Transistors

How a NPN Transistor Works

                 Collector (C)
                     |
                     |   (High voltage input)
                     V
                +-----------+
                |           |
                |     C     |
                |     |     |
                |   |/      |
Input to Base → |---|       |
  (small        |   |\      |
   current)     |     |     |
                |     B     |
                |           |
                +-----------+
                     |
                     V
                 Emitter (E)
                (to ground)

Current Flow:

           HIGH VOLTAGE
                 |
                 v
       Collector (C)
             |
             |   <--- Large current flows C → E
             |
        --------------
         TRANSISTOR
        --------------
             |
 Base (B) →  |  <--- Small current enables conduction
             |
             v
           Emitter (E)
                 |
                 v
               GND