Pulse and Digital Circuits

1.2 CURRENT AND VOLTAGE SOURCES

Normally either ac or dc sources are used as current and voltage sources. A source can be either a voltage source (Thévenin source) or a current source (Norton source). An ideal voltage source should have zero internal resistance so that when current is drawn from the source, there is no voltage drop across the internal resistance of the source and the entire source voltage is available at its output terminals. Similarly, in a current source, no appreciable amount of current should flow through the internal resistance of the generator and the entire source current should flow through the load. For this, the internal resistance of the current source should ideally be infinity.

Figure 1.1(a) shows a practical voltage ...