What This Document Is
This document represents the eighteenth lecture from the Introduction to Microelectromechanical Systems (MEMS) course (ELENG 247A) at the University of California, Berkeley. It focuses on the critical topic of Analog-to-Digital Conversion (ADC), a fundamental building block in many electronic systems, particularly those involving MEMS sensors and interfaces. The lecture delves into the intricacies of converting continuous analog signals into discrete digital representations.
Why This Document Matters
This lecture is essential for students seeking a deep understanding of data conversion techniques used in MEMS design. It’s particularly valuable for those planning to work with sensor signal processing, embedded systems, or mixed-signal integrated circuit design. Understanding ADCs is crucial for accurately capturing and interpreting data from MEMS devices. This material will be most helpful when you are studying signal conditioning, data acquisition systems, and the limitations of real-world measurement.
Topics Covered
* Track and Hold (T/H) circuits – fundamental operation and design considerations
* Various ADC architectures, including serial-slope and successive approximation types
* Flash ADC characteristics and potential error sources
* Detailed comparator design techniques for high-speed and accurate conversion
* Techniques for mitigating common ADC imperfections
* Switched-capacitor techniques for integrating T/H functions with other signal processing blocks
* Input common-mode cancellation strategies
What This Document Provides
* In-depth exploration of Track and Hold circuit variations, including differential implementations.
* Discussion of key performance parameters and trade-offs in ADC design.
* Analysis of error mechanisms within Flash ADCs, such as comparator offset and metastability.
* Examination of single-stage and cascaded amplifier configurations for comparator circuits.
* Insights into combining Track and Hold functionality with charge redistribution and difference amplifiers.
* Conceptual explanations supported by circuit diagrams and illustrative examples.
