AY24S1 E250 W06 notes

Any continuous signal for which the time varying feature of the signal is a representation of some other time varying quantity.

An Analogue - to - Digital Converter (ADC) takes an analogue input voltage and after a certain amount of time produces a digital output code that represents an analogue input.

It is the highest-speed ADC available but requires much more circuitry than the other types. For example, a 6-bit flash ADC requires 63 analogue comparators, while an 8-bit unit requires 255 comparators and a 10-bit converter requires 1023 comparators. The large number of comparators has limited the size of flash converters. IC flash converters are commonly available in 2-to-8 bits.

The process of converting digital signals into analogue signals.

Digital broadcast generally offers better quality than analogue broadcast due to its ability to transmit higher resolution video and audio signals without degradation.

A type of analog to digital converter whose conversion time is dependent on clock frequency and is required to go through from 000 even if the signal is at a higher range, making it time-consuming.

In general, for an N-bit DAC, the number of different levels will be 2^N, and the number of steps will be 2^N - 1.

The voltage being measured or converted by the ADC, in this case 5V.

The resolution of a DAC refers to the number of bits used to represent the analog output signal, and higher resolution leads to higher accuracy in the converted signal.

Represented by continuously change (smooth change) in level throughout some range.

Digital Video Broadcast (DVB) is a digital broadcasting technology that transmits audio and video signals to television sets using digital signals rather than analog signals.

The time taken for an analog signal to be converted into a digital signal or vice versa.

A filter used to remove or reduce the aliasing effect in sampled signals.

A type of analog-to-digital converter that converts an input voltage into a digital output using a bank of comparators and a priority encoder.

The number of digital bits used to represent the analog input voltage in a flash ADC, in this case, 3 bits are used to represent 7 levels corresponding to 1V, 2V, 3V, ... and 7V.

A digital circuit that generates a binary code based on the highest priority active input line, used in flash ADC to produce the digital output based on the comparator outputs.

A/D Conversion refers to the process of converting an analogue signal into a digital format, while D/A Conversion refers to the process of converting a digital signal into an analogue format.

A signal in which a continuous quantity is represented by a discrete function which can only take on one of a finite number of values.

A type of analogue to digital converter that uses a linear ramp to perform the conversion process.

A circuit that converts digital signals into analog signals.

Continuous signals that represent physical quantities such as sound, light, and temperature.

Representation of information using discrete values, often in the form of binary digits (0 and 1).

The process of converting analogue signals to digital form, involving sampling and quantization.

The ADC produces digital output with 4 bits, allowing for 2^4 or 16 possible digital values.

The change in the analog input voltage that will cause a change in the digital output of the ADC, in this case, the step size is 1V.

Sound is a pattern of pressure waves carried through the air, such as music and talking.

A device that senses how the air pressure varies and generates a pattern of voltage fluctuations.

Represented by discrete steps (jumps). Constant level if you choose a small enough time scale.

The resolution of DAC is defined as the smallest change that can occur in the analogue output as a result of a change in the digital input.

Discrete signals that represent information in the form of a sequence of symbols or numbers, and are less susceptible to noise and interference.

The process of converting continuous analog signals into discrete digital representations using sampling and quantization.

Resolution, accuracy, conversion time, and input bandwidth are crucial factors to consider in an ADC conversion.

The digital inputs D, C, B, and A are from the output register of the digital system. These 4 bits produces 2^4=16 different numbers.

The process of converting digital data back into an analogue signal, such as music or voice, for playback.

The maximum voltage level that a system is designed to handle, often used as a reference for analog-to-digital converters (ADCs) and digital-to-analog converters (DACs).

A type of analogue to digital converter that uses a bank of comparators to quickly determine the input voltage.

Continuous signals that vary in time and amplitude, representing physical quantities such as sound, light, and temperature.

The output signal resulting from the conversion of digital input using a Digital-to-Analogue converter.

A constant value for a given Digital-to-Analogue converter connected to a fixed reference voltage supply.

Digital - to - Analogue (DAC) conversion is a process of taking a value represented in digital code (straight binary or BCD) and converting it to a voltage or current that is proportional to the digital value.

The rate at which the ADC performs the conversion process, in this case 1 MHz or 1,000,000 cycles per second.

The process of converting an analogue signal, such as music or voice, into a digital format for storage, for example, MP3.

Digital to Analogue Conversion (DAC) is the process of converting digital data into an analog signal.

One of the simplest version of the ADC. It uses a binary counter and allows the clock to increment the counter one step at a time until Vo ≥ Vin. It is called digital-ramp ADC because the waveform at Vo is a step-by-step ramp (a staircase like waveform). The digital-ramp ADC contains a DAC, an analogue comparator and a control AND gate. The comparator output serves as the active-LOW end-of-conversion signal.

The A/D conversion process is more complex and time consuming than the D/A process and many different methods have been developed and used.

Refers to the pattern of voltage fluctuations carried by wires and amplifiers, as in the case of a small loudspeaker in a telephone.

An amplifier used in D/A conversion that gives different weights to the binary inputs.

Continuous signals that vary in time and amplitude.

Analog to Digital Converter (ADC) is a device that converts continuous analog signals into discrete digital numbers.

The smallest change in output voltage that can be produced by a DAC.

When the counter is at 1112, the DAC output is at its maximum value of 7V; that is the Full-Scale Voltage (FSV).

The maximum voltage that an ADC can convert to a digital value, in this case 12V.

A circuit that samples the input analogue signal and holds its value until the next sample is taken.

An analog to digital converter that uses no clock signal, has almost instantaneous conversion, and the conversion time depends only on the propagation delays of the comparators and encoder logic, typically of the order of 15 - 20 ns.

The stage where the analogue signal is converted into a digital representation.

For D - A conversion an input for a voltage reference, V ref , is required. This reference voltage is used to determine the full - scale output or maximum voltage that the D - to - A converter can produce.

For each input number, the D - to - A converter output a unique voltage value. The analogue output voltage, V OUT is proportional to the input binary number.