Switching Losses Switching Power Pole Switching Device I OUT V IN R ON Ideal Diode (for now..)

A B Turn-On Characteristic V sat = R DS(on) I o Off Condition Carrier concentration established in Depletion region On Condition

t t d(on) t ri t fv A B V IN I OUT V SAT Switching Device Behavior with Ideal Diode: Turn “On” Switch Voltage Switch Current Diode Current

t t d(on) t ri t fv A B V IN I OUT PdPd  U ON Switching Loss On-State Loss V SAT I OUT t c,on

D C V sat = R DS(on) I o Turn-Off Characteristic Off Condition Reverse E-Field established in Depletion region On Condition

t t d(off) t rv t fi C D V IN I OUT V SAT Switching Device Behavior with Ideal Diode: Turn “Off” Switch Voltage Switch Current Diode Current

t t d(on) t rv t fi C D PdPd  U OFF Switching Loss On-State Loss t c,off V IN I OUT V SAT I OUT

Switching Loss Frequency Dependency: f s On-State Loss

Example: V IN = 50 v I OUT = 15 A f s = 100 kHz T c,on = 75 nS D = 0.4 T c,off =35 nS R DS(on ) =.03  Find switching losses