In this paper, we present a highly efficient and compact voltage doubler based on a resonant S'\\itched-capacitor converter implemented with GaN FF.Ts. Two possible approad1es for its implementation are analy:red and compared. In the first approach, the resonant inductor is placed in series with a resonant capacitor, conducting a sinusoidal current, while in the second, it is placed in series with the input source, conducting rectified sinusoidal current Roth resonant converters have the same voltage gain, and although the change in the position of the resonant inductor is, at the first glance, of minor importance, the analysis and results show that it has huge impact on the capability to achieve zero-voltage switching (ZVS) transitions at low output power. The experimental results dearly show that at low loads when the resonant inductor is in series with the resonant capacitor, the S'\\itching frequency can be significantly higher than the resonant frequency and that it is, practically, impossible to achieve ZVS transitions, forcing the implementation of cycle skipping. The prototype implemented for the experiments can provide up to 4.5-kW losing between 20 and 22 W. In the case of tight load (500 W), the power losses were only 2-3 W. Its power density ls higher than 6S kW/dm 3 . The same resonant converter was tested '\\ith Si CoolMOS devices as well and the impact of the semiconductor tedmology on the overall power losses was verified. Due to higher Coss capacitance, the Si-based converter has 40% higher power losses at full power than its GaN-based counterpart. The components of the GaN-based converter occupy only 65 cm 3 , which opens a possibility to obtain a design '\\ith extremely high power density.
Index Ten11s-Resonant converters, switched capacitors, zero voltage S'\\itching (ZVS ).
In this paper flexible printed electrodes applicable to wearable electronics are presented. Using innovative materials as Laser Induced Graphene (LIG) and printed electronics, three type of electrodes based in LIG, silver chloride and carbon inks have been compared during the acquisition of bipotentials as electrocardiogram, electromyogram and electrooculogram. For this last one, a completely new framework for acquisition have been developed. This framework is based in a printed patch which integers 6 electrodes for the EOG acquisitions and an ad-hoc signal processing to detect the direction and amplitude of the eye movement. The performance of the developed electrodes have been compared with commercial ones using the characteristics parameters of each signal as comparative variables. The results obtained for the flexible electrodes have shown a similar performance than the commercial electrodes with an improvement in the comfort of the user.
Wearable monitoring devices are now a usual commodity in the market, especially for the monitoring of sports and physical activity. However, specialized wearable devices remain an open field for high-risk professionals, such as military personnel, fire and rescue, law enforcement, etc. In this work, a prototype wearable instrument, based on reconfigurable technologies and capable of monitoring electrocardiogram, oxygen saturation, and motion, is presented. This reconfigurable device allows a wide range of applications in conjunction with mobile devices. As a proof-of-concept, the reconfigurable instrument was been integrated into ad hoc glasses, in order to illustrate the non-invasive monitoring of the user. The performance of the presented prototype was validated against a commercial pulse oximeter, while several alternatives for QRS-complex detection were tested. For this type of scenario, clustering-based classification was found to be a very robust option.
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