Switch Realization for DC-DC Converters 1
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18 (1)diode off, v(t) negative, i(t) is zero (2)i(t) increases to positive, charging the junction cap., diode becomes forward biased. (3)diode on (4)turn off diode, but the diode remains on while minority charge present in p-n - junction. (5)until all minority charges (Q r ) emoved, then diode is off, i(t) =0 a peak value due to lightly doped n- region exhibits large resistance trtr reverse recovery time
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26 MOS from ON to OFF Diode from OFF to ON
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28 Transistor from OFF to ON Diode from ON to OFF Switching loss
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38 Summary
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