Voltage regulator

About: Voltage regulator is a research topic. Over the lifetime, 33536 publications have been published within this topic receiving 350859 citations.

Method of retaining memory state in a programmable conductor RAM

Abstract: A non-volatile memory device, such as a Programmable Conductor Random Access Memory (PCRAM) device, having an exemplary memory stored state retention characteristic is disclosed. There is provided a method for retaining stored states in a random access memory device generally comprising the steps of programming a memory cell or an array of memory cells by applying a first voltage to the cells and stabilizing the cells by applying a second voltage to the cells, which is less than the first voltage. The second voltage, which acts as a stabilizing voltage, may be a read-out voltage. The second voltage may also be continuously applied to the cells. The second voltage may also be provided as a sweep voltage, a pulse voltage, or a step voltage.

PMOS low dropout voltage regulator using non-inverting variable gain stage

Abstract: PROBLEM TO BE SOLVED: To improve the stability and PSRR characteristic of an internal compensating type PMOS low dropout voltage regulator. SOLUTION: A non-inverting variable gain amplifier stage 202 is used for this voltage regulator 200. The gain of the non-inverting variable gain amplifier stage is regulated according to the load current carried in a power PMOS device 206 so as to increase the gain according to the reduction in load current, and the second pole of the voltage regulator 200 is pushed up to the unit gain frequency or more of the voltage regulator. The gain of the non-inverting variable gain amplifier 202 is regulated according to the load current carried in the power PMOS device 206 so as to reduce the gain according to the increase in load current, and the unit gain band width of a loop formed in a compensating capacitor 208 is substantially kept constant.

Automotive alternator and solid state regulator tester

Abstract: A tester for a solid state voltage regulator includes two parallel branches available for interconnection to the two output contacts of the voltage regulator. The two branches both interconnect to the high voltage side of a battery. One of the branches includes a resistor in parallel combination with an indicator bulb. One of the branches includes a normally open switch. For use with automobile alternators having a built-in regulator, the tester can be connected directly to the regulator and test both the regulator and the alternator. When the regulator is independent of the alternator, it can be tested by itself by using actual rotor current available from an alternator used in conjunction with the tester. The on/off condition of the indicator bulb, when the switch and various contact terminals are interconnected, provides an indication of the effective operation of the regulator. A volt meter can be included integrally with the tester to provide output readings of the regulator.

A Novel Transformer-less Adaptable Voltage Quadrupler DC Converter with Low Switch Voltage Stress

Abstract: In this paper, a novel transformer-less adjustable voltage quadrupler dc-dc converter with high-voltage transfer gain and reduced semiconductor voltage stress is proposed. The proposed topology utilizes input-parallel output-series configuration for providing a much higher voltage gain without adopting an extreme large duty cycle. The proposed converter cannot only achieve high step-up voltage gain with reduced component count but also reduce the voltage stress of both active switches and diodes. This will allow one to choose lower voltage rating MOSFETs and diodes to reduce both switching and conduction losses. In addition, due to the charge balance of the blocking capacitor, the converter features automatic uniform current sharing characteristic of the two interleaved phases for voltage boosting mode without adding extra circuitry or complex control methods. The operation principle and steady analysis as well as a comparison with other recent existing high step-up topologies are presented. Finally, some simulation and experimental results are also presented to demonstrate the effectiveness of the proposed converter.

DC voltage control and stability analysis of PWM-voltage-type reversible rectifiers

Abstract: A PWM voltage rectifier has useful characteristics on its DC and AC sides. On its DC side, a DC-link unidirectional voltage is obtained and bidirectional power transfer capability is possible by reversing the flow direction of the DC-link current. On its AC side, near sinusoidal current waveforms and AC four-quadrant operation can be obtained, leading to high-quality power being exchanged between the power converter and the mains. The use of AC filters becomes unnecessary. The rectifier DC voltage must be regulated to a constant value. In this paper, three solutions for the DC voltage control are presented. In the first solution, the DC voltage is controlled by acting upon the quadrature component of the power converter fundamental Park's voltages with relation to the mains voltages. Slow responses are necessary because of stability reasons. Also, load power variations produce both active and reactive power variations in the power converter AC side. To improve the DC voltage response, a second control solution is presented. The power converter currents in Park's coordinates must be controlled. The DC voltage is controlled by controlling the direct Park's current component and, thus, acting only on the active power of the converter AC side. Faster responses are achieved. In this case, load power variations do not produce reactive power variations in the converter AC side. The third control solution is a simplified version of this last one. Experimental results from a 2 kVA IGBT-based prototype showing good system dynamic performance are presented.