An 8-Bit Analog-to-Digital Converter for Battery Operated Wireless Sensor Nodes

<p>Wireless sensing networks (WSNs) collect analog information transduced into the form of a voltage or current. This data is typically converted into a digital representation of the value and transmitted wirelessly using various modulation techniques. As the available power and size is limited for wireless sensor nodes in many applications, a medium resolution Analog-to-Digital Converter (ADC) is proposed to convert a sensed voltage with moderate speeds to lower power consumption. Specifications also include a rail-to-rail input range and minimized errors associated with offset, gain, differential nonlinearity, and integral nonlinearity. To achieve these specifications, an 8-bit successive approximation register ADC is developed which has a conversion time of nine clock cycles. This ADC features a charge scaling array included to achieve minimized power consumption and area by reducing unit capacitance in the digital-to-analog converter. Furthermore, a latched comparator provides fast decisions utilizing positive feedback. The ADC was designed and simulated using Cadence Virtuoso with parasitic extraction over expected operating temperature range of 0 – 85°C. The design was fabricated using TSMC’s 65 nanometer RF GP process and tested on a printed circuit board to verify design specifications. The measured results for the device show an offset and gain error of +7 LSB and 31.1 LSB, respectively, and a DNL range of -0.9 LSB to +0.8 LSB and an INL range of approximately -4.6 LSB to +12 LSB. The INL is much improved in regard to the application of the temperature sensor. The INL for this region of interest is from -3.5 LSB to +2.8 LSB.</p>

Name thesis:degree_name

Master of Science in Electrical Engineering (MSEE)

Level thesis:degree_level

Thesis

Year dc:date.available

2021

Author dc:creator

• Suggs, Marvin Wayne, Jr.

Advisor dc:contributor.advisor

• Mantooth, H. Alan

Contributors dc:contributor

• Chen, Zhong
• Dix, Jeff

• ADC
• Digital Signals
• Machine Learning Algorithms
• Remote Monitoring
• SAR
• Temperature Sensor Data
• Wireless Sensor Node
• Electrical and Electronics
• Power and Energy
• Signal Processing

Repository record dc:identifier

https://scholarworks.uark.edu/etd/4046

OAI identifier oai:identifier

oai:scholarworks.uark.edu:etd-5596