J.L. Freitas Vieira, Mhrcio A. CO and Lucian0 D. Zorzal Universidade Federal do Espirito Santo Departamento de Engenharia Eldtrica LEPAC PO Box: 0 1-90 1 1 Vit6ria ES Brazil 29060-970 Fax: 55.27.335.2650 ABSTRACT A new low cost high power factor electronic ballast is introduced in this paper. The proposed topology is based on a single power processing stage to provide high frequency voltage to ...

 Traditional 2-level high-frequency pulse width modulation (PWM) inverters for motor drives have several problems associated with their high frequency switching which produces common-mode voltage and high voltage change (dV/dt) rates to the motor windings. Multilevel inverters solve these problems because their devices can switch at a much lower frequency. Two different multilevel topologies a...

One of the difficulties with PWM switching converters is high switching loss and electromagnetic interference due to switching at non-zero voltage and current, which limits the operating frequency. In order to reduce the converter volume and weight (by increasing the frequency) and reducing switching losses, zero voltage and current switching methods are recommended. In this paper, four main ze...

One of the difficulties with PWM switching converters is high switching loss and electromagnetic interference due to switching at non-zero voltage and current, which limits the operating frequency. In order to reduce the converter volume and weight (by increasing the frequency) and reducing switching losses, zero voltage and current switching methods are recommended. In this paper, four main ze...

This article shows the proposal of a linear–assisted converter or linear–&–switching hybrid converter with a constant switching frequency for photovoltaic solar DC-DC regulators. The control loop of the system is based on the current–mode technique. The main disadvantage of a converter with current– mode control is the inherent instability of the loop when switch duty ratios are greater than 0....

Switched-capacitor DC-DC converters are useful alternatives to inductor-based converters in many lowpower and medium-power applications. This work develops a straightforward analysis method to determine a switched-capacitor converter’s output impedance (a measure of performance and power loss). This resistive impedance is a function of frequency and has two asymptotic limits, one corresponding ...

In this paper we introduce a CMOS low voltage/low power (LV/LP) voltage controlled oscillator (VCO). It includes a simple V-I converter, a current controlled ring oscillator based on new differential delay cells, and a source-coupled differential pair to convert differential signal to single-ended signal. The V-I converter is implemented as a source follower type, exhibiting excellent linearity...

A novel digitally programmable floating impedance converter circuit is realized using two CMOS digitally programmable differential voltage current conveyors and three grounded passive elements. The realized impedance converter can provide digitally programmable floating impedances like ideal floating resistor, capacitor, inductor and frequency dependent negative resistor through appropriate sel...

This paper presents a high reliability and high efficiency light-emitting diodes for low power application. An AC-DC converter is a common converter topology approach for low voltage application. The prefect option for this approach is a Asymmetrical Half Bridge converter it has high efficiency constant switching frequency operation and small output filter. Asymmetrical Half Bridge is a perfect...

This article describes a single-input dual output (SIDO) linear-assisted DC/DC converter. Linear-assisted DC/DC converters are structures that allow to take advantages of the two classic alternatives in the design of power supply systems: voltage linear regulators and switching DC/DC converters. Thanks to the combination of a switching converter and two voltage linear regulators, the proposed S...