f their various "talents." So what we'll attempt to do in this space is set you on the road to enlightenment. We won't get into the composition of the device, but instead concentrate on biasing characteristics as they relate to circuit design. But, before we begin any discussion of diode circuit design, we must first discuss current flow. That's because semiconductor diodes are much easier to control with a bias current, than with a bias voltage.As you already know, the electron current theory states that electrons flow from a negative point to a positive terminal. Although electron current flow is useful to understand the physics of the device, it is rather awkward when reading schematic diagrams. Ben Franklin originally theorized that current flow was from the positive terminal to the negative terminal. That theory is called conventional current flow. You'll notice that the arrows used in all semiconductor symbols point in the direction of conventional current flow, which we will use here, rather than electron current flow. Those facts allow us to describe a current generator circuit by its function: a current source would supply current from its positive output terminal to a load, which is, in turn, connected to a negative terminal. A current sink would draw current to its negative terminal through a load, which would be connected to a positive source. A current pump could perform either function....
