Implementation of Power-Efficient Class AB Miller Amplifiers Using Resistive Local Common-Mode Feedback

Common mode stability in fully differential voltage feedback CMOS amplifiers

In this study consideration is made of the common mode (CM) behavior of two-stage fully differential amplifiers in voltage feedback connection. In particular, interaction between internal CMFB circuitry and the external feedback network is investigated in order to highlight a possible operating point instability condition, due to the presence of a positive feedback loop. Two alternative CMFB to...

Class-E RF Power Amplifiers

This article is based on “Class-E High-Efficiency Power Amplifiers, from HF to Microwave,” Proceedings of the IEEE International Microwave Symposium, June 1998, Baltimore; and “ClassE Switching-Mode High-Efficiency Tuned RF Microwave Power Amplifier: Improved Design Equations,” Proceedings of the IEEE International Microwave Symposium, June 2000, Boston; both by Nat Sokal, © IEEE 1998, 2000.—Ed.

Common Base Transformer Feedback Norton Amplifiers

For about a year I have been experimenting with extremely high intercept amplifiers using 2N5109 bipolar junction transistors (BJTs). These kinds of amplifiers, known as common base transformer feedback (CBTF) amplifiers, and also known as common base noiseless feedback amplifiers, if properly designed and used, offer MW DXers (and SW DXers, though their needs are not as extreme as MW DXers) am...

Power Scaling Fiber Amplifiers Using Very-large-mode-area Fibers

Class-D Audio Amplifiers with Negative Feedback

There are many different designs for audio amplifiers. Class-D, or switching, amplifiers generate their output signal in the form of a high-frequency square wave of variable duty cycle (ratio of on time to off time). The square-wave nature of the output allows a particularly efficient output stage, with minimal losses. The output is ultimately filtered to remove components of the spectrum above...