Hello I'm new to this forum..
I'm in need of desperate help!
Posted is a schematic of a P.W.M circuit that is powered by a 12V DC PS.
As the pot. is turned from 0-50 the motor is supposed to spin CW, and 50-100% CCW.
This circuit is not working!
For the transistors, instead of the ones in the schematic i have replaced them with the NPN CB547B and the PNP C557B
Am I using the wrong transistors? Am I missing anything?
I am not allowed to use another 555 timer. I only have to use the H bridge format.
I'm in need of desperate help!
Posted is a schematic of a P.W.M circuit that is powered by a 12V DC PS.
As the pot. is turned from 0-50 the motor is supposed to spin CW, and 50-100% CCW.
This circuit is not working!
For the transistors, instead of the ones in the schematic i have replaced them with the NPN CB547B and the PNP C557B
Am I using the wrong transistors? Am I missing anything?
I am not allowed to use another 555 timer. I only have to use the H bridge format.
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