>It seems tps54350 switcher is so easy to burn! I burn 3, today! what wrong?

Well only you can tell us what is wrong - you haven't provided enough 
information yet.

Does it get hot?
Does it emit smoke?
Does it just not work at all?
What are your test conditions?

>Trying notebook power supply,

So you are trying to make a notebook supply?

>adjusting lm317,

What does an LM317 have to do with a TPS54350?

>hand shaking, each broken one.

What handshaking?

>Although 54350 has good performance as a regulator,
>but such easy to damage is just impractical.

You have had it working? Under what test conditions?

>It is said, tps has all kind of protection, but never work!
>Any suggestion about pwm voltage regulator?

Do you mean the TPS54350 has lots of protection? There are many chips with 
TPS part numbers. No amount of protection will stop it from destroying 
itself if you are using too high an input voltage, or wrong value inductor, 
or wrong FET for the external FET or ...

You need to detail what you have for a circuit, how you built it and how you 
test it.

Did you use the recommended PCB layout and component list, especially 
inductor and capacitors? 

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist