Witte J. Dynamic Offset Compensated CMOS Amplifiers 2009

Textbook in PDF format

CMOS amplifiers suffer from relatively poor offset specifications. Since the 1980s techniques have been explored to calibrate for this offset, or to let the amplifier itself compensate for its offset in some way or another. This latter approach is often done dynamically during operation of the amplifier, hence the name “dynamic offset compensation”. This thesis describes the theory, design and realization of dynamic offset compensated CMOS amplifiers. It focuses on the design of general-purpose broadband operational amplifiers and instrumentation amplifiers.
Two distinguishable offset compensation techniques are described in chapter 2: auto-zeroing and chopping. Several topologies are discussed, in chapter 3 which can be used to design broadband dynamic offset-compensated operational amplifiers as well as instrumentation amplifiers, which are described in chapter 4. Four implementations are discussed in this book: two low-offset broadband operational amplifiers in chapter 5, and chapter 6 discusses a low-offset instrumentation amplifier, and a low-offset current-sense amplifier, which can sense battery currents at a 28V rail