problem with viper37LD

[PINI BITON]

Posted on February 29, 2016 at 12:38

Hi

i have a problem

i build ac dc converter based on flyback and i get in outpout sawtooth with rippel 1v 

i should get stable voltage in outpout

input: 110-230Vac,outpot 12v 1A

i used chip viper37LD and isolated feedback

why i get 1v 

rippel  in 

outpout? and how is solve it ?

[M. Palano]

Posted on February 29, 2016 at 13:58

Hello Mr. Pini,

First of all let me thank you for using STMicroelectronics products and our eDesignSuite design tool; you made the right choice.

Regarding the specific problem you are facing, could you, please, add more details together with some screenshot from the oscilloscope?

Best Regards.

[PINI BITON]

Posted on February 29, 2016 at 15:26

i attach pictures

one is the circuit ,and another isscreenshot .

________________

Attachments :

20160229_161753.jpg : https://st--c.eu10.content.force.com/sfc/dist/version/download/?oid=00Db0000000YtG6&ids=0680X000006HzDf&d=%2Fa%2F0X0000000bIX%2FnU4U5e7.Z.wPBNTyG8JkEE9Afr_4l1s4RNia9Ei0TSo&asPdf=false

Capture12.JPG : https://st--c.eu10.content.force.com/sfc/dist/version/download/?oid=00Db0000000YtG6&ids=0680X000006HzAD&d=%2Fa%2F0X0000000bIV%2FPS3_ZMSwj0ZGGlgMW7YnEIzanl.i9F0TFOQl.8EJucA&asPdf=false

[M. Palano]

Posted on March 01, 2016 at 17:39

Hello Mr. Pini,

it seems the circuit is working without a load. Is this the case?

[PINI BITON]

Posted on March 06, 2016 at 08:52

I solve that 

the problem is with the value of R opt(it's relevant for optocoupler)

thank