LM339 Sink to Source Converter???

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Krumlink

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I am building a secret project, codename: KAPTR v1.0, and The Comparator in it can only sink current, not source it, so therefore I need to figure out in order to get the H Bridge working for it how to convert the Sink (negative output) into source (positive output), essentially I need to invert the negative signal. Do you have any ideas on how I can approach that? I was thinking of using a PNP Transistor on the LM339 outputs and have that output a Positive signal, but would that work if I then used that as a positive output?

Thanks
 
Yes. The open collector output stage of the LM339 can be used to turn on a PNP stage. Current flows from the supply to the emitter to the collector to the motor. The base needs to be pulled up to the motor supply and a limiting resistor from the base to the LM339 output will set the maximum current through the motor.
 
Thanks a lot, was testing it and I put one on there for testing, and It works great. Thanks a lot. I just have to mount a few boards and I will post more soon
 
Well then it would make the H bridge (that I am using) stall, because it would turn the high side and low side on at the same time, causing a stall and a short circuit, a easy way to destroy it
 
Krumlink said:
Well then it would make the H bridge (that I am using) stall, because it would turn the high side and low side on at the same time, causing a stall and a short circuit, a easy way to destroy it
Click to expand...

So your H-Bridge is badly designed as well?.
 
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