Hi Bosheng:
It is pretty well known that a traditional analog controlled boost will require a jump diode to precharge the output capacitor as shown in Figure 25 of SLUU885B–March 2012–Revised July 2012
PFC EVM user's guide.
But why in digital control do we need diode D2 in Fig 25( see attached screenshot of Fig 25 for convenience)?
Can the code not be made to start off Gate drive upon power ON ?
Furthermore, if the topology used has isolation, surely you do not want to add D2, neither if it is a bridgeless topology. Lastly, we have a case where output is isolated 48V.
This will destroy the " galvanic isolation" feature altogether.
If we do not put D2, what methods do you suggest to begin a "slow start" process for nonisolated, isolated and 48V versions?
We will have all these versions in our products.
And cannot use D2 in any of these cases.
