A low-power silicon-on-insulator PWM discriminator for biomedical applications

• Autor(a) principal: Lima, Jader A. de [UNESP]
• Data de Publicação: 2000
• Outros Autores: Silva, Sidnei F. [UNESP], Cordeiro, Adriano S. [UNESP], Araujo, Alexandro C. [UNESP], Verleysen, Michel [UNESP]
• Tipo de documento: Artigo de conferência
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1109/ISCAS.2000.857418; http://hdl.handle.net/11449/130712
• topic: Digital filters; Electric network analysis; Electric network synthesis; Energy utilization; Image analysis; Image quality; Integrated circuit layout; Phase comparators; Pulse width modulation; Signal encoding; Silicon on insulator technology; Body-implanted neurostimulators; Fast-settling comparators; CMOS integrated circuits

A CMOS/SOI circuit to decode PWM signals is presented as part of a body-implanted neurostimulator for visual prosthesis. Since encoded data is the sole input to the circuit, the decoding technique is based on a double-integration concept and does not require dc filtering. Nonoverlapping control phases are internally derived from the incoming pulses and a fast-settling comparator ensures good discrimination accuracy in the megahertz range. The circuit was integrated on a 2 mu m single-metal SOI fabrication process and has an effective area of 2mm(2) Typically, the measured resolution of encoding parameter a was better than 10% at 6MHz and V-DD=3.3V. Stand-by consumption is around 340 mu W. Pulses with frequencies up to 15MHz and alpha = 10% can be discriminated for V-DD spanning from 2.3V to 3.3V. Such an excellent immunity to V-DD deviations meets a design specification with respect to inherent coupling losses on transmitting data and power by means of a transcutaneous link.