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H-bridge: so many different resistances!!!

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New Member
I have been reading along and looking for the best way to make an h-bridge (6A start, 3A continuous). Having some trouble finding the all-ready chip in my city, I decided to buy the descrete components. Found this website pretty useful:
so I bought two TIP141 and two TIP145 (instead of the TIP12* for more current) and the PN2222 transistors to start playing with them on my breadboard. At first I disregarded the resistors (there are so MANY!!! :!:) but along came this website:
that ruined all the fun and told me: you dont have a clue what you are doing!!! :?
so here is the question: do I change the values of those resistances? If yes, to what? (I am using the regular Ni-CD rechargable battery @7.2 V)

(I have been thinking about it: was not it easier to use four NPN transistors and avoid the trouble with the very confusing arangements of the PN2222s or is there less power loss this way?)

Something else. I have to heatsink the TIP14* transistors; what is the isulator to use: is is some kind of paper, paste, what is it anyways, what is the market name if I should buy it.

Agent X

New Member
Hi there, i've taken a look at the site you've posted and I've had trouble tinkering with the resistors before, but they are needed in or to drive the load. I dunno if this is much help but i've included the h-bridge design that I modified as in the transistors and resistors to suit my need, hope it helps. Another thing is I am not clear why u would want to remove the current resistors u have is it because you'er not getting the current u need?


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