Practical example: the design of analog amplifiers in the Delta-Sigma modulator system

Abstract

In this chapter, three analog amplifiers that are parts of a hybrid multi-bit Delta-Sigma modulator are designed starting from the system-level specifications. It is demonstrated how to take into account the environment of an amplifier in the system, determine an appropriate design testbench, use the design flow described in the previous chapters, and evaluate the results. In each case, the fully differential folded cascode OTA is chosen as the most suitable topology to fulfill high gain and high gain bandwidth design requirements. However, topology variants were necessary in order to achieve the additional design requirements, whereas the procedural design scenario was the same for all three amplifiers.