Provide Simulations for standard DC/DC converter Types

It would be good to include a simulation for standard DC/DC converter topology's including Buck, Boost, Buck/Boost etc

by eamonb
June 22, 2012

Here's an open-loop toy buck converter that simulates:

Mods / improvements welcome!

by mrobbins
July 13, 2012

Here's a generic Voltage Mode Buck (step down) converter.

Even with the recent solver and simulation speed improvements in CL, simulating switch mode power supplies can be very slow. Therefore this circuit is very much simplified and behaviourally modelled - rather than using detailed device models - so that it runs as fast as possible in CL.

It comprises:

Reference voltage with soft start.

Voltage error amplifier.

Pulse width modulator (sawtooth generator and comparator)

Type 3 loop compensation supplied by Rc1, Cc1, Cc2, Rc3 and Cc3 (there is no Rc2!).

Note that:

i) Loop compensation is not optimised.

ii) You will have to calculate component values for your own application.

Simulate > Time Domain > Run Time-Domain Simulation

by signality
August 03, 2012

Hi Pretty Nice Sim. Models here !Every one has considered Buck , Boost and Buck Boost but I think one Converter is still missing out which is CUK converter. In Cuk Converter Voltage at output can be greater then or less then of input but output voltage's polarity is negative of that input !


by colin79
October 22, 2012

I have sims for Cuk, SEPIC, Zeta and Inverse Zeta but last time I tried them, they did not run well in CL. As the solvers in CL have improved since I first ran them, I'll have another go with them if I get time ...

The clever bit with the Cuk family converters is not the circuit as such, it is how to compensate them.

They are about 3 orders of magnitude harder to compensate than Buck, Boost or Buck-Boost and there are several very serious gotchas in their design.

Voltage Mode (VM) Cuk family converters don't play as well as Current Mode (CM) but running CM converter sims is pushing CL right to it's limits at present.

CL also lacks the ability to start plots at times other than t=0:

by signality
October 22, 2012

I'm having a difficult time understanding if the transformer model(s) in CL can be used in flyback configuration. I know the dots appear on the same side, so I wire the diode on the opposite side to (seemingly) get the correct on/off transfer characteristic but at the present moment I am not 100% sure what I am simulating is close to real-world.

by adampasternak
May 30, 2013

This might help:


The CL transformer symbol can be confusing. The series of circuits: attempt to provide help on understanding how to use and understand the transformer symbol in CL.

attempt to provide help on understanding how to use and understand the transformer symbol in CL.

by signality
June 01, 2013

Hi. Does anyone have a working simulation for a Current Mode Boost converter ? I am trying to debug a stability issue with a boost converter that is regulating the input current .

by eamonb
June 08, 2017

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