New port modeling for analog circuit biasing design

Abstract

A new port modeling technique is presented for biasing of analog circuits. The technique uses fixator-norator pairs to pair the biasing design criteria with the power sources - locations and magnitudes - required for the biasing. Because of the operating points (OPs) being specified the technique allows the designer to linearized the circuit not only for the performance (AC) design but also for the large signal biasing design. It is shown that the fixators - nullators plus sources - keep the biasing criteria fixed during the analysis; whereas, the norators act as the place holders for the DC supplies or for the power conducting components. The rules to engage in circuit analysis with fixator-norator pairs are discussed and numerous pitfalls in this category are specified. Finally, two design examples are worked out that clearly demonstrate the capability and power of the proposed technique for biasing of any analog circuit.