Abstract: A power supply apparatus and method for an active matrix organic light emitting diode (AMOLED) is disclosed. The power supply apparatus supplies power to the AMOLED while using a switching frequency varied in accordance with a clock signal, and includes a load checker for comparing a load current of the AMOLED with a first reference voltage, and outputs a result of the comparison as a load check signal, and a frequency oscillator for generating the clock signal which has a variable frequency in response to the load check signal. The power supply apparatus is switched in accordance with a clock signal having a frequency modulated based on a load condition of the AMOLED, for example, a load current. Accordingly, it is possible to reduce switching power loss caused by unnecessary power consumption under the condition that a small load current is generated, thereby achieving an enhancement in efficiency.

Abstract: A voltage regulator uses a comparing apparatus having hysteresis characteristics. The voltage regulator includes a comparator for comparing a comparison voltage with a reference voltage, and outputs a result of the comparison; a switching controller for generating a plurality of switching signals in response to the comparison result; resistors connected in the form of a string, to divide the comparison voltage into a plurality of voltages; and a switching box for selecting one of the plural voltages, as the comparison voltage, in response to the switching signals.

Abstract: An apparatus for transferring serial data (e.g., a serial interface using a single wire) generally includes a detector configured to detect a first level time period and a second level time period of an input signal, and a computing unit configured to compute a duty or duty cycle of the input signal and generate an output signal based on the duty or duty cycle.

Abstract: A slope compensation circuit includes an oscillator for generating a first clock signal having a reference frequency, a ramp signal generator for generating a ramp signal having a duty ratio of about 50% or higher based on the first clock signal, and a slope compensation signal generator for outputting a slope compensation current based on the ramp signal.

Abstract: An apparatus for transferring serial data (e.g., a serial interface using a single wire) generally includes a detector configured to detect a first level time period and a second level time period of an input signal, and a computing unit configured to compute a duty or duty cycle of the input signal and generate an output signal based on the duty or duty cycle.

Abstract: A power supply apparatus and method for an active matrix organic light emitting diode (AMOLED) is disclosed. The power supply apparatus supplies power to the AMOLED while using a switching frequency varied in accordance with a clock signal, and includes a load checker for comparing a load current of the AMOLED with a first reference voltage, and outputs a result of the comparison as a load check signal, and a frequency oscillator for generating the clock signal which has a variable frequency in response to the load check signal. The power supply apparatus is switched in accordance with a clock signal having a frequency modulated based on a load condition of the AMOLED, for example, a load current. Accordingly, it is possible to reduce switching power loss caused by unnecessary power consumption under the condition that a small load current is generated, thereby achieving an enhancement in efficiency.

Abstract: A slope compensation circuit includes apparatus includes an oscillator for generating a first clock signal having a reference frequency, a ramp signal generator for generating a ramp signal having a duty ratio of about 50% or higher based on the first clock signal, and a slope compensation signal generator for outputting a slope compensation current based on the ramp signal.

Abstract: A voltage regulator uses a comparing apparatus having hysteresis characteristics. The voltage regulator includes a comparator for comparing a comparison voltage with a reference voltage, and outputs a result of the comparison; a switching controller for generating a plurality of switching signals in response to the comparison result; resistors connected in the form of a string, to divide the comparison voltage into a plurality of voltages; and a switching box for selecting one of the plural voltages, as the comparison voltage, in response to the switching signals.