Abstract: A circuit for driving a gate of a power metal-oxide semiconductor field effect transistor (MOSFET), which uses a higher voltage than a gate controller is provided. The circuit is able to safely and effectively transmits an output signal of a gate controller irrespective of a frequency and a duty-cycle of the output signal when transmitting the output signal of the gate controller to the power MOSFET using a higher voltage than the gate controller. Accordingly, the circuit is suitable for a case where the duty-cycle of the output signal of the gate controller dramatically changes and the frequency is irregular.

Abstract: Provided are a circuit for and a method of eliminating pop noise in a digital audio amplifier using dual power supply, which are simple, drop in price, and can be readily implemented in a semiconductor chip. According to an existing technique, pop noise is eliminated using a relay. However, in the present circuit and method, pop noise is eliminated using the small number of discrete electronic devices. The circuit for eliminating pop noise controls a voltage at a gate of a power switch, i.e., a power MOS transistor, when power supply voltages are applied and the application of power supply voltages is stopped.

Abstract: Provided is a digital audio amplifier capable of increasing self-oscillation frequency by using a phase lead-lag compensator. The digital audio amplifier includes the phase lead-lag compensator which increases the self-oscillation frequency by lead-lag-compensating for the phase of an output signal and making a feedback of the compensated output signal. In addition, the digital audio amplifier further includes a bandwidth control means which controls the bandwidth of an error amplifier. Accordingly, the digital audio amplifier can adjust the self-oscillation frequency and reduce the extent to which the self-oscillation frequency varies in accordance with the variation of the output signal by using the bandwidth control means that inserts a pole into the error amplifier.

Abstract: Provided are a circuit for and a method of eliminating pop noise in a digital audio amplifier using dual power supply, which are simple, drop in price, and can be readily implemented in a semiconductor chip. According to an existing technique, pop noise is eliminated using a relay. However, in the present circuit and method, pop noise is eliminated using the small number of discrete electronic devices. The circuit for eliminating pop noise controls a voltage at a gate of a power switch, i.e., a power MOS transistor, when power supply voltages are applied and the application of power supply voltages is stopped.

Abstract: The present invention relates to amplifier combined digital amplifier using pulse width modulation and analog amplifier, and more particularly, to amplifier converting the analog input signal to pulse width modulation signal by comparing the analog input signal with triangle-wave, inputting the pulse width modulation signal to a dead time logic circuit, controlling the “ON”, and “OFF” operation of output transistor by output signal of the dead time logic circuit and converting the pulse width modulation signal of the output transistor to amplified analog signal using LC low pass filter. The present invention reduces the loss of efficiency of output transistor. Therefore the size of heat radiating plate can be easily reduced and amplifier with compact size can be accomplished by the present invention.

Abstract: Disclosed are flat panel field emitter displays whose unit cell structure adopt a planar cathode structure in stead of a conventional microtip structure, so as to increase the degree of integration and can be operated at low operation voltages at high speeds. In the structure, a channel insulator is formed below the cathode and underlaid by a gate. By means of the gate voltage, the electron emission from the cathode can be controlled. The electrodes in the structure are arranged in the order of anode, cathode and gate, allowing the simplification of processes. With the ease of controlling the distance between electrodes, the displays can be applied for almost all video systems from small sizes to large screen area displays, in place of conventional displays. The displays allows conventional semiconductor processes and facilities to be utilized as they are.

Abstract: The present invention relates to amplifier combined digital amplifier using pulse width modulation and analog amplifier, and more particularly, to amplifier converting the analog input signal to pulse width modulation signal by comparing the analog input signal with triangle-wave, inputting the pulse width modulation signal to a dead time logic circuit, controlling the “ON”, and “OFF” operation of output transistor by output signal of the dead time logic circuit and converting the pulse width modulation signal of the output transistor to amplified analog signal using LC low pass filter. The present invention reduces the loss of efficiency of output transistor. Therefore the size of heat radiating plate can be easily reduced and amplifier with compact size can be accomplished by the present invention.