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本帖最后由 超級狗 于 2017-6-2 11:55 编辑
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) {2 U6 k# u8 O0 D, |Control Logic
1 U3 y( E1 O2 e; S4 |Control logic block detects whether high side MOSFET is turned off by monitoring (UGATE - PHASE) voltages below 1.1V or PHASE voltage below 2V. To prevent the overlap of the gate drives during the UGATE pulls low and the LGATE pulls high, low side MOSFET can be turned on only after high side MOSFET is effectively turned off.
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5 J1 Q% w& o- ?0 }% \- L( z6 Y: DHigh Side MOSFET 和 Low Side MOSFET 的開關控制是不會重疊的,在 High Side MOSFET 已經關閉,但 Low Side MOSFET 又尚未開啟之前,右側電感的迴路只能透過 D2 的 Body Diode 導通,這段時間被稱為 Dead Time。
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$ E& z2 ^' x0 f由於 Body Diode 會有個順向導通壓降(Forward Voltage),所以這段時間會有個叫 Low Side MOSFET Dead Time Body Diode Loss 的損失。
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- f+ i" g( c6 I* f它只是說明這個關係,沒特別的意思!
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