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???
05/07/07 12:38
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#138708 - paralleling chips
Responding to: ???'s previous message
is the equivalent of paralleling transistors.

If you parallel 'transistors' (outputs) in the same chip you can (PLEASE NOTE: the word 'safely' is NOT inserrted here) assume that the transistors are similoar, if not identical and will share the load equally, I never would ASS U ME that, but since "Datasheet says that: For higher currents, outputs can be paralleled" (the link you give is dead) I would ASS U ME that the transistors are matched.

Now, when you parallel outputs in different chips there is no matching.

If you look at schematics for higher current linear supplies, you will see that in series with each parallel transistor is a small 'load equalizer resistor' and when paralleling unmatched drives, such are required.

I would suggest that, instead of trying to 'equalize' drives from differnt chips, you use some mosfets (possibly driven by your chip) to drive the load. Since you do not have 'base and emitter access to the transistors in the chip, it would be fools errand to try to load equalize the drivers, a simple series resistor, will only do a avry small equalizing, if any..

BTW ALWAYS get the datsheet from the manufacturer, other sites may have old, incorrect revisions.

http://www.st.com/stonline/...3/l298.pdf

Erik

List of 3 messages in thread
TopicAuthorDate
8 Amps Driver!            01/01/70 00:00      
   one reason to check for            01/01/70 00:00      
   paralleling chips            01/01/70 00:00      

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