I am testing and comparing both a synchronous and asynchronous buck converters. In both versions, I am using ideal switches so there shouldn’t be any parasitic effects from MOSFETs in the simulations. I would expect the synchronous buck converter to have less output switching ripple. Can someone please advise why the synchronous buck converter is displaying much, much greater switching ripple than the asynchronous one?
UPDATE!!! Added capacitor esr values of 8mOhm to both 110 uF capacitors.
Nice! New user restrictions have been lifted. 
Here is the schematic:
Synchronous_Buck_Converter_Compensator_Type_III_2z3p.qsch (28.4 KB)
Thank you.
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You have dead time between switching, but where can the inductor current flow during dead time if there are no body diodes in the switch models? A high di/dt in the inductor can induce a high voltage spike.
Two Solutions
- Add diodes in parallel with the switches if you need dead time. This diode model can have a higher Ron and a finite Vfwd so that primary conduction still relies on the switch rather than the diode, while eliminating the spike condition described above.
- Alternatively, use ideal switching without dead time.
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Awesome! This did the trick. I tested three case scenarios. They say a picture is worth a thousand words. Here are the results.
I wanted to reply about 2 hrs ago, but the system generated this warning: 
As you can see from the schematic, I borrowed the comparator and the deadtime generator from your library and Marco’s. I appreciate your investment for the community at large. 
Your insight has been very invalueable, as it has helped me solve this issue.
Thank you a bunch! 
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