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5.1: Introduction

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    As we saw in the preceding chapter, a bipolar junction transistor requires a forward-bias of the base-emitter junction and a reverse-bias of the collector-base junction in order to operate properly. One of the prime BJT parameters is the current gain, \(\beta\). It can have a considerable impact on the operation of the circuit. Unfortunately, \(\beta\) also varies with changes in temperature, collector-emitter voltage, etc., and this can lead to circuit instability. In this chapter we shall investigate a variety of circuit topologies to bias the BJT, always with an eye toward stability.

    This page titled 5.1: Introduction is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by James M. Fiore via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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