IR1167(A,B)S

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© 2013 International Rectifier

Nov 6, 2013

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

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.

During the SR FET conduction phase the current will decay linearly, and so will VDS on the SR FET.

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 reset as soon as

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T1

T2

T3

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