Abstract: Provided is a testing circuit capable of testing functionality of various DC-DC converters without an inductor. According to the present invention, various electronic elements forming the testing circuit for a DC-DC converter are converted in the same kinds of elements or different elements in one-to-one or one-to-two or more correspondence to electronic elements forming a typical DC-DC converter. When the conversion is performed, the electronic values of the elements may be properly scaled to test the DC-DC converter without consuming high power. Therefore, various problems of the related art are minimized.

Abstract: The present invention relates to a battery parameter management system and a battery parameter estimation method which are capable of simply estimating parameters of elements forming a battery equivalent model having a simple structure. The battery parameter system includes an amperemeter, a voltmeter, a control switch unit, and a processor, and the battery parameter estimation method includes supplying a pulse current, estimating resistance of an internal resistor, estimating capacitance of an internal capacitor, and estimating parameters of dynamic elements.

Abstract: Provided are a battery state-of-charge (SOC) estimation method and a battery management system which are capable of estimating an SOC using an inexpensive processor and a small-capacity memory. The SOC estimation method includes an SOC table creation step, an SOC calculation step, an SOC comparison step, and a processing step. The battery management system includes a battery, a sensing resistor, a control switch unit, and a processor.

Abstract: The present invention introduces a device and a method for driving an LED with an improved power factor without using a voltage detector having a large amount of area and power consumption. The device for driving an LED includes a power supply unit, an LED array, and a current path select circuit. The LED array 320 is connected with the power supply unit in parallel and includes at least one LED string including LED channels LED1 to LEDn that are configured of a plurality of LEDs connected in series. The current path select circuit selects a path of current flowing from output terminals of the plurality of LED channels according to voltage levels of each of the output terminals of the plurality of LED channels.