Please contribute some ideas

 

I need some schematics about connecting the KA3834B with boost converter,please help me!

 

Searching turns up nothing about that device. Perhaps a bad number?

 

you will find datasheets at this address for the device in question.
http://www.datasheetarchive.com/KA3843-datasheet.html

it is equivalent to the uc3843, here is TI's page on it
http://focus.ti.com/docs/prod/folders/print/uc3843.html

looking through the data sheet the only full circuit given was for an offline flyback converter.

however there were quite a few useful pieces of information on setting slope compensation, soft start circuits and the like.

 

Fairchild Semiconductor has this part also:
http://www.fairchildsemi.com/pf/KA/KA3843B.html

Looking through the 2nd link that S_lannan posted, found this abstract:
http://focus.ti.com/analog/docs/techdocsabstract.tsp?familyId=398&abstractName=slua143
Direct link to document: http://www.ti.com/litv/pdf/slua143

If you go to this page:
http://focus.ti.com/docs/prod/folders/print/uc3843.html
and scroll down to "Technical Documents", about 3/4 of the way down, you will find a slew of application notes.

 

thank u for this information