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只是換了顆二極管？是換成哪一顆？
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Diode
6 M' e* K3 a3 K- X( ^/ K' A$ TThe diode is the main source of loss in DC−DC converters. The most importance parameters which affect their efficiency are the forward voltage drop, VF, and the reverse recovery time, trr. The forward voltage drop creates a loss just by having a voltage across the device while a current flowing through it. The reverse recovery time generates a loss when the diode is reverse biased, and the current appears to actually flow backwards through the diode due to the minority carriers being swept from the P−N junction. A Schottky diode with the following characteristics is recommended:' N& F4 R* a; b1 C8 P, l6 k+ I
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+ D {4 X9 q/ b2 W4 T( K2 a" E* V- Small forward voltage, VF < 0.3 V
- Small reverse leakage current
- Fast reverse recovery time/ switching speed
- Rated current larger than peak inductor current, Irated > IPK
- Reverse voltage larger than output voltage, Vreverse > VOUT7 Y: _; m+ e' F3 u" ]4 W3 G
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发表于 2011-9-22 15:40
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发表于 2015-3-9 18:05