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Old 03-18-2012, 04:58 PM   #29
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Default Re: Barco LCN-42 No Power

Q203 is the power MOSFET mounted on the heat sink right? The Drain voltage is probably in the 100VDC or higher, so when it shorted out that will voltage will be developed on that resistor and blow up that resistor, the current feedback circuit is connected to the Source of the MOSFET will be present at the Current feedback input pin of the SMPS IC also and could have damaged the input pin of the IC as well, I would Ohm out the SMPS IC also. Do you know what the IC number is for this section of this circuits? The Gate connection should be hooked up to some resistors and Diode back to the SMPS IC output put drive, check that pin also.
See some example PDF, PIN3 is the CS (CURRENT SENSE) pin.
Attached Files
File Type: pdf FAN 5541 SAMPLES.pdf (48.3 KB, 16 views)

Last edited by budm; 03-18-2012 at 05:17 PM..
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