what actually amplifies the current in CE mode of a transistor(npn here)? When the input is applied betn emitter and base, the forward biasing causes the electrons to move from source to the emitter say 100 electons. The same 100 electrons move towards the base where very few no. of electrons combine with holes say 2. they move out of the base towards source. so remaining electrons are 98 which move to the collector and out to the output circuit. So where is the current amplification? i have considered the Veb as 0.7 and Vce to be 1.

  • \$\begingroup\$ The input source connected between the base-emitter provide only the base current and the output source (collector-emitter) must provide the rest of the current. So, BJT doesn't literally "amplify" the current into its base.It merely allows a low current (IB) to control the flow of a much larger current (Ic). upload.wikimedia.org/wikipedia/commons/7/73/… \$\endgroup\$
    – G36
    Oct 29, 2017 at 12:11
  • \$\begingroup\$ sorry sir but i didnt get your answer. Would you mind elaborating please? \$\endgroup\$
    – G-aura-V
    Oct 29, 2017 at 12:20
  • \$\begingroup\$ A NPN transistor doesn't have a "source". It does have a emitter, though. \$\endgroup\$ Oct 29, 2017 at 12:41


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