Switch-mode power supplies usually emit electromagnetic interferences at the switching frequency and its harmonics. Inducing chaos in these systems has recently been suggested as a means of reducing these spectral emissions, yet at the expense of aggravating the overall magnitude of the ripple in the output voltage. We propose here a new nonlinear feedback control method, which induces chaos, a...

High power LED converter combined with switching power supply and current adjustment device for is presented. The switching power supply provides one stabilized voltage source, and the current adjustment device controls the output currents with a desired constant current and the over-load protection. The experiment results shows the circuit can work well and pass the load test and the electroma...

This paper describes some work in progress aimed at developing an expert system for fault diagnosis on switching mode power supplies. The system being developed is designed to interface with some existing automatic test equipment. Results of tests from this test equipment are the main input to the expert system. Another input is information about signals at various points in the circuit under t...

PSPICE modeling of a commercial LED driver IC (TOP245P) and PC817A optocoupler is proposed for the switch-mode power supply (SMPS) (applicable to LED driver) design and simulation. An analog behavioral model of the TOP245P IC including the shunt regulator, undervoltage(UV) detection, over-voltage(OV) shut-down and SR flip-flop is developed by using PSPICE. The empirical equation of PC817A curre...

System designers are being asked to reduce overall power in order to lessen the impact on our environment, while reducing both capital and operating costs. They are also being asked to increase circuit density so that electronic systems can be pushed into smaller form factors and operate in harsher environments. Unfortunately, incorporating high power solutions into these systems causes signifi...

The power supply designer is continually being pressured to provide units which have higher efficiency, better regulation, less EMI and RFI, and smaller size and weight, all at a lower cost. The solution to this problem is a combination of circuit topology, layout, and supply control. This application note will address output control techniques for linear and switch mode power supplies (SMPS). ...

Current mode control as usually implemented in switching power supplies actually senses and controls peak inductor current. This gives rise to many serious problems, including poor noise immunity, a need for slope compensation, and peak-to-average current errors which the inherently low current loop gain cannot correct. Average current mode control eliminates these problems and may be used effe...

Switch-mode power supplies represent a particular class of variable structure systems (VSS). Thus, they can take advantage of non-linear control techniques developed for this class of systems. In this paper the so called sliding mode control is reviewed and its application to switchmode power supplies is discussed. Sliding mode control extends the properties of hysteresis control to multi-varia...