Abstract:
Disclosed are a digital-analog converter, a device for driving a liquid crystal display device including the digital-analog converter, and a liquid crystal display device. The digital-analog converter generates a grayscale voltage corresponding to a digital signal applied from the outside from a plurality of reference grayscale voltages and outputs the grayscale voltage. To this end, the digital-analog converter includes an intermediate grayscale voltage selection unit for selecting two intermediate grayscale voltages from among the reference grayscale voltages and a grayscale voltage generation unit for generating the grayscale voltage from the intermediate grayscale voltages, wherein the grayscale voltage generation unit generates the grayscale voltage according to preset k bits among m bits of the digital signals. Furthermore, the intermediate grayscale voltage selection unit includes a first selection unit for selecting a first intermediate grayscale voltage using a decoder of m-k bits excluding k bits from m bits and a second selection unit including a plurality of decoders from a 1-bit decoder to an (m-k-1) bit decoder to select a second intermediate grayscale voltage different from the first intermediate grayscale voltage. As described above, the second selection unit of the intermediate grayscale voltage selection unit is formed of not a single decoder corresponding to the number of provided bits but a plurality of decoders having smaller number of bits, and thus, the number of required transistors can be remarkably reduced. [Reference numerals] (AA) 1-bit decoder; (BB) 2-bit decoder; (CC) 3-bit decoder; (DD) 4-bit decoder
Abstract:
A continuous time sigma-delta analog to digital converter according to a desired embodiment of the present invention includes: a loop filter which has one or more amplifiers; a quantization unit for quantizing signals from the loop filter; a signal detection unit for detecting signals from the quantization unit; and a loop filter stabilization unit for receiving signals from the signal detection unit and adjusting an output of the loop filter. According to the continuous time sigma-delta analog to digital converter to a desired embodiment of the present invention, the continuous time sigma-delta analog to digital converter showing stable circuit operation characteristics without causing oscillations even though a signal which exceeds a predetermined intensity instantaneously, is inputted as an input of the continuous time sigma-delta analog to digital converter by detecting a peak signal of an output stage of the converter and controlling an output of the loop filter can be provided. [Reference numerals] (20) Loop filter; (30) Quantization unit; (60) Signal detection unit; (70) Loop filter stabilization unit
Abstract:
PURPOSE: A digital-to-analog converter is provided to prevent digital noise generated in a digital circuit from leaking into an analog circuit by separating the digital circuit and the analog circuit while optically transmitting signals therebetween. CONSTITUTION: A digital optical conversion unit(30) receives parallel digital signals consisting of multiple parallel bits and outputs the same number of parallel optical signals as the inputted bits by generating optical signals corresponding to 1 and 0 values of each bit for each parallel bit. An optical control switching unit(40) is provided with the same number of current sources(I1-N) and switches(SW1-N) as the bit number of the optical signals and performs simultaneous switching for the current sources to output. A current overlaying unit(50) generates analog signals by simultaneously overlaying the outputted current sources of the optical control switching unit to corresponding digit values with weights. [Reference numerals] (1) Digital signal unit; (10) Digital audio signal decoder; (2) Analog signal unit; (20) Latch; (30) Digital optical conversion unit; (40) Optical control switching unit; (50) Current overlaying unit; (60) Current voltage conversion/filter; (AA) Digital audio signal; (BB) Optical signal; (CC) Analog audio signal;
Abstract:
본 발명은 가변 이득 증폭기를 갖는 ADC에 관한 것으로서, 복수의 FLASH ADC들과 복수의 MDAC들을 포함하는 N(N은 자연수) 단으로 구성된 파이프라인 구조의 ADC에 있어서, 첫 번째 단의 제 1 FLASH ADC와 첫 번째 단의 제 1 MDAC에 입력신호가 입력되기 전에, GCB에 의해 제어되고, 이득 조절 기능을 갖는 VGA를 포함하는 것을 특징으로 하고, VGA는 복수의 단위 샘플링 커패시터들을 포함하고, ADC의 입력신호를 샘플링하는 커패시터와 GCB에 의해 선택된 적어도 하나 이상의 단위 샘플링 커패시터를 이용하여 이득을 조절하는 것을 특징으로 하며, 다양한 시스템에 응용이 가능하도록 이득 조절 기능을 갖고, AFE 응용시 전력 소모 및 면적을 최소화할 수 있다.
Abstract:
본 발명은 캐패시터의 직렬연결을 이용하여 멀티플라잉 디지털 아날로그 변환기의 구성에 사용되는 캐패시터의 숫자를 줄여 칩 면적과 소모 전력을 줄인 멀티플라잉 디지털 아날로그 변환기 및 이를 이용한 파이프라인 아날로그 디지털 변환기에 관한 것으로, 본 발명에 따른 멀티플라잉 디지털 아날로그 변환기는 샘플링페이즈에서 입력전압을 입력받고 증폭페이즈에서 상기 샘플링페이즈에서 보다 캐패시턴스 값이 줄어드는 제1캐패시터부; 상기 샘플링페이즈에서 상기 입력전압을 입력받고 상기 증폭페이즈에서 디지털 전압을 입력받는 제2캐패시터부; 및 상기 샘플링페이즈에서 상기 제1캐패시터부와 상기 제2캐패시터부가 입력받은 입력전압과 상기 증폭페이즈에서 상기 제2캐패시터부가 입력받은 디지털전압의 차이를 증폭한 레지듀 전압을 출력하기 위한 증폭부를 포함하고, 상기 제1캐패시터부는 상기 증폭페이즈에서 상기 증폭부의 입력노드와 출력노드사이에 네거티브 피드백 루프를 이루는 것을 특징으로 한다.
Abstract:
PURPOSE: A digital to analog converter is provided to converts a plurality of digital signals to each analog signal by using a fine resistance string and to share fine resistance string. CONSTITUTION: A conversion unit includes a switching unit(GSC), and a resistive unit(GMF), and a fine switching unit(GSF). The switching unit generates a plurality of fist high voltage and first a low voltage. The fine switching unit is connected between a first high voltage and a first low voltage. The fine switching unit includes resistances which generates a plurality of first fine voltages. The fine switching unit generates the first analog signal and the second analog signal.
Abstract:
A circuit for a low voltage CMOS digital to analog converter is provided to be operated at a low voltage by using transistors less than two between a supply voltage and a ground. A digital signal complementation converting part(610) converts a digital signal into an inverted signal and a non-inverted signal. A weighted value current mirror part(620) includes an input terminal transistor and a plurality of output terminal transistors. A plurality of output terminal transistors generates an output current of a value multiplying a reference current value by a fixed weighted value. A plurality of switch parts includes a first switching transistor and a second switching transistor. The first switching transistor turns on/off a spot between a gate of the output terminal transistor and a gate of the input terminal transistor by the non-inverted digital signal generated in the digital signal complementation converting part. A current to voltage converting part(660) converts the output current into an analog voltage.
Abstract:
A delta sigma modulator is provided to reduce size and current consumption while maintaining resolution by reducing the size of an integration capacitor. A delta sigma modulator includes an amplifying unit, and unit integrators. The amplifying unit adjusts amplification degree according to the ratio of sampling capacitors and integration capacitors. The unit integrators have switches which constitute the paths of the capacitors and the amplifying unit. The size of the sampling capacitor which constitutes the unit integrator of the last end, is smaller than the sampling capacitor of the adjacent unit integrator.
Abstract:
디지털-아날로그 변환기가 개시된다. 다수의 디지털 제어신호들에 응답하여 아날로그 전압들을 발생시키기 위한 디지털-아날로그 변환기는 아날로그 전압들을 출력하기 위한 제1단자, 및 제2단자 사이에 직렬로 접속된 다수의 제1저항들, 각각이 상기 직렬로 접속된 다수의 제1저항들 중에서 대응되는 두 개의 저항들 사이에 형성된 다수의 노드들, 및 다수의 제2저항들을 구비하며, 상기 다수의 제2저항들 각각의 제1단은 상기 제1단자, 상기 다수의 노드들 중에서 대응되는 노드, 및 상기 제2단자에 접속되고, 상기 다수의 제2저항들 각각의 제2단은 대응되는 디지털 제어신호를 수신한다. 본 고안에 따른 디지털-아날로그 변환기는 다수의 저항들로만 구성되므로, 다수의 반도체 소자들을 구비하는 종래의 디지털-아날로그 변환기에 비해 통신회선의 주파수 특성 변화에 신속하게 반응하고, 저전력 소모 및 통신장치의 소형화가 가능하며, 불량률도 낮다. DAC, 디지털-아날로그 변환기, 모뎀, 통신장치
Abstract:
PURPOSE: A sample-and-hold amplifier using a bootstrapping method and a CMOS A/D converter including the same are provided to maintain the resolution of 8bits for input signals of 500MHz by applying the bootstrapping method to the sample-and-hold amplifier. CONSTITUTION: An A/D converter includes a sample-and-hold amplifier(11), the first A/D converter(13), an MDAC(Multiplying Digital-to-Analog Converter)(12), the second A/D converter(14), and a digital correction logic circuit(15). The sample-and-hold amplifier is used for sampling an analog input signal. The first A/D converter is used for converting the sampled signal to the first digital output code of plural bits. The MDAC is used for storing the sampled signal and amplifying a difference between the stored signal and an analog signal corresponding to the first digital output code. The second A/D converter is used for converting an output signal of the MDAC to the second output code of plural bits. The digital correction logic circuit is used for receiving the first and the second output codes, reiterating one bit of the second digital output code on one bit of the first digital output code, and outputting a final digital output code, namely the remaining bits except for the reiterated bit.