3.1.4 Systems approach to designing GapFill

A systems approach to designing involves breaking down the process into a series of stages or steps. A simple system has three stages, the first one being the  decisionterminatorinputoutput.  ResistorsFlow chartsOpen loopsLDRs are used to represent systems graphically. Electrical components must be connected to a system to sense or detect an electrical input. A component that senses light is  a thermistoran LEDan LDRa resistor, and a thermistor senses  humiditylightheatpressure. Switches are also forms of electrical inputs. A  buzzerspeakermicrocontrollerlamp is one of the most versatile as a processor. It can be programmed to perform a wide range of functions such as  decision-makingdrillingclosed looptoggling operations. Speakers and buzzers are examples of  logic gatestimersoutputsinputs and convert electrical energy into sound waves. LEDs are replacing conventional light bulbs because they  are biggeruse less energycost lesshave no resistance. The D in LED stands for  distancediodedirectiondevice, which means that it will only allow current to pass through it in one direction. When several components have been joined up, they form a  processsensorcircuitchain. A system which makes use of  an LEDa thermistorlogic gatesfeedback is known as a closed loop system.