what is ADC




What is a ADC

Analog to digital converters (ADC) are utilized broadly in signal processing systems for converting analog signals into digital signals. The function of an analog to digital converter (ADC) is to accurately convert an analog input signal into a digital output represented by a coded array of binary bits. The output bits are generated by processing the analog input signal through a number of comparator steps. An ADC receives an analog signal as input and provides (generates) a digital code corresponding to strength of the analog signal at various time instances as output. The number of bits in the generated digital code represents the resolution of the ADC. A reference signal is often used by an ADC in providing such conversions. The digital output signal represents a number that is proportional to the current magnitude and/or amplitude of the analog input signal. A/D converters are often used with microprocessors to convert an analog signal to a corresponding digital signal which is processed by the microprocessor. A/D converters of the parallel type and the serial and parallel type are advantageous for high speed operation. Such A/D converters generally comprise a plurality of comparators for comparing an analog input signal with analog reference voltages and an encoder for converting output signals of the comparators to a multibit digital signal. Multi-stage pipelined analog to digital converters provide efficient high speed conversion of analog signals to digital equivalents. A/D converters are employed in a wide variety of applications. Many modern electronic systems require conversion of signals from analog to digital or from digital to analog form. Circuits for performing these functions are now required in numerous common consumer devices such as digital cameras, cellular telephones, wireless data network equipment, audio devices such as MP3 players, and video equipment such as DVD players, high definition digital television (HDTV) equipment, and etc. For example, ADCs are often used in audio recording equipment to convert analog audio signals into digital signals that can be stored on digital media. Also, ADCs are usually employed to convert a received wireless (analog) signal into a digital signal for further processing by other components in a mobile device. Wireless communications products and other modern electronic devices typically process and generate both digital and analog signals. To perform their intended functions, these systems often convert analog signals into digital signals.