Electronics

USB Reading Lamp

Posted on

USB reading lamp is powered using USB port. The USB port provide 5 v and 100mA which is sufficient for this circuit. Cut the one end of the USB cable and use RED(pin1) and Black(pin4) for 5v positive and negative respectively.   Parts c1,c2 – 100 mF 25 v Zener diode – 4.7v 400m R1- […]

Electronics

10 Stage LED Sequencer

Posted on

10 Stage LED Sequencer Components   IC1- CD4017 IC2- NE555 C1 – 1μ C2- 0.01 μ R1 – 470 Ω R2 – 100 KΩ R3- 100 Ω LED1-10 – RED LED 9volt DC power supply.                               For power supply you can use 9 volt […]

Electronics

Variable DC Power Supply using LM317

Posted on

Below is the circuit for variable dc power supply R1- 240 Ω R2- 5K VR R2 can be replaced by fixed value resistor for fixed power supply. Following formula can be used to calculate output voltage. Vo=1.25(1+R2/R1) Output voltage should be2 voltage greater than input. Parts for current setup  D1, D2 – 1N4001 C1-0.1 μ C2 – […]

Electronics

20 Watt Inverter

Posted on

This circuit will drive a 40 watt fluorescent or two 20-watt tubes in series. The transformer is wound on a ferrite rod 10mm dia and 8cm long. The wire diameters is 0.61mm wire for the primary and 0.28mm wire for the secondary and feedback winding. The circuit will take approx. 1.5amp on 12v, making it […]

Electronics

Lamp Dimmer

Posted on

12v LAMP Dimmer Parts IC 1 – NE555 Transistor – 2N2955 -1 Resistance – 1k(2 no.), 100 Ω Variable Resistance – 50k Capacitor – 0.1 µF Diode – 1N4001 – 3  12v 2 amp Bulb Input Voltage is 12v. To create your own bench top power supply use the circuit shown in http://digitalab.org/2012/06/regulated-dc-power-supply-circuit/  

Electronics

LED Basics

Posted on

Today LED has become an integral part of consumer electronics. LED TV, LED Display, LED Lights and so on. These are becoming very popular because of there low power consumption. What is LED? LED stands for Light emitting diode. A light emitting diode is essentially a PN junction semiconductor diode that emits a monochromatic(single) colour […]