Hello,
This circuit operated under test on five different boards, recently one of them showed the following situation:
-When I turn on the circuit it runs fine, 48V input and 12V output.
-If the load is smaller than something around 200mA it still work great.
-When I apply a load bigger than approx. 200mA the readings go crazy, as I will show on the oscilloscope images below
-If the load is under 200mA, the behaviour is 100% normal
-Before the problem started, the load on the LM5005 was 0.5A
The readings on the oscilloscope are from top to bottom:
CH1 Max
CH1 Frequency
CH1 Peak to Peak
CH1 Average
Reading of the Feedback pin:
Reading outuput after the inductor (with the output capacitor):
Reading of the output before the inductor:
Picture of the circuit:
The circuit is almost identical to the WEBENCH Simulation and the PCB has a pretty good dissipation. Anyone has a guess on what could be the problem?
Thanks in advance.
