LM7480: V(DGATE) – V(A) only 3V

Part Number: LM7480

Tool/software:

Hi,

  V(DGATE) – V(A)  only 3V, Causing Q1 to heat up.

The customer tested with 30V, VDGATE 33V,HGATE 41V, Q1 heat up,Q2 normal.

Increasing the capacitance CAP to 470nF does not improve either.