Abstract:
본 발명은 컨버터 스위치 피크전류 제어용 기준신호 생성회로, 절연 컨버터 및 컨버터 스위치 피크전류 제어용 기준신호 생성 방법에 관한 것이다. 본 발명의 하나의 실시예에 따라, 절연 컨버터의 1차측 공급전압으로부터 분배된 입력전압 신호에 데드-존을 형성하는 데드존 생성기; 2차측으로의 에너지전달 듀티비를 산출하는 듀티비 산출부; 및 듀티비 산출부로부터 산출된 에너지전달 듀티비를 이용하여 데드-존이 형성된 데드존 전압 신호로부터 컨버터 스위치의 피크전류 제어용 기준신호를 생성하여 출력하는 연산부;를 포함하는 컨버터 스위치 피크전류 제어용 기준신호 생성회로가 제안된다. 또한, 절연 컨버터 및 컨버터 스위치 피크전류 제어용 기준신호 생성 방법이 제안된다.
Abstract:
A piezoelectric actuator and a method for searching an optimum operating frequency using the same are provided to reduce a size of a circuit by only using an optimum operating frequency calculation unit and an FM(Frequency Modulation) unit for supplying the optimum operating frequency to the piezoelectricity. A piezoelectric actuator for driving a piezoelectricity(330) with two resonance points includes an optimum operating frequency calculation unit(310) and an FM unit(320). The optimum operating frequency calculation unit calculates the optimum operating frequency by adding a characteristic resonance frequency according to a characteristic analysis of the piezoelectricity to a delta frequency with a predetermined frequency difference from a first resonance frequency. The FM unit is connected to the optimum operating frequency calculation unit and generates the optimum operating frequency calculated by the optimum operating frequency calculation unit to supply the optimum operating frequency to the piezoelectricity.
Abstract:
An auto focusing apparatus is provided to detect the output signal of a driving signal generator, exclude the domain of a signal causing noise in the output signal of the driving signal generator, and feed the signal back to an ADC(Analog to Digital Converter), thereby suppressing the generation of the noise. An auto focusing apparatus(10) comprises a sensing unit(11), an ADC(12), a lens position controller(13), a driving signal generator(14), an operation unit(16), and an actuator(15). The sensing unit detects the current position of a lens(17) moving a predetermined range along a moving axis. The ADC converts the lens position value of the sensing unit into a digital signal. The lens position controller generates a signal for moving the lens to the target position of the lens determined by an auto focusing algorithm. The driving signal generator generates a square wave signal according to a signal in the lens position controller. The operation unit is connected to the ADC to control the converting time of the ADC according to the square wave signal of the driving signal generator. The actuator is driven by the square wave signal of the driving signal generator.
Abstract:
본 발명은 현재 구동주파수와 이전 구동주파수에 따른 렌즈배럴의 이동거리를 비교하여 피에조의 최적 구동주파수를 검색하는 검색방법에 관한 것이다. 본 발명에 따른 피에조의 최적 구동주파수 검색방법은, 피에조를 구동하기 위한 최적 구동주파수 검색방법에 있어서, a) 상기 피에조를 구동시키기 위한 구동주파수를 초기화하는 단계; b) 상기 구동주파수를 피에조에 공급하여 다수의 렌즈가 실장된 렌즈배럴의 위치를 이동시키는 단계; c) 상기 렌즈배럴의 이동에 따라 변화된 아날로그의 감지전압을 디지털의 위치값으로 변환하는 단계; d) 상기 변환된 현재 위치값에 이전 위치값을 감산연산한 연산값을 0과 비교하는 단계; 및 e) 상기 d) 단계에서 상기 연산값이 0보다 작을 경우, 이전 구동주파수를 최적 구동주파수로 판단하는 단계;를 포함한다. 피에조, 엑츄에이터, 공진점, 공진주파수, 구동주파수, 위치값
Abstract:
A method for setting a driving frequency of a piezo-actuator is provided to optimally drive the piezo-actuator without depending on characteristic changes due to the dispersion or the temperature between actuators and without an assembly state. A method for setting a driving frequency of a piezo-actuator includes the steps of: controlling generation of a lowest oscillation frequency within a previously set variable frequency(S100); driving the piezo-actuator by the use of a driving signal having a current oscillation frequency(S200); storing a variance by each oscillation frequency(S330) by detecting a variance of the piezo-actuator(S200); determining whether or not the oscillation frequency of the current driving signal is a highest oscillation frequency within the driving frequency range(S400); controlling generation of an oscillation frequency higher than the current oscillation frequency by a previously set one step if the oscillation frequency of the current driving signal is the highest oscillation frequency(S500); and setting a driving frequency by selecting a frequency corresponding to a highest variance among the variances for each frequency as an optimum driving frequency(S600).