Author Topic: Higher Current LM2576 Buck Converter  (Read 1949 times)

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Offline wlamb02

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Higher Current LM2576 Buck Converter
« on: July 22, 2015, 09:15:56 pm »
I want to modify the LM2576 to output a higher current and generate less heat using a mosfet with a lower Rds(on). Can I just connect the gate to the output? Here is the block diagram http://www.ti.com/lit/ds/symlink/lm2576.pdf#Block Diagram
« Last Edit: July 22, 2015, 09:18:39 pm by wlamb02 »
 

Offline Cliff Matthews

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Re: Higher Current LM2576 Buck Converter
« Reply #1 on: July 22, 2015, 09:25:23 pm »
That's odd, someone else asked that today.. a going trend maybe? I have a bucket of TOP200's I'd like to try doing the same thing with.
https://www.eevblog.com/forum/beginners/lm2577-high-current-with-mosfet/
 

Offline commie

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Re: Higher Current LM2576 Buck Converter
« Reply #2 on: July 22, 2015, 10:10:06 pm »
The chip you are using has been specially designed for a few parts as possible, hence the pass transistor switch resides on chip and its terminals are not available for output. May I suggest you try a MC33063 chip which will allow you greater design flexibility, the pass transistor are also on chip but the collector/emitter are available for alternate configurations.

I used this chip to drive a mosfet awhile back no problem but for other reasons I ended up using a darlington instead.

Note, mosfet rds_on figures are a little bit misleading.

Hope that helps

 
 


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