Ever imagined how the street lights would turn on automatically in the evening and go off in the morning? Is there anyone who comes early morning to turn off [[wysiwyg_imageupload::]]these lights? The following circuit based project can perform this job properly. In this circuit, the output pin of the comparator goes high depending on the configuration of LDR so that it can be made light or dark activated. This output is connected to a transistor T1 (BC 547) which acts as a switch for the relay. This circuit uses the output from a simple light/dark activated circuit and drives a relay in its output which can be further coupled to switch on/off an electrical appliance in a household. An appliance can be made dark or light activated by slightly changing the circuit’s configuration. This idea finds numerous applications such as, automatic watering of gardens at evening, automatic night lamp, dark activated siren and so on. Read on more to find out how the circuit is made and how it works.
Ever wanted to make your own table lamp? If yes then you have come to the right tutorial! This project shows you how to make table lamp using a bunch of LEDs and 555 Timer circuit. Our first problem is that we can’t give 12V directly to an LED which would simply burn it. Well you may say that adding a series resistor would solve that problem but let’s see what happens when we do that.
This circuit is based on Light Dependent Resistor (LDR) which will turn on LED’s whenever darkness is sensed in room. You can put this small lamp in your child’s room as a simple emergency lamp to avoid panic situation in case of sudden power failure. As it provide ample of light in the room so that your child can easily come out of room. Important feature of this circuit is it automatically become on by sensing the darkness so no need to search for switch.And it is powered by a rechargeable battery which charges automatically by the AC power supply so no need to worry about the battery backup. You can use adapter readily available in market or make your own. And when light comes it automatically off the lamp so need to off the lamp manually.
The white LED notepad lamp will help you to note down the message, telephone number or address in darkness. You can keep it near your telephone so that in night you can easily right the message. To switch on the light just press the switch S1 and it will on the light for specific interval of time and light will switch off again automatically. This circuit is potable; because of its small size you can easily put this in your pocket or purse and can be used in emergency like in power failure.This simple circuit is based on three transistors with few more components. Important feature of this circuit is in standby mode no transistor will conduct hence longer battery life.
NE555 astable generates a clock for the circuit, which provides an oscillating wave to the output pin 3 of IC1. You can vary the speed of oscillation with the help of VR1. The frequency of oscillation of 555 timer can be calculated by: f=1.44/(R1+2*(VR1)*C1) Now this wave is supplied to CD4017 decade counter pin 14…
Shown here is a low power consuming LED lamp circuit which starts to grow after light intensity goes below a threshold level of detection. This is not a switch [[wysiwyg_imageupload::]]based circuit, thus needs no human interference in order to turn it ON or OFF. Circuit is based on IC CA3140 which is a operational amplifier which combine the voltage of PMOS transistor with high voltage bipolar transistor on single chip, Light depending resistor(LDR) whose resistance dependent upon the amount of light falling on it and few more components. The circuit uses an operational amplifier CA3140 whose pins 2 and 3 act as inverting and non inverting inputs. Keep on reading to find out how the circuit is constructed and how it works.
During the last two decades, organic light-emitting diodes (OLEDs) have attracted considerable interest owing to their promising applications. They have already made inroads into the displays used for mobiles, PDAs and OLED TVs are also available in the market. Soon, OLEDs will be replacing incandescent and fluorescent lamps. Fig. 1: Image Showing a Regular…
The dazzling Water Cube swimming arena at last summer’s Beijing Olympics was lit up by around half a million LEDs. Famous Bridges, buildings and hotels are opting LEDs for their exquisite night lighting and general illumination too. Why there is this sudden rage for the tiny LED? A little light emitter, a well renowned indicator that faithfully served in the display units of calculators, digital watches, and mobile phones for years is now geared up to take away the headache of efficient as well as Eco-friendly lighting.Yes, the tiny LED is all set to light our lives. It has taken a giant leap, from being a humble indicator to on the way to monopolize the lighting market. Years of research has brought LEDs to this advanced stage.
LED bulbs are the future of lighting. Be it automobiles, industries, household or any hobbyist requirement, LEDs form the best solutions in terms of long-term cost savings and power efficiency. Not only are these devices more efficient than traditional lighting devices, they are built to outlast any of their lighting predecessor. The internals of a typical LED bulb will be explored here.Externally, a LED bulb might look similar to a conventional incandescent lamp, but the two are quite different. The chassis of the bulb is made of ceramic and houses the electronic ballast. Ceramic is used for its insulating and heat dissipative properties.
This circuit is based on the phenomenon of Push-ON and Auto-OFF. This means that when the circuit is switched ON, it will remain ON for specific period of Night Lamp with Timer for Stairs>time and then it will turn OFF automatically. Again to switch ON the circuit the user has to push the button ON…
Ever imagined how the street lights get turned ON automatically in the evening and gets switched OFF in the morning? Is there anyone who comes early morning to turn off these lights? The following circuit can perform this job properly. This project uses the output from a simple light/dark activated circuit known as LDR (Light Dependent Resistor) and drives a relay in its output which can be further coupled to switch on/off an electrical appliance in a household. An appliance can be made dark or light activated by slightly changing the circuit’s configuration. This idea finds numerous applications such as, automatic watering of gardens in evening, automatic night lamp, dark activated siren and so on.
CFL (Compact Fluorescent Lamp) converts electrical energy to radiant energy. They are energy efficient and use better technology as compared to conventional tube lights and bulbs.It has two components – a glass tube filled with argon & mercury vapor which is coated with a layer of fluorescent material; and an electronic ballast circuit.The ballast circuit takes a 220 V input from external power source and sends a current into the fluorescent tube as output. When power supply is given to the CFL, filament attached with the cathode heats up and emits electrons in the tube. This ionizes the argon and mercury vapor particles.