topology that steps up or down from the same circuit and keeps the output the right way up. Duty cycle, both inductors for separate or coupled windings, the coupling capacitor and the RMS current that decides its part number, the output capacitor, and every switch and diode stress.
- Soft-Start Capacitor CalculatorThe capacitor on a regulator's soft-start pin, the ramp time it gives and — the part most pages leave out — the inrush the ramp still permits: C_out × dV/dt plus the load current, checked against the converter's current limit, which is the whole reason the pin is there.
- Ćuk Converter DesignerDesign an inverting Ćuk converter: duty cycle, both inductors, the coupling capacitor's voltage, ripple and RMS current, the output capacitor, switch and diode stresses, and the load below which it leaves continuous conduction.