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ArcticMyst Security by Avery

Help with buck regulator

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Mar 2, 2011
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I am working on a buck regulator using a UC3844n IC
I have a couple questions

1)Can I use the current sense pin on the uc3844 to directly regulate the output current? how?

2)The circuit seems "slow" right now, like when i go from a small load to a large load the voltage drops and takes a second or so to come back up, same the happens when i remove the load, but the voltage jumps up.
I think it is because I have the wrong resistor/capasitor going from pin 1 to pin 2, what should I have for the resistor/capasitor?

http://www.ti.com/lit/ds/slus223c/slus223c.pdf

circuitcd.jpg
 





Joined
Mar 2, 2011
Messages
692
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Thanks Cyparagon, I'll try out some smaller caps later today when I have acces to an oscope.

For the current regulation, it looks like when a voltage on pin 3 is > 1 V current limiting starts happening.
I want this thing to be capable of around 10 amps, but I want it variable, (so unless a 10w 1 ohm potintiameter exits...)
I thinking of using a .1 ohm resistor and an op-amp with variable gain as shown
Would this work/ is there a better way to do this?

currento.jpg
 
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