| ??? 09/04/02 20:00 Read: times |
#28592 - RE: Do I need a resistor in this circuit |
Edgar is right, you don't need a resistor between emmiter and ground in this configuration. But now... more amateur question time!
What if the emitter were used to drive the motor directly (common-collector / emitter-follower), instead of taking the output from the collector? The difference I can tell of is that the operation would be reversed (which can be easily compensated by complementing the signal),there will be the 0.7 V drop across the transistor and higher current gain. I am aware of comparison between the various transistor configurations, I just wish to know the advantage of the Common-Emitter over the Emitter-Follower in this application. Wouldn't higher current gain be needed to drive a motor? In fact I'd say cascading would be needed...What am I missing? Sorry if this is too newbie, but I need to get back in touch! :-) kundi |



