LED Circuits
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This simple and cheap circuit is not just for Christmas! There are just two resistors, a small-signal transistor such as a BC547, one flashing` LED and a string of normal` LEDs. The flashing LED works as an oscillator and switches the transistor on and off;.... -
The term "mixed-signal" is usually reserved for circuits and ICs that process both analog and digital signals. In that sense the title "A mixed-signal LED clock" is perhaps misleading since this is a digital clock from beginning to end. However, the readout.... -
The AS3636 is a highly integrated Photoflash charger including IGBT driver, inductive DCDC boost autofocus/ video LED driver, an indicator LED driver and it includes system level ESD protection and a .... -
This is a simple LED blinking project using PIC16F877A. Basically there are only 2 LEDs, connected to PIC16F877A and the source code is being modified from the 16F template.... -
When the push switch is operated - the buzzer will sound and the LEDs will begin to flash. For the hearing members of the household - the buzzer acts as a regular doorbell. It also re-assures the visitor that the doorbell is working. When the push switch is.... -
This circuit was designed as a warning flasher to alert road users to dangerous situations in the dark. Alternatively, it can act as a bicycle light (subject to traffic regulations and legislation). White LEDs only are recommended if the circuit is used as a.... -
Hello, I need a simple to make LED based (not 7-segment) voltmeter to monitor the voltage of a variable supply. I have found this circuit.... -
New design techniques in LED driver circuits promise to deliver significant energy savings that will go a long way toward helping TV manufacturers meet the tough requirements for power consumption.... -
To create the circuit you will need to connect a switch as an input and an LED as an output to the Arduino. This means that you will need a switch, an LED, a 10k © resistor, a 470 © resistor, a blue or yellow jumper wire, and a red jumper wire. The Arduino.... -
Using MAX1496 an ADC with LED drivers, you can make your own 3 1/2 digit voltmeter with just a handful of components. It even has external/internal Vref, HOLD and PEAK as well as 200mV, 2V rangs.... -
The bi-directional sequencer uses a 4 bit binary up/down counter (CD4516) and two “1 of 8 line decoders“74HC138 or 74HCT138) to generate the popular Nigh.... -
This circuit is designed to drive the 1W LEDs that are now commonly available. Their non-linear voltage to current relationship and variation in forward v.... -
If you`ve ever tried dimming a LED with a simple potentiometer, you know that the approach does not work very well. Just as with ordinary diodes, the voltage-current characteristic of LEDs is far from linear. The result depending on the potentiometer setting.... -
This simple LED tester consists of a current source with a potentiometer that can be used to adjust the current. The current source is implemented using a type TL081 opamp. The output current of the opamp flows through the diode and R2. The voltage drop.... -
Without any dedicated buck converter/white LED driver IC, you can safely drive many standard Hi-efficient white LED modules using the battery power available in automobiles. Here is a safe and simple white LED driver designed for 12V automobiles. In the.... -
A useful timing strobe can be constructed using high-brightness LEDs and a few common components. Ignition pulses from the number 1 cylinder high-tension lead are used to trigger the circuit via a home-made inductive pickup. Transistors Q1 & Q2 buffer and.... -
This circuit was designed as a warning flasher to alert road users to dangerous situations in the dark. Alternatively, it can act as a bicycle light (subj.... -
First I bought another front wheel, one which has a dynamo already built in the hub. This supplied a nice sine wave of 30 Vpp (at no load). With this knowledge I designed a simple power supply. The transistors that are used are type BD911. These are a bit of.... -
The idea behind this economical ?ashing LED indicator is very simple: it uses a very low frequency oscillator to drive two LEDs. As can be seen in the cir.... -
The consumer unit (or electricity meter`) cupboard in some older houses is a badly lit place. If the bell transformer is also located in this cupboard, it may be used to provide emergency lighting by two high-current LEDs. These diodes are powered via a.... -
Ideal to operate 3 to 24V DC existing on-circuit lamps This circuit was designed to provide that continuous light lamps already wired into a circuit, beco.... -
Common to all the devices is that they emit intense red light with a wavelength of 660 nm. Some biophysicists claim that light of this wavelength can have a positive effect on the human body and can initiate healing processes. This so-called phototherapy` is.... -
Before you use LEDs, it`s a good idea to check them out. With a LED tester, you can even do it in the dark! LEDs are available nowadays in all shapes and colors. There are types with clear, colorless packages, while others have colored plastic packages. Many.... -
This simple LED torch is driven by a 2-transistor blocking oscillator which steps up the voltage from a 1.5V cell. It relies on the inherent current limit.... -
Small in size! Big in use Here is a simple and powerful LED circuit that can be operated directly from the AC 100 volt to AC 230 Volts mains supply. The c.... -
Did it ever occur to you that an array of white LEDs can be used as a small lamp for the living room? If not, read on. LED lamps are available ready-made,.... -
Most PC enclosures provide only a single LED to indicate hard disk access, with the LED being connected to the motherboard via a two-pin connector. However, this LED only works with IDE drives, and if a SCSI disk controller is fitted, its activity will not.... -
Although this design is reproduced directly from the manufacturer s datasheets, its use in this application is rather novel. Originally intended for high-.... -
You can save on your electricity bills by switching to alternative sources of power. The photovoltaic module or solar panel described here is capable of d.... -
This ultra-bright white LED lamp works on 230V AC with minimal power consumption. It can be used to illuminate VU meters, SWR meters, etc. Ultra-bright LE....
New Circuits
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This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of.... -
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is.... -
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to.... -
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This.... -
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the.... -
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,.... -
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the.... -
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power.... -
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
Popular Circuits
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