# Circuit Theory/Transistor symbols

## Circuit symbols

There are lots of different types of transistors. The most popular is a
MOSFET and within this family there are lots of possibilities. The goal
right now is not to understand the differences and what all the lines
mean. Look at them and see that normally there are three wires
associated with them.

  ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------- ---------------------------------------------------------------- ---------------------------------------------------------------------------- -----------
  ![](JFET_P-Channel_Labelled.svg "JFET_P-Channel_Labelled.svg"){width="80"}   ![](IGFET_P-Ch_Enh_Labelled.svg "IGFET_P-Ch_Enh_Labelled.svg"){width="80"}   ![](IGFET_P-Ch_Enh_Labelled_simplified.svg "IGFET_P-Ch_Enh_Labelled_simplified.svg"){width="80"}   ![](Mosfet_P-Ch_Sedra.svg "Mosfet_P-Ch_Sedra.svg"){width="80"}   ![](IGFET_P-Ch_Dep_Labelled.svg "IGFET_P-Ch_Dep_Labelled.svg"){width="80"}   P-channel
  ![](JFET_N-Channel_Labelled.svg "JFET_N-Channel_Labelled.svg"){width="80"}   ![](IGFET_N-Ch_Enh_Labelled.svg "IGFET_N-Ch_Enh_Labelled.svg"){width="80"}   ![](IGFET_N-Ch_Enh_Labelled_simplified.svg "IGFET_N-Ch_Enh_Labelled_simplified.svg"){width="80"}   ![](Mosfet_N-Ch_Sedra.svg "Mosfet_N-Ch_Sedra.svg"){width="80"}   ![](IGFET_N-Ch_Dep_Labelled.svg "IGFET_N-Ch_Dep_Labelled.svg"){width="80"}   N-channel
  JFET                                                                         MOSFET enh                                                                   MOSFET enh (no bulk)                                                                               MOSFET dep                                                                                                                                    
  ---------------------------------------------------------------------------- ---------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------- ---------------------------------------------------------------- ---------------------------------------------------------------------------- -----------

