Skip to main content
CalcPro

Buck Converter Critical Inductance (L_crit), Ripple & CCM Boundary Calculator

Easily calculate and compute buck converter critical inductance (l_crit), ripple & ccm boundary calculator with accurate equations, live formulas, and expert guidance.

Nominal DC input bus voltage.

Regulated DC output voltage.

Minimum expected load current before transitioning to DCM.

PWM switching frequency.

Desired peak-to-peak inductor ripple as % of load current (typically 20-40%).

Calculated Result
19.8 µH

Critical Inductance (L_crit)

Critical Inductance (L_crit)

19.8 µH

Critical Inductance Lcrit U H

19.8

Nominal Duty Cycle D

0.208

Recommended Inductance U H

52.8

Peak To Peak Ripple Current A

0.8

19.8 — µH

Calculation Breakdown

  1. Applied FormulaDetermines the minimum filter inductance required to guarantee continuous conduction mode (CCM) operation down to specified minimum load currents in buck regulators.L_{crit} = \frac{(V_{in} - V_{out}) D}{2 I_{min} f_{sw}}, \quad \Delta I_L = \frac{V_{out}(1-D)}{L f_{sw}}

Buck Critical Inductance Metric Output

Interactive visualization based on your current inputs

Calculated Value
0.05.09.91520Critical Inductance (L_crit)

What Is the Buck Converter Critical Inductance (L_crit), Ripple & CCM Boundary Calculator?

This tool computes buck converter critical inductance (l_crit), ripple & ccm boundary calculator with high precision arithmetic.

How Does the Buck Converter Critical Inductance (L_crit), Ripple & CCM Boundary Calculator Work?

Determines the minimum filter inductance required to guarantee continuous conduction mode (CCM) operation down to specified minimum load currents in buck regulators.

Buck Converter Critical Inductance (L_crit), Ripple & CCM Boundary Calculator Formula & Variables

The core mathematical equation utilized by this calculator is expressed as:

Lcrit=(Vin−Vout)D2Iminfsw,ΔIL=Vout(1−D)LfswL_{crit} = \frac{(V_{in} - V_{out}) D}{2 I_{min} f_{sw}}, \quad \Delta I_L = \frac{V_{out}(1-D)}{L f_{sw}}

Determines the minimum filter inductance required to guarantee continuous conduction mode (CCM) operation down to specified minimum load currents in buck regulators.

How to Use the Buck Converter Critical Inductance (L_crit), Ripple & CCM Boundary Calculator

  1. Enter your parameters into the designated input fields to calculate the result immediately.

Step-by-Step Example Calculation

Buck Converter Critical Inductance (L_crit), Ripple & CCM Boundary Calculator Example

Input Values:

inputVoltageVin:24
outputVoltageVout:5
minimumLoadCurrentIoutMin:0.4
switchingFrequencyKhz:250
targetRippleRatioPercent:30
Worked Steps: Sample evaluation based on standard reference conditions.

Understanding Your Result

The calculated primary figure indicates the optimal or required µH.

Factors That Affect the Result

  • Measurement tolerances, operational variance, and real-world conditions.

When Should You Use This Calculator?

  • Everyday budgeting, technical homework, professional estimation, and household projects.

Assumptions & Limitations

  • Assumes standard atmospheric or environmental parameters unless specified.

Frequently Asked Questions

Calculation Accuracy & Reference Note

Double-precision IEEE 754 arithmetic with validated empirical constants.

\n

Related Calculators

Explore more tools and calculators in Physics Calculators

Length Converter

Convert length and distance between metric and imperial units including meters, feet, inches, kilometers, miles, and yards with exact SI definitions.

Percentage Calculator

Calculate percentages: what % X is of Y, P% of X, % change, discount price, and percentage points.

Temperature Converter

Convert temperatures between Celsius (°C), Fahrenheit (°F), Kelvin (K), and Rankine (°R) with step-by-step thermodynamic formulas.

Ohm's Law & Electrical Power Calculator

Calculate Voltage (V), Current (I), Resistance (R), and Electrical Power (P) across DC circuits.

Density, Mass & Volume Calculator

Calculate density (ρ = m/V), material mass, or physical volume for solids, liquids, and gases.

Steam Turbine Surface Condenser Cooling Water Duty Calculator

Calculates surface condenser thermal heat rejection (MWth), circulating cooling water pumping volume (m³/h), and steam condensation rate.