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dc.contributor.advisor Brooke, Martin en_US
dc.contributor.author Aleksanyan, Arnak en_US
dc.date.accessioned 2011-06-09T13:00:15Z
dc.date.available 2013-05-28T04:30:06Z
dc.date.issued 2011 en_US
dc.identifier.uri http://hdl.handle.net/10161/3956
dc.description Dissertation en_US
dc.description.abstract <p>Many medical, environmental, and industrial control applications rely on wide-dynamic-range sensors and A/D converter systems. For most photo-detector-based applications, the input-current is integrated onto a capacitor, either with a variable time, or a variable capacitor value, followed by a sample-and-hold and a voltage A/D converter. The penalty for achieving wide-dynamic-range with the above approach is power and circuit complexity. </p><p>We propose to use the unique properties of current-input continuous-time Delta-Sigma A/D converters to combine the photo-detector current-integration with simultaneous wide-dynamic-range A/D conversion, using programmable reference currents and programmable clock frequencies. </p><p>A programmable current-input wide-dynamic-range Delta-Sigma A/D converter is designed and fabricated using MOSIS AMI 1.5 um 5 V CMOS process. The programmable A/D converter test results exhibit a consistent 12-bit resolution over the programmability range of the reference-currents, from 17.2 nA to 4.4 uA. The supply-current varies from 60 uA to 240 uA, whereas the A/D converter sample-rates increase from 4 Samples/s to 1 kSamples/s, achieving an overall system-dynamic-range of 20-bits. </p><p>An RF-powered version is designed and fabricated using MOSIS ON 0.5 um 3 V CMOS process. It is designed to work at 128 Samples/s to 11.25 kSamples/s sample-rates, achieving 12-bit resolution with only 128 oversampling ratio. The A/D converter supply-current is designed to range from 10 uA to 70 uA to allow its integration with an RF-power source. The RF-powered version of the programmable Delta-Sigma A/D converter includes an on-chip voltage regulator that generates a stable 3 V DC-voltage, and consumes only 15 uA current.</p> en_US
dc.subject Electrical Engineering en_US
dc.subject delta-sigma adc en_US
dc.subject low power sensor en_US
dc.subject programmable adc en_US
dc.subject rfid en_US
dc.title Wide-Dynamic-Range Continuous-Time Delta-Sigma A/D Converter for Low-Power Energy Scavenging Applications en_US
dc.type Dissertation en_US
dc.department Electrical and Computer Engineering en_US
duke.embargo.months 24 en_US

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