This thesis describes circuit architectures and techniques that facilitate the
automatic synthesis and fabrication of analog-to-digital converters (ADCs). Since
automated synthesis already exists for digital circuits and is part of the digital
circuit design flow, this work demonstrates the feasibility of ADC synthesis with
little or no modification to presently...
Advances in process technologies have led to the development of low-power high speed digital signal processing blocks that occupy small areas. These advances are critical in the development of portable electronic devices with small feature size and long battery life. However, the design of analog and mixed-signal
building blocks, especially...
Delta-sigma analog-to-digital converters (ADCs) are suitable for many applications due to several advantages such as relaxed anti-aliasing filter, high signal-to noise and distortion ratio (SNDR) and most important of all, reduced sensitivity to
analog imperfections.This thesis introduces several structures to overcome loop imperfections and stability issues in delta-sigma modulators. First,...
Advances in electronic systems have lead to the demand for high resolution, high bandwidth Analog-to-Digital Converters (ADCs). Oversampled ADCs are well- known for high accuracy applications since they benefit from noise shaping and they usually do not need highly accurate components. However, as a consequence of oversampling, they have limited...
Hand-held devices are among the most successful consumer electronics in modern society. Behind these successful devices, lies a key analog design technique that involves high-performance analog-to-digital conversion combined with very low power consumption. This dissertation presents two different approaches to achieving high power efficiency from a two-step pipelined architecture, which...
A comprehensive and scalable solution for high-performance switched capacitor amplification is presented. Central to this discussion is the concept of ring amplification. A ring amplifier is a small modular amplifier derived from a ring oscillator that naturally embodies all the essential elements of scalability. It can amplify with accurate rail-to-rail...
In an industrial and consumer electronic marketplace that is increasingly demanding greater real-world interactivity in portable and distributed devices, analog to digital converter efficiency and performance is being carefully examined. The successive approximation (SAR) analog to digital converter (ADC) architecture has become popular for its high efficiency at mid-speed and...
As advanced wired and wireless communication systems attempt to achieve higher performance, the demand for high resolution and wide signal bandwidth in their associated ADCs is strongly increased. Recently, time-domain quantization has drawn attention from its scalability in deep submicron CMOS processes. Furthermore, there are several interesting aspects of time-domain...
Modern day CMOS processes are characterized by voltage scaling and geometry scaling. Geometry scaling helps reduce gate delays, thereby aiding in the design of data converters which use time based processing. Another artifact of geometry scaling is the increase in complexity of digital circuitry available on traditional analog ICs, as...
Data converters are ubiquitous building blocks of a signal chain. The rapid increase in
communication and connectivity devices presents new avenues for pushing the state of
the art analog to digital converters. Techniques for improving resolution, bandwidth,
linearity and bit-error rate, while reducing the power, energy and area is the...
Time-domain data conversion has recently drawn increased research attention for its highly digital nature in favor of process technology scaling. Also, as the time information being carried by binary voltage, time-domain operation is much less sensitive to voltage noise compared to conventional voltage domain operation. However, for analog-to-digital converter (ADC)...
Recent publications show that successive approximation register (SAR) analog to digital converters (ADC) are capable of achieving high efficiency over other ADC topologies. Furthermore, techniques have been adopted to process signals with low activity periods, such as biomedical and industrial sensors. Prior work used least- significant bit first quantization (LSBFQ)...
New amplifier architectures are presented using non-traditional methods of biasing. Time-based dynamic biasing and signal-based dynamic biasing are discussed in the context of new architectures. This includes a new form of ring amplification with a dynamic deadzone, allowing for a structure whose coarse path does not consume static power.
A procedure for automating the design and layout of analog-to-digital converters (ADCs) is presented. This procedure makes use of the existing synthesis and place-and-route tools that are common in digital circuit design. A method for adding rudimentary analog cells to the standard library is described, allowing the designer to synthesize...
Analog to digital converters (ADCs) are a critical part of communication between the physical world and the increasingly digital systems humans use every day. ADCs have inherent non-idealities that degrade performance. Nonlinearity is one of the most prevalent non-idealities that designers face. While calibration methods for nonlinearity exist in the...
This dissertation presents a phase domain in-loop-bandwidth spread-spectrum clock generation technique. In this proposed technique, a charge-based discrete-time loop filter is proposed to enable the phase domain in-loop-bandwidth spread-spectrum modulation without a delta-sigma modulator or time-to-digital converter. The in-loop-bandwidth modulation technique maximizes the loop bandwidth to improve phase noise suppression...
As the CMOS process scales down to submicron, digital circuit performance improves, while reduced supply voltage and lower transistor intrinsic gain make it difficult to implement analog circuits in a power efficient manner. Therefore, it has become advantageous to shift more analog signal processing functions conventionally realized in voltage (analog)...
The internet-of-things is a growing market segment which is based on an arrayof portable communication devices with high power efficiency. Advanced semiconductortechnology can easily improve their digital performance, but the samecannot be said for the analog blocks which are vital to their operation. Highperformance analog circuits continue to use conventional...
Demands of today's integrated society dependent on communication systems have driven the creation of ever more efficient analog-to-digital converters. For the same reasons, digital circuitry has rapidly expanded to serve all the different systems and needs of consumers. The trend of technology development has been to make these digital circuits...
Ring amplification has emerged as an efficient technique to drive large capacitive loads in switched capacitor circuits. We propose circuit techniques to demonstrate the first application of a ring amplifier in a non-capacitive feedback system of a LDO. These techniques enable a simple cap-less LDO structure in 180nm CMOS that...
In recent years, SAR ADCs have been shown to acheive faster conversion times and improved power efficiencies due to their simple building blocks that are digital in nature and scale favorably with technology. High resolution ADCs with stringent noise requirement has led to the adoption of hybrid ADC architectures such...
Successive-approximation-register (SAR) analog-to-digital converters are popular for medium accuracy, medium speed and low power applications, such as in biomedical applications. They have low latency and simple architecture compared with ΔΣ ADCs. This is because of SAR ADCs’ binary searching scheme. Furthermore, SAR ADCs can apply oversampling and noise shaping schemes...