High Performance Class-AB Output Stage Operational Amplifiers for Continuous-time Sigma-delta ADC
| dc.contributor | Silva-Martinez, Jose | |
| dc.creator | Krishnan, Lakshminarasimhan | |
| dc.date.accessioned | 2012-10-19T15:28:56Z | |
| dc.date.accessioned | 2012-10-22T17:58:34Z | |
| dc.date.accessioned | 2017-04-07T20:00:31Z | |
| dc.date.available | 2012-10-19T15:28:56Z | |
| dc.date.available | 2012-10-22T17:58:34Z | |
| dc.date.available | 2017-04-07T20:00:31Z | |
| dc.date.created | 2011-08 | |
| dc.date.issued | 2012-10-19 | |
| dc.description.abstract | One of the most critical blocks in a wide-band continuous time sigma delta (CTSD) analog-to-digital converter (ADC) is the loop filter. For most loop filter topologies, the performance of the filter depends largely on the performance of the operational amplifiers (op-amps) used in the filter. The op-amps need to have high linearity, low noise and large gain over a wide bandwidth. In this work, the impact of op-amp parameters like noise and linearity on system level performance of the CTSD ADC is studied, and the design specifications are derived for the op-amps. A new class-AB bias scheme, which is more robust to process variations and has an improved high frequency response over the conventional Monticelli bias scheme, is proposed. A biquadratic filter which forms the input stage of a 5th order low pass CTSD ADC is used as a test bench to characterize the op-amp performance. The proposed class-AB output stage is compared with the class-AB output stage with Monticelli bias scheme and a class-A output stage with bias current reuse. The filter using the new op-amp architecture has lower power consumption than the other two architectures. The proposed class AB bias scheme has better process variation and mismatch tolerance compared to the op-amp that uses conventional bias scheme. | |
| dc.identifier.uri | http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-9896 | |
| dc.language.iso | en_US | |
| dc.subject | class-AB | |
| dc.subject | output stage | |
| dc.subject | high performance op-amp | |
| dc.subject | operational amplifier | |
| dc.title | High Performance Class-AB Output Stage Operational Amplifiers for Continuous-time Sigma-delta ADC | |
| dc.type | Thesis |