- An ideal voltage source is a circuit element that maintains a prescribed voltage across its terminals no matter how the current flows through it.
- An ideal voltage source has zero internal resistance. Therefore it cannot be shorted.
- The current in an ideal voltage source can be zero if no loads are connected to the source.
There’s two types of voltage sources:
- independent, like (a)
- and dependent (or sometimes called controlled) voltage sources, like (b) and (c)
- An ideal current source is a circuit element with a prescribed current flowing through its terminals no matter what the voltage across the terminals is.
- In theory, an ideal current source has infinite internal resistance.
- The arrow in the circle shows the reference direction of the current in the source.
There are two types of current sources.
- Independent current sources, like (a)
- and dependent current sources, or controlled current sources, like (b) and (c).
- (b) is a voltage controlled current source, or VCCS.
- (c) is a current controlled current source, or CCCS.