UC3525A: Can you please resend the link regarding BOOST application notes in this link? Thank you!

Iiujin,

The link you are referring to is 13 years old and is pointing to National Semiconductor website. As you know TI acquired National and so the document you are searching for is likely located someplace on TI.com but it is also possible it no longer exists and it definitely cannot be found from the link you are asking about.

If this document were a TI app note, you could identify it through the link because TI uses "SLU" prefix to identify such documents and you could then search for the SLUxxx number. In this case there is no such number available. 

Regards,

Steve

You can search TI.com, Google or YouTube and find many excellent sources. 
Steve 

You will need to use whatever search/research tools you have available. The boost converter is a very popular basic topology for seed in many applications. 

steve

Your question was about a link that is no longer valid. As Steve mentioned, that National Semi content has likely been absorbed within TI.com. I performed the search and this is virtually all technical articles and app notes TI has on boost controllers.

https://www.ti.com/sitesearch/en-us/docs/universalsearch.tsp?langPref=en-US&searchTerm=boost&nr=1439#q=boost&sort=relevancy&numberOfResults=100&f:technicalDocuments=[Technical%20article,Application%20note]

For specific help, TI's Power Stage Designer is a very useful resource: https://www.ti.com/tool/POWERSTAGE-DESIGNER

Regards,

Ray

Thank you