Electronics > Projects, Designs, and Technical Stuff
Which injection transformer for feedback loop measurements?
(1/1)
jmw:
I'm trying to follow the procedure in AN-1889 for measuring the feedback loop gain in a power converter. A transformer is used to couple a function generator signal across a small resistor without passing DC, but I'm not sure what kind of transformer to use. The note says "There are special transformers for such measurements available, which offer a very flat voltage transmission over a wide frequency band." What kinds of commercially available transformers specifically fit this bill? I was browsing Digikey and thought maybe things under current-sense transformers or pulse transformers seem like they could work. Has anyone done this and have recommendations?
uer166:
Got this guy at work not long ago, can't comment on how good it is, but it's designed for your application: https://www.picotest.com/products_J2101A.html
jmw:
Did some searching, looks like this topic has come up before. Seems the options are that Pico-test unit or similarly priced, or homebrew it. Guess that's another project to put on the board  :-DD
Mechatrommer:

--- Quote from: uer166 on April 23, 2020, 06:09:45 am ---Got this guy at work not long ago, can't comment on how good it is, but it's designed for your application: https://www.picotest.com/products_J2101A.html
--- End quote ---
$525 can buy a lot of stuff... did the OP created this thread due to this thread? https://www.eevblog.com/forum/testgear/injection-transformers-bode-plots-application/?topicseen Jay_Diddy_B uses much cheaper Wurth 744 229 Common Mode choke. ($2.46 USD Qty 1 Digikey) maybe testing and try and error with much cheaper transformer first can give us much lesson before we can spend anything near $500 bucks. if i want to do real life testing on this, i will start first with my function generator and/or if necessary wind my own HF transformer with available ferrite core in my stock. ymmv.
Navigation
Message Index
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod