initial spike in Buck coverter output

[nachiket103]

Dear ALL,
I am using TLE7368E buck converter IC for my product.
I am getting very strange problem here.
I am getting spike of 2.5mS before actual output voltage rise and this is causing malfunctioning of my micro controller.
pls. find attached waveform image.
on the evaluation board of IC, this kind of problem is not present.
kindly help me out.

 

[FvM]

I wonder how the steep input voltage rise is achieved? Also I can't relate the waveform voltage levels to the shown circuit with 5.5V output.

 

[nachiket103]

Dear FvM,
Thank you for ur corrections.
I am really sorry abt d waveform.
this waveform is at VCC_3.3.
but unfortunately same waveform is observed at output of buck with max voltage level of 5.5V.

 

[nachiket103]

Dear All,
i am getting waveform at the output of buck converter as attached.
I am not able to determine why this kind of waveform is coming.
kindly help me out.

 

[kanni1303]

i think in basic buck converter has spike in initial starting, so that only moved to cuk or sepic... pls consider that also....