CMOS-based active pixel for low-light-level detection: Analysis and measurements

An analysis of the active pixel sensor (APS), considering the doping profiles of the photodiode in an APS fabricated in a 0.18 μm standard CMOS technology, is presented. A simple and accurate model for the junction capacitance of the photodiode is proposed. An analytic expression for the output voltage of the APS obtained with this capacitance model is in good agreement with measurements and is more accurate than the models used previously. A different mode of operation for the APS based on the dc level of the output is suggested. This new mode has better low-light-level sensitivity than the conventional APS operating mode, and it has a slower temporal response to the change of the incident light power. At 1μW/cm2 and lower levels of light, the measured signal-to-noise ratio (SNR) of this new mode is more than 10 dB higher than the SNR of previously reported APS circuits. Also, with an output SNR of about 10 dB, the proposed dc level is capable of detecting light powers as low as 20 nW/cm2, which is about 30 times lower than the light power detected in recent reports by other groups. © 2007 IEEE.

Latin America and the Caribbean in the World Economy 2004: 2005 trends

Includes bibliography

Latin America and the Caribbean in the World Economy 2005-2006

Includes bibliography

Latin America and the Caribbean in the World Economy 2010-2011: The region in the decade of the emerging economies

Incluye Bibliografía

Review of Caribbean economic and social performance in the 1980's and 1990's

Includes bibliography

The Latin American Pacific Basin initiative and the Asia-Pacific region

Includes bibliography

Opportunities for trade and investment between Latin America and Asia-Pacific: the link with APEC

Includes bibliography

Opportunities for convergence and regional cooperation: Unity Summit of Latin America and the Caribbean

Includes Bibliography

Trade and the environment in the context of the World Trade Organization

Includes bibliography

La dimensión del desarrollo en la política de competencia

Incluye Bibliografía

Asimetrías, comercio y financiamiento en el Area de Libre Comercio de las Américas (ALCA), y en América Latina y el Caribe

Incluye Bibliografía

Intervenções educativas com usuários de medicamentos como estratégias terapêuticas

A review and analysis of the literature on educative interventions (EI) for medicine users was carried out. For this purpose, databases were searched by employing descriptors related to pharmaceutical care, education and health, covering the period from 1997 to early 2011. A set of 21 articles related to EI with medicine users were selected, 18 (85.7%) of which referred to studies on basic health care. The EI most commonly reported in the articles were: talks, group discussions and educative material. The positive outcomes reported were: improvement in quality of life (better acceptance of the disease), economic advantages (reduction in number of medical consultations) and clinical improvement (risk reduction, prevention of complications).

A saúde e seu direito no olhar do usuário sob a luz da constituição de 1988

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Processos de criação em sala de aula: experiências fenomenológicas como formas de reaprender a ver o mundo

Pós-graduação em Artes - IA

Televisão e saúde: a obesidade em discussão

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)