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What is the difference between CCM and DCM in flyback topology

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KwangHeon

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I'm studing the flyback SMPS.
The documents about flyback say about the difference between CCM mode and DCM mode, for example, primary and secondary current, transformer inductance, etc.

But I cannot find any information about the difference in the topology.
What is the difference?
Are they same in topology, only difference in transformer inductance?
Or difference in the controlling IC?
 

PHP: 
  DCM is much popular for SMPS design because of its simple transfer function characteristic 
and good line and load regulation. Most importantly the maximum output power can be set at a constant
 value and no power overshoot during fault. However, CCM can provide the higher efficiency which is
 required by more and more applications. In CCM operation, both of the peak current and RMS current are
 lower than that of DCM operation. Although its overload protection threshold varies with the input voltage,
 CCM operation is still attractive for the applications with high efficiency requirement.
quoted from

ref
 

Sorry, I haven't thought my question was ambiguous.

I'm referring '2010-2011 Power Supply design semiar' ( **broken link removed** ) page 1-1 to 1-5. CCM and DCM was explained with the same schematics at page 1-2.
At the Fairchild App Note AN4137 ( https://www.fairchildsemi.com/an/AN/AN-4137.pdf ), CCM and DCM was explained with the same schematic at page 1, it says FPS(Fairchild Power Switch) works as DCM at light load and as CCM at heavy load.
There are many documents for the pros and cons of CCM and DCM.
But I don't know what's the difference in schematics. I can easily find sample schematics for flyback, but I cannot find any explanation whether it is CCM mode or DCM mode (for example ST's appl note AN2097, 10W flyback using VIPer22A).

I searched google for the topology difference between CCM and DCM, but failed.
 

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