Nov 9, 2011 #1 K Khan740 Junior Member level 2 Joined Jan 17, 2011 Messages 21 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,281 Activity points 1,401 Hi, Why there is phase change in Common Emitter Amplifier?
Nov 9, 2011 #2 Syncopator Full Member level 6 Joined Dec 15, 2010 Messages 367 Helped 70 Reputation 140 Reaction score 66 Trophy points 1,308 Location N.E. Lincolnshire U.K. Activity points 3,395 There isn't. There is an inversion. When the base of an NPN transistor goes positive the base-emitter current increases, and so, therefore does the collector current. The increase in collector current produces a larger voltage drop across the collector load. The collector voltage therefore goes less positive. And vice versa for a negative change at the base. In a PNP transistor the action is similar, but the polarities are opposite to the NPN case.
There isn't. There is an inversion. When the base of an NPN transistor goes positive the base-emitter current increases, and so, therefore does the collector current. The increase in collector current produces a larger voltage drop across the collector load. The collector voltage therefore goes less positive. And vice versa for a negative change at the base. In a PNP transistor the action is similar, but the polarities are opposite to the NPN case.