This tutorial explains how to make your own power supply unit for all your electronics and embedded system experiments. It also has a backup battery which will be used in case of power cuts and a display.
Saving electricity is a major concern for domestic and industrial units. We always try hard to save electricity in many ways to reduce our electricity bills, but due to some known and unforeseen circumstances our efforts do not normally transform in saving electricity. Adding to our woes we may at times forget to switch off electrical gadgets when we are not using them, especially the AC’s, which not only results in mounting electricity bills, but also forget the fact that we are wasting a resource which is of National Importance.
Are you an electronic hobbyist? Then an adjustable power supply is a must for your various needs. This project explains how to make a LM317 based adjustable power supply unit with a digital display
Voltage regulator is a device which provides fix output voltage in spite of the variable input voltage supplied. It is a three terminal device. Voltage [[wysiwyg_imageupload::]]regulator basically comes in two different series: 78XX and 79XX. Voltage regulator under 78XX series are designed for positive inputs i.e. if while 79XX series are designed for negative inputs.. In market variety of voltage regulators are available with output as 6V, 9V, 12V, 15V etc. Voltage regulator can also withstand over current drawn due to short circuit or overheating. It will cut off the circuit before damage occurs. One must take care while mounting the regulator because reverse polarity may destroy the regulator.Pin configuration of negative and positive voltage regulator are shown in fig.
A simple circuit of variable power supply and charger is described here. It is useful when the main power supply is available or when there is no power supply.This circuit can be used for testing electronic projects at your work bench. It can be used to charge your mobile battery. It can be used as an emergency light. In this circuit you can take outputs by flipping the different switches according to your requirement. Engage switch S3 if you want a variable power supply as output. For variable power supply, we have used variable voltage regulator LM317whichis a 3 terminal adjustable positive voltage regulator. It will provide an output voltage in the range of 1.2V to 37V. For obtaining different voltages, adjust the variable resistor to see the output on the multimeter and set the required voltage. Range of power supply varies from 1.5V-12V.
The electronic devices are very sensitive to the fluctuations in the power fed to them. This problem can be solved by using regulated power supply for them. This [[wysiwyg_imageupload::]]project about power supply circuit is equipped with an adjustable voltage regulator to adjust the output in accordance with the requirement. Adjustable voltage regulators have both line and load regulation which is better than standard fixed regulators. The circuit is made using following active and passive electronic components: 1. Bridge Rectifier2. Resistors3. Capacitors 4. Variable Resistors.5. Linear Voltage Regulator IC