• Journal of Power Electronics
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• v.15 no.6
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• pp.1673-1681
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• 2015

A low dropout (LDO) regulator with a wide-bandwidth is proposed in this paper. The regulator features a Human Body Model (HBM) 8kV-class high robustness ElectroStatic Discharge (ESD) protection circuit, and two error amplifiers (one with low gain and wide bandwidth, and the other with high gain and narrow bandwidth). The dual error amplifiers are located within the feedback loop of the LDO regulator, and they selectively amplify the signal according to its ripples. The proposed LDO regulator is more efficient in its regulation process because of its selective amplification according to frequency and bandwidth. Furthermore, the proposed regulator has the same gain as a conventional LDO at 62 dB with a 130 kHz-wide bandwidth, which is approximately 3.5 times that of a conventional LDO. The proposed device presents a fast response with improved load and line regulation characteristics. In addition, to prevent an increase in the area of the circuit, a body-driven fabrication technique was used for the error amplifier and the pass transistor. The proposed LDO regulator has an input voltage range of 2.5 V to 4.5 V, and it provides a load current of 100 mA in an output voltage range of 1.2 V to 4.1 V. In addition, to prevent damage in the Integrated Circuit (IC) as a result of static electricity, the reliability of IC was improved by embedding a self-produced 8 kV-class (Chip level) ESD protection circuit of a P-substrate-Triggered Silicon Controlled Rectifier (PTSCR) type with high robustness characteristics.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.11 no.2
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• pp.13-26
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• 2007

Background: Neurofeedback is an electroencephalographic biofeedback technique for training individuals to alter their brain activity via operant conditioning. Also neurofeedback is a form of behavioural training aimed at developing skills for brain activity. Within the past decade, several neurofeedback studies have been published that tend to overcome the methodological shortcomings of earlier studies. This research describes the methodical basis of neurofeedback and reviews the evidence base for its clinical efficacy and effectiveness in attention-deficit hyperactivity disorder (ADHD). Methods: In neurofeedback training, self-regulation of specific aspects of electrical brain activity is acquired by means of immediate feedback and positive reinforcement. In frequency training, activity in different EEG frequency bands has to be decreased or increased. Slow cortical potentials (SCPs) training is focused on the regulation of cortical excitability. Results: Neurofeedback studies revealed training-specific effects on, for example, attention and memory processes and performance improvements in real-life conditions, in healthy subjects as well as in patients. In several studies it was shown that ADHD symptomatology was reduced after frequency training or SCP(Slow cortical potentials) training. Moreover a decrease of impulsivity errors and an increase of the contingent negative variation. Conclusions: This research provides evidence for both positive behavioural and specific neurophysiological effects of neurofeedback training. Also there is growing evidence for neurofeedback as a valuable module in neuropsychiatric disorders. Further, controlled studies are warranted.