In this thesis, a novel Direct-Charge-Transfer (DCT) integrator structure is proposed, which can settle much faster than regular switch-capacitor integrators. A new Spread-Spectrum Dynamic Element Matching (SS-DEM) algorithm is also introduced, which can effectively spread or shape the nonlinearity error of multi-bit DAC in the feedback path, thus improve the...
Multi-stage delta-sigma (ΔΣ) architectures, commonly known as MASH, are the preferred choice for analog-to-digital converters (ADCs) used in broadband communication applications, where high-resolution (above 14 bits) and high-bandwidth (several MHz) performances are required. Current state-of-the-art designs are capable of as much as 5-MS/s output data rates with 90-dB SNR. However,...
The exponential rate of advances in modern communication devices in the last several years have brought us higher levels of functionality and performance as well as reductions in physical size and power consumption. To continue this rate of advancement, next generation systems require wider bandwidth and higher resolution ADCs. Additionally,...
Enabled by continued device scaling in CMOS technology, more and more functions that were previously realized in separate chips are getting integrated on a single chip nowadays. Integration on silicon has opened the door to new portable wireless applications, and initiated a widespread use of these devices in our common...
Recently, delta-sigma modulation has become a widely applied technique for high-performance analog-to-digital conversion of narrow-band signals. Most of the early designs used discrete-time structure for good accuracy and good linearity. The transfer functions are independent of the clock frequency. However, high unity-gain bandwidths of the opamps are required to satisfy...
Analog-to-Digital Data Converters (ADCs) used in instrumentation and measurements often require high absolute accuracy, including excellent linearity and negligible dc offset. Incremental data converters (IDCs) provide a solution for such measurement applications. Since IDCs are essentially delta-sigma converters with reset operation before each conversion, they retain most of the advantages...
With the growing demand for portable/consumer electronics, such as digital
audio/video (AV), the downscaling of device dimensions, which enables the
integration of an increasing number of transistors in a single chip, is mandatory.
This trend also continuously pushes the power supply voltage down to reduce the
power consumption and improve...
The demand for portable electronic systems and the continued
down-scaling of device dimensions resulted in rapid improvement in
the performance of integrated systems. Several low-voltage design
techniques have been proposed to operate analog circuits with sub-1V
supply. However, these techniques require higher power consumption
to achieve large dynamic range while...
With the ever-increasing demand for portable devices used in applications
such as wireless communication, mobile computing, consumer electronics, etc.,
the scaling of the CMOS process to deep submicron dimensions becomes more
important to achieve low-cost, low-power and high-performance digital systems.
However, this downscaling also requires similar shrinking of the supply...