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ADuM3223

Question asked by kwing54 on Aug 26, 2015
Latest reply on Aug 27, 2015 by kwing54

In the driver ckt attached, there is 1.9mA flowing from the 12V bias in the pump diode with the input side disabled (DIS pulled high to 3.3v).  This current outputs from the GNDA pin, to the source of the high side FET and through the body diode, and out the HV input rail which is dead. The HV source comes and goes, and this current is undesirable in this application.  With 4 drivers in the system, for this  quad sync buck converter, there is 7mA flowing out of the HV bus input (all BUCKOUTs are paralleled).  Is there any way to kill this current when the part is disabled?  Or do I have to put a high side switch on the 12V  feedingVddA/B?

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