ABSTRACT
This chapter begins with answering a fundamental question as to the need for having a transient component in the response of a circuit. It turns the attention in to switched circuits; that is, circuits in which the movement of a switch applies an input to the circuit or changes the circuit configuration. The chapter analyzes the responses of prototypical first-order and second-order circuits to a step input and related to the impulse response. The general case of switched circuits that have relatively complicated connections of resistors, inductors, and capacitors, and which may include linear transformers and dependent sources, is best handled using the Laplace transform. The discussion of switched second-order circuits is restricted to prototypical second-order circuits, that is, circuits that can be reduced to simple series RLC or parallel GCL circuits. The effective time constant is therefore determined with ideal, independent voltage sources replaced by short-circuits and ideal, independent current sources by open circuits.
