F. Silveira

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A new design methodology based on a unified treatment of all the regions of operation of the MOS transistor is proposed. It is intended for the design of CMOS analog circuits and especially suited for low power circuits where the moderate inversion region often is used because it provides a good compromise between speed and power consumption. The synthesis(More)
A new class AB output stage is presented which extends a family of recently proposed stages based on current mirrors without requiring extra-compensation capacitances. In-depth circuit analysis also shows the significant advantage of such stages for low-power consumption and leads to the derivation of an optimum design strategy. Experimental realizations(More)
This paper demonstrates that fully-depleted (FD) silicon-on-insulator (SOI) technology offers unique opportunities in the ®eld of low-voltage, low-power CMOS circuits. Beside the well-known reduction of parasitic capacitances due to dielectric isolation, FD SOI MOSFETs indeed exhibit near-ideal body factor, subthreshold slope and current drive. These assets(More)
The design of a rail-to-rail micropower comparator in CMOS technology is described. The circuit is intended for implantable biomedical devices powered by batteries, with a total consumption of 500nA and operation up to supply voltages of 2V. This cell, currently being fabricated, has a core die area of 0.27 mm 2 on a 2.4###m standard analog CMOS technology(More)
BACKGROUND This study aimed to evaluate changes in the enamel surface of bovine teeth after whitening with exogenous bleaching agents: 10% carbamide peroxide (group 1), 16% carbamide peroxide (group 2) and 35% hydrogen peroxide activated by a light-emitting diode (LED) (group 3). The evaluations were performed by scanning electron microscopy (SEM). (More)
BACKGROUND Endodontic therapy is considered a series of important and interdependent steps, and failure of any of these steps may compromise the treatment outcome. This study aimed to evaluate the effectiveness of three different rotary systems in removing obturation materials during endodontic retreatment using scanning electron microscopy (SEM) analysis.(More)
BACKGROUND The aim of this study was to evaluate the fracture rates of ProTaper rotary files used in the endodontics extension clinic of the Undergraduate Dentistry Course of the Pontifical Catholic University of Minas Gerais during the prior eight years. MATERIAL AND METHODS Control record data regarding file usage by students were collected and analyzed(More)
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