9 documents in category: Digital tagged with:
Clear results

A collection of electronic components that have been assembled and interconnected to perform a given function is commonly referred to as a circuit. Electronic circuits can be divided into two broad categories: digital and analog.

A digital circuit is constructed of a power supply, devices, and conduction nets. Some nets provide circuit inputs from the “outside world”; in a schematic, these input nets are generally shown entering the left side of component and/or the overall circuit.

A signal in a digital circuit is a circuit net that transports an output voltage from one device to one or more input connections of other devices. In a digital circuit, signals are constrained to be at one of two voltages, either Vdd or GND. Thus, all data in digital circuits are represented by signals that can be in one of only two states, and all data operations combine two-state data inputs to produce two-state data outputs.

A digital circuit represents and manipulates information encoded as electric signals that can assume one of two voltages: logic high (Vdd) or logic low (GND). Here we will dig further into the workings of digital circuits now that you have a better foundation for understanding.

Digital electronic circuits are built from electronic switches that are called transistors instead of the mechanical switches and resistors, as discussed in the previous sections. The basic concept is the same—the switches (transistors) are arranged so that they can be turned on or off by signals carrying either LLV or LHV.

Armed with the basic understanding of FET operation as described in previous sections, it is possible to construct a basic logic circuit that forms the back bone of all digital and computer circuits. These logic circuits will combine one or more input signals to produce an output signal according to the logic function requirements.

The XOR function is frequently used in digital circuits to manipulate signals that represent binary numbers.

A digital logic circuit consists of a collection of logic gates; the input signals that drive them, and the output signals they produce. The behavioral requirements of a logic circuit are best expressed through truth tables or logic equations, and any design problem that can be addressed with a logic circuit can be expressed in one of these forms.

This project exercise presents several worded problems that serve as behavioral specifications for digital circuits. Your job is to design, simulate, and download those circuits to your board. The topics from this exercise are based off of the material presented in Real Digital Project 4.