IR11672AS

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© 2009-2011 International Rectifier

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Figure 2: Primary and secondary currents and voltages for DCM mode

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Figure 3: Primary and secondary currents and voltages for CrCM mode

CCM Turn-off phase

In CCM mode the turn off transition is much steeper and dI/dt involved is much higher. The turn on phase is

identical to DCM or CrCM and therefore won’t be repeated here.

turning the gate off. The turn off speed is critical to avoid cross conduction on the primary side and reduce

switching losses.

Also in this case a blanking period will be applied, but given the very fast nature of this transition, it will be