Electronic components are often assembled and interconnected on a flat surface known as a circuit board. The several types of existing circuit boards may be divided into two broad categories: those intended for prototype or experimental circuits; and those intended for production and/or commercial sale. Circuit boards used for experimental work are often referred to as breadboards or protoboards. Breadboards allow engineers to construct circuits quickly, so that they can be studied and modified until an optimal design is discovered. In a typical breadboard use, components and wires are added to a circuit in an ad hoc manner as the design proceeds, with new data and new understanding dictating the course of the design. Since breadboard circuits exist only in the laboratory, no special consideration need be given to creating reliable or simple-to-manufacture circuits – the designer can focus exclusively on the circuits behavior. In contrast, circuit boards intended for production or commercial sale must have highly reliable wires and interconnects, permanent bonds to all components, and topographies amenable to mass production and thorough testing. And further, they must be made of a material that is reliable, low-cost, and easy to manufacture. A fiberglass substratewith copper wires (etched from laminated copper sheets) has been the PCB material of choice for the past several decades. The Digilent board is a simple example of such a board. Note that most often, production circuit board designs are finalized only after extensive breadboard phases. Components are permanently affixed to production boards using the soldering process.
As discussed earlier, a digital circuit represents and manipulates information encoded as electric signals that can assume one of two voltages – logic-high voltage (or Vdd) and logic-low voltage (or GND). A digital circuit requires a power supply that can produce these two voltages, and these same supply voltages are also used to encode information in the form of two-state, or binary signals. Thus,if a given circuit node is at Vdd, then that signal is said to carry a logic ‘1’; if the node is at GND, then the node carries a logic ‘0’. The components in digital circuits are simple on/off switches that can pass logic ‘1’ and logic ‘0’ signals from one circuit node to another. Most typically, these switches are arranged to combine input signals to produce an output signal according to basic logic relationships. For example, one well-known logic circuit is an AND gate that combines two input signals to produce an output that is the logic AND of the inputs (i.e., if both input1 and input2 are a ‘1’, then the output is a ‘1’).
Altrushare - Wiring Diagram Gallery
Copyright © 2003 - 2018 Domain Media. All sponsored products, company names, brand names, trademarks and logos arethe property of their respective owners.