help regarding polarity reversing switch.

i need to know abt an element that changes the polaritry of any motor/circuit when a pulse is passed to it.

suppose initially it is +......-.
when the pulse is passed momentarily polarity changes to --.........++.



please reply soon .i need it urgently.

Look for a circuit called 'H-Bridge', it's fairly common and not too complex to build. Can also be found in IC form. A relay might also be used, but depends on the application.

You gave no specific information, so this is likely the most detail you can expect. It would have helped to know what the application is, the supply voltage, motor specs, expected load.

Zaidimam,
Please don't make multiple posts for the same topic. Keep your questions in a single thread then you will see that you need a flip-flop circuit from the reply to your other post that controls the H-bridge reversing circuit in this post.

Sorry about that, didn't notice there were multiple threads. I usually don't even bother reading them. It's too confusing to decide which one to reply to, and they are usually a student project, with only a day or two to complete something they were assigned months before...

Now Nigel will need to try and combine these, delete them, or some way clean up the mess. Should probably just delete them all, and let the OP start over in a single thread.