about tl7660

pan5313 pan5313

Above is my circuit, is there something wrong with it?

the level of VCC9.0_ISO jump between 7.24v and 5.82v raddom with load about 20-30ma.

random

0 Ron Michallick over 11 years ago

Pan5313,

The circuit appears to be correct. The first step in trouble shooting a switching supply is to check the switching node.

Can you provide a waveform at the anode of D10?
The waveform at U9 pin 2 may also be helpful.

0 pan5313 pan5313 over 11 years ago in reply to Ron Michallick

wave of U9_PIN2

zoom in

wave of D10's anode

0 pan5313 pan5313 over 11 years ago in reply to Ron Michallick

the reason I have found. L10 should be removed, then short it.

thanks.