PVT compensated OTA design on SOI-CMOS nanometer technologies
In this study the design of a PVT compensated rail-to-rail input stage with constant transconductance and a high gain stage are presented, with the aim of providing a robust alternative to the problem of constant transconductance, reduced gain and at-band gain's variation of amplifiers in nanom...
| Autor: | |
|---|---|
| Tipo de recurso: | tesis de maestría |
| Estado: | Versión aceptada para publicación |
| Fecha de publicación: | 2012 |
| País: | México |
| Institución: | Instituto Nacional de Astrofísica, Óptica y Electrónica |
| Repositorio: | Repositorio Institucional del INAOE |
| Idioma: | inglés |
| OAI Identifier: | oai:inaoe.repositorioinstitucional.mx:1009/781 |
| Acceso en línea: | http://inaoe.repositorioinstitucional.mx/jspui/handle/1009/781 |
| Access Level: | acceso abierto |
| Palabra clave: | info:eu-repo/classification/Circuitos integrados analógicos CMOS/CMOS analogue integrated circuits info:eu-repo/classification/Circuitos de procesamiento analógico/Analogue processing circuits info:eu-repo/classification/Amplificadores/Amplifiers info:eu-repo/classification/Amplificadores diferenciales/Differential amplifiers info:eu-repo/classification/Amplificadores operacionales/Operational amplifiers info:eu-repo/classification/cti/1 info:eu-repo/classification/cti/22 info:eu-repo/classification/cti/2203 |
| Sumario: | In this study the design of a PVT compensated rail-to-rail input stage with constant transconductance and a high gain stage are presented, with the aim of providing a robust alternative to the problem of constant transconductance, reduced gain and at-band gain's variation of amplifiers in nanometer technologies. Initially, an overview about the main concerns to downscaling in transistor sizing and some characteristics and details about SOI nanometer technology are given in order to identify the advantages and drawbacks with respect to CMOS technology. Subsequently, a solution to the sizing problem in current technology is adopted, which make the design of circuits possible. A rail-to-rail input stage with constant transconductance is designed, whose outstanding characteristics are the high robustness to PVT variations and the easy integration with other stages. These characteristics are obtained using the Feedback Differential Pair (FDP) circuit, improving the biasing, sub-threshold region for input differential pairs and an addition current circuit with opposite behavior in temperature with respect to the input signal section. For the gain stage design, first the problem of at-band gain's variation had to be solved. Then, some topologies to obtain high gain are reviewed, and at the same time some design considerations are reviewed and proposed in order to identify robust topologies. Applying these considerations and the transconductance addition technique, a two stage amplifier with two transconductance additions is proposed, which reaches a high gain value without using cascode structures or boosting techniques. Finally, the two designed circuits are integrated as an OTA circuit, which is fully characterized including PVT and Monte Carlo simulations in order to verify that all the design considerations were correct. |
|---|