The CD4046BC micropower phase-locked loop (PLL) consists of a low power, linear, voltage-controlled oscillator (VCO), a source follower, a zener diode, and two phase comparators. The two phase comparators have a common signal input and a common comparator input. The signal input can be directly coupled for a large voltage signal, or capacitively coupled to the self-biasing amplifier at the sign...

One of the most important Fuel cells (FCs) is Proton Exchange Membrane Fuel Cells (PEMFCs). The outputvoltage of this FC depends on current loads. This paper tries to introduce, implement and control the voltage ofPEMFC, during load variations. The output voltage of fuel cell should be constant during load variation. Toachieve this goal, a controller should be designed. Here, the Lead-Lag contr...

Step-up dc-dc converters have to cope with extremely low input voltages when used in combination with energy harvesting sources like thermogenerators, inductive generators or solar cells. The presented dc-dc converter is characterized by a high efficiency, up to 70 % in the input voltage range between 200 mV and 500 mV, and a minimum start-up voltage of 70 mV. It can deliver an output power of ...

By using a quadratic compensation slope, a CMOS current-mode buck DC-DC converter with constant frequency characteristics over wide input and output voltage ranges has been developed. The use of a quadratic slope instead of a conventional linear slope makes both the damping factor in the transfer function and the frequency bandwidth of the current feedback loop independent of the converter’s ou...

Received Feb 3, 2017 Revised Mar 18, 2017 Accepted May 5, 2017 Dual input dc-dc converters have two input voltage sources or one input source and an energy storage system like ultra capacitor, PV, battery, super capacitors and a single output load. In order to process the power in hybrid energy systems using reduced part count, researchers have proposed several multi-input dc-dc power converter...

A Double input DC to DC converter for low voltage energy sources applications is proposed in this paper. The proposed converter is buck-boost converter which can step up or step down the input voltage according to output voltage required at load end. The converter is able to boost up voltage of energy sources such as solar photovoltaic and wind energy system of relatively low voltage. The conve...

This paper presents a method for the design of shell-type, single-phase distribution transformers to obtain the manufacturing specifications. The method is simple, efficient and accurate. By an exhaustive analysis, it is concluded that the obtained solution is the global optimum. The following constraints are imposed: excitation current, no-load losses, total losses, impedance and efficiency. T...

Digital sub-threshold circuits are significant for ultra-low power (ULP) applications. Operating circuits at ultra-low voltage levels leads to the less power per operation. An optimized method is separating the logic blocks based on performance requirement and utilizing multiple-supply voltage (VDD) for each blocks. In order to prevent an enormous static current in these multi-VDD circuits, vol...

New design and optimization of charge pump rectifiers using diode-connected MOS transistors is presented in this paper. An analysis of the output voltage and Power Conversion Efficiency (PCE) is given to guide and evaluate the new design. A novel diode-connected MOS transistor for UHF rectifiers is presented and optimized, and a high efficiency N-stage charge pump rectifier based on this new di...

in this work, we developed a method which combined the processes of acid-leaching, ammonium jarosite precipitating and electro-depositing to recover copper and nickel from electroplating sludge. residual sludge from an electroplating plant located in qingdao was used for acid-leaching, and more than 95% of copper, nickel, zinc, chromium and iron were extracted from the sludge. after acid-leachi...