Gate signal for the Mosfet:
Current through the inductor:
Current through the Mosfet
Current through the Diode
Input current
Output voltage
Voltage over the Mosfet
Voltage over the Diode
| Continuous mode | |||
| Inductor | L | 75 | [μH] |
| Output capacitor | Cout | 220 | [μF] |
| Time the switch is on | Ton | 5.44 | [μs] |
| Time when IL crosses zero | Toff | 10 | [μs] |
| Duty cycle | d | 0.544 | [.] |
| Minimum Inductor current: | Imin | 0.82 | [A] |
| Maximum Inductor current: | Ipeak | 1.18 | [A] |
| Inductor current ripple | iripple | 0.36 | [A] |
| Average input current | iinav | 0.54 | [A] |
| RMS input current | iinrms | 0.74 | [A] |
| RMS inductor current | iLrms | 1.01 | [A] |
| RMS diode current | iDrms | 0.68 | [A] |
| RMS output capacitor current | iCoutrms | 0.1 | [A] |
| RMS input capacitor current | iCinrms | 0 | [A] |
| Output | |||
| Output voltage ripple | vripple | 25 | [mV] |
| Output voltage ripple | vomin | 4987.6 | [mV] |
| Output voltage ripple | vomax | 5012.6 | [mV] |
| Output capacitor ESR | Rc | 70 | [mΩ] |
| Resonant Frequency | FLC | 1.239 | [kHz] |
Control of the buck converter
The selected control method is: Voltage Mode Type III
Voltage Mode - Continuous conduction mode
Control to output
Input to output
Open Loop
K factor method
Error Amplifier
Closed Loop
| Converter | |||
| Zero Capacitor esr | fesr | 10.335 | [kHz] |
| Resonant Frequency | fr | 1.243 | [kHz] |
| Type III Error Amplifier- K factor method | |||
| fugf: | fugf | 5.26 | [kHz] |
| First zero: | fz1 | 2.287 | [kHz] |
| Second zero: | fz2 | 2.287 | [kHz] |
| First pole: | fp1 | 16.883 | [kHz] |
| Second pole: | fp2 | 16.883 | [kHz] |
| Upper feedback resistor: | R1 | 10 | [kΩ] |
| R2 | R2 | 26.605 | [kΩ] |
| R3: | R3 | 1.567 | [kΩ] |
| C1: | C1 | 4.098 | [nF] |
| C2: | C2 | 26.161 | [nF] |
| C3: | C3 | 60.174 | [nF] |
| DC gain | DCGain | 19.83 | [dB] |
| Phase Margin | Pm | 45 | [degrees] |
| Crossover Frequency | fc | 6.213 | [kHz] |
Losses
| Conduction losses | Pcond | 0 | [W] |
Magnetics
| Flux Linkage => Li=NBA | Flux | 8.9E-5 | [x] |
Help
Inputs
The minumum parameters required for designing a SMPS are the input and output voltage, current and switching frequency.
You either specify the value of the inductance in μH, or you can specify the current ripple as a percentage.
If you want to have a maximum peak-peak value of the current of 400mA for an averaged output current of 1[A], you select 40% and leave the input value for the inductor equal to 0. A corresponding value for the inductance is then calculated.
If you specify the numerical value for the inductance, the waveform of the current is calculated.
To find the inductance at the border of CCM and DCM, specify a value of 200% for the current ripple.
Numerical evaluation of inputs
An input value has to be provided, but can be replaced by an expression, for example 0.5*12 for an output voltage or 20/3.3 for an output current.
Using parameters as input variable
You can use the input variables as a parameter in an expression, to make the input dependent. For example the first input would be Vin being equal to 10 volts. The output voltage could then be written as 0.5*Vin for an output voltage of 5 volts. In this way you can scale parameters.
Calculation
Simply press the [Enter] key on your keyboard or select the [Calculate] button below the numerical input form.
Graphical and Numerical results
The short form of the numerical results is always presented at the top of the Graphical results. Opening the tab [Numerical Results] will give a more detailed overview and explanation of the numerical results.
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