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LM5175: buck-boost circuit MOS are very hot

Part Number: LM5175LM5175

Hello,

I've  designed a LM5175 buck-boost circuit ,19-28V  input,24V/5A output.

while  I test the circuit,found the MOS are very hot even unloaded .

The output voltage is OK.But the input current looks weird,test results as below:(1.buck: input 27.5V/1A ,OUTPUT 24V/160mA  2.boost:input 19V/2A,output 24V/160mA.)

The load mode setting is C R mode-140 Ohm.Please advise what's wrong with this circuit .wave form as below: