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LM7480-Q1: Part misbehave

Part Number: LM7480-Q1

Tool/software:

Hello...

We have problem in our design as part doesn't work as expected. I have already replaced part but have same issue.

The problem is that we don't get output at all.

The attached is part of schematics and image of chip marking.

I have measured all voltages and here is result:

With test condition with X51 set to deliver 0 V to EN/UVLO the measured voltage at pins are:

Item Voltage Our opinion
VBAT 12.02 V Supply voltage
VS, VSNS, SW 12.02 V As should be
OV 0.40 V Overvoltage not triggered (Under 1.13 V)
OUT, A 0.00 V OK as EN/ULVO is low
HGATE, DGATE 0.00 V OK as EN/ULVO is low
C 0.00 V Excepted as gate is low
CAP 11.36 V    Probably ok as EN/ULVO is low
EN/ULVO 0.00 V connected to GND

And other set of measurements with test condition with X51 set to deliver 12 V to EN/UVLO the measured voltage at pins are:

Item Voltage Our opinion
VBAT 12.02 V Supply voltage
VS, VSNS, SW 11.97 V    50 mV drop on R59 indicating 5 uA power draw
OV 0.40 V Overvoltage not triggered (Under 1.13 V)
OUT, A 0.00 V Expected as GATE is LOW
HGATE, DGATE 0.00 V It should be around 20V
C 0.00 V Excepted as gate is low
CAP 11.36 V Probably wrong as charge pump should run
EN/ULVO 11.97 V connected to VS

Really don't know what is wrong there so any help is welcome.