Abstract
In this article, a new bias current regulation circuit of a one-stage bipolar and Filed Effect Transistor amp is described. How the FET achieves high precision and simplicity by means of a combination of feedback error amplifier with a bandgap reference is explained.
Introduction
Regulating current through active devices sets the output level in a drive circuit. Figure 1. Below shows typical application of these active devices. Qo I used as a FET rather than a BJT. In a limiting amp, the Qo acts as a switch and the output signal level is proportional to the bias current. The gain ...