Dynamic Element Matching Techniques For Delta-Sigma ADCs With Large Internal Quantizers

<p>This thesis presents two methods that enable high internal quantizer resolution in delta-sigma analog-to-digital converters. Increasing the quantizer resolution in a delta-sigma modulator can increase SNR, improve stability and reduce integrator power consumption. However, each added bit of quantizer resolution also causes an exponential increase in the power dissipation, required area and complexity of the dynamic element matching (DEM) circuit required to attenuate digital-to-analog converter (DAC) mismatch errors. One way to overcome these drawbacks is to segment the feedback signal, creating a "coarse" signal and a "fine" signal. This reduces the DEM circuit complexity, power dissipation, and size. However, it also creates additional problems. The negative consequences of segmentation are presented, along with two potential solutions: one that uses calibration to cancel mismatch between the "coarse" DAC and the "fine" DAC, and another that frequency-shapes this mismatch error. Mathematical analysis and behavioral simulation results are presented. A potential circuit design for the frequency-shaping method is presented in detail. Circuit simulations for one of the proposed implementations show that the delay through the digital path is under 7 ns, thus permitting a 50 MHz clock frequency for the overall ADC.</p>

Name thesis:degree_name

MS

Grantor dc:publisher

Brigham Young University - Provo

Author dc:creator

• Nordick, Brent C.

• delta-sigma
• delta
• sigma
• dynamic element matching
• DEM
• ADC
• analog to digital converter
• large internal quantization
• requantization
• calibration
• Electrical and Computer Engineering

Language dc:language

English

Repository record dc:identifier

https://scholarsarchive.byu.edu/etd/134

OAI identifier oai:identifier

oai:scholarsarchive.byu.edu:etd-1133