Determination of voltage source values in modern biasing techniques of analog circuits

In modern biasing techniques for analog circuits, voltage sources are introduced that do not need to be very accurate. Instead their value should only lie within a certain range. In this paper, it will be shown that this freedom can be used to obtain a more efficient design with respect to the number of level-shifts required. An expression for the minimum number of required voltage sources is derived after an analysis based on loop-equations. This expression is used to establish design rules. Finally the biasing of an amplifier will be shown as an example.