analog-to-digital converter

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Related to analog-to-digital converter: A/D converter, A/D conversion

analog-to-digital converter

[¦an·əl‚äg tə ¦dij·ət·əl kən′vərd·ər]
A device which translates continuous analog signals into proportional discrete digital signals.

Analog-to-digital converter

A device for converting the information contained in the value or magnitude of some characteristic of an input signal, compared to a standard or reference, to information in the form of discrete states of a signal, usually with numerical values assigned to the various combinations of discrete states of the signal.

Analog-to-digital (A/D) converters are used to transform analog information, such as audio signals or measurements of physical variables (for example, temperature, force, or shaft rotation) into a form suitable for digital handling, which might involve any of these operations: (1) processing by a computer or by logic circuits, including arithmetical operations, comparison, sorting, ordering, and code conversion, (2) storage until ready for further handling, (3) display in numerical or graphical form, and (4) transmission.

If a wide-range analog signal can be converted, with adequate frequency, to an appropriate number of two-level digits,or bits, the digital representation of the signal can be transmitted through a noisy medium without relative degradation of the fine structure of the original signal. See Computer graphics, Data communications, Digital computer

Conversion involves quantizing and encoding. Quantizing means partitioning the analog signal range into a number of discrete quanta and determining to which quantum the input signal belongs. Encoding means assigning a unique digital code to each quantum and determining the code that corresponds to the input signal. The most common system is binary, in which there are 2n quanta (where n is some whole number), numbered consecutively; the code is a set of n physical two-valued levels or bits (1 or 0) corresponding to the binary number associated with the signal quantum.

The illustration shows a typical three-bit binary representation of a range of input signals, partitioned into eight quanta. For example, a signal in the vicinity of 3/8; full scale (between 5/16 and 7/16) will be coded 011 (binary 3).

A three-bit binary representation of a range of input signalsenlarge picture
A three-bit binary representation of a range of input signals
References in periodicals archive ?
The analog-to-digital converter section uses surface mount construction on standard G10 epoxy glass circuit board.
The board includes an NXP LPC1769 ARM Cortex-M3 microcontroller (the "target" microcontroller) with 512 kBytes of flash memory, 64 kBytes of SRAM, a 12-bit analog-to-digital converter (ADC), a 10-bit digital-to-analog converter (DAC), and Ethernet and USB connectivity.
The board features two analog RF inputs with 125MS/s sampling rate and a 14-bit analog-to-digital converter (ADC), two analog RF outputs with 14-bit digital-to-analog converter (DAC), Ethernet, USB, and two sets of 26-pin extension connectors.
It can wake-up from its low-power sleep mode with the CPU operating at 25 MIPS and ready to make an analog-to-digital converter (ADC) measurement within 2 [micro]s.
The microcontroller integrates high-performance analog peripherals, including an internal temperature sensor, four operational amplifiers, four low-power comparitors, a 16-bit analog-to-digital converter (ADC), and two 12-bit digital-to-analog converters (DACs), and two 8-bit DACs.
The series also includes a targeted peripheral set featuring an up to eight channel, fast 2.8 [micro]ms successive approximation register (SAR) analog-to-digital converter (ADC), an on-chip 20 MHz internal precision oscillator and 100 bytes of non-volatile data storage (NVDS) for storing system parameters or user data.
Designed for diagnostic control of tunable laser optical module applications as well as data acquisition and instrumentation, the ADuCM310 is a multidie stack, on-chip system that integrates a 16-bit (14-bit accurate) multichannel successive approximation register (SAR) analog-to-digital converter (ADC), an ARM Cortex-M3 processor, eight voltage output digital-to-analog converters (VDACs), six current output DACs, and flash/EE memory.
The TI PGA900 sensing conditioner, now available from Mouser Electronics, manipulates its input signals by amplification and digitization through two analog front end channels, each containing a low-noise 24-bit analog-to-digital converter (ADC), to enable high-resolution signal acquisition.
Contract notice: Comprehensive patent office service aimed at getting national and international patent protection for inventions group for asynchronous (bezzegarowego) analog-to-digital converter with a redistribution of cargo with reduced compared pojemosci - kc-zp.272-404 / 15.
These devices integrate a current amplifier, a 50 Hz/60 Hz rejection filter to eliminate artificial light flicker and a 15-bit ADC (analog-to-digital converter).
The 15 22 mm device integrates analog-to-digital converters (ADCs), digital-to-analog converters (DACs), and EEPROM and features remote configurability and telemetry-monitoring of power management parameters over a PMBus protocol.
The Italian authors discuss branching, capacity improvement, modulations and coding, countermeasures against imperfections in TX and RX chains, low noise amplifiers, local oscillators, analog-to-digital converters, power amplifiers, upconversion, linearization techniques, and parabolic antennas.