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Light Laser LED Circuits
Universal High-Power LED Driver with 3D-printable Case
The heart of this controller is a switch mode voltage converter. L1 converts voltage. Q1 is the switch that control current the goes through L1. The b..
High-intensity LED Warning Flasher
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 bicycle front light (i. e. for road illumination) and red LEDs only when used as a tail lig
LED Phototherapy Unit
It is widely thought that light can be therapeutic for the human skin and soul. Light at the correct wavelength may also be effective against depression and allergies. There is a wide range of products on the market, at prices from a few tens of pounds to a hundred pounds or so, which are presented as universal remedies for dust allergies or hay f
Multicolor HD LED
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 be visibly noticeable. This small circuit remedies that problem using a multicolour LED. The
Thrifty LED Protector
An LED is sure to fail if the current through it is too high. You will soon discover this after you have blown a few up. A simple resistor in series suffices to solve the problem and a better solution is almost inconceivable, because in this case you need only one additional cheap component. As the power supply voltage increases, an increasing amo
How to Apply Additional PWM Intensity Control to LED Drivers
Different techniques show how additional PWM (pulse-width modulation) intensity control can be applied to LED (light-emitting diode) drivers..
pulse generator circuit
With the relaxation oscillator, we basically achieved a fairly regular square wave. Let's change the duty cycle (and visualize the effect with LEDs). Wire up the following variation on the relaxation oscillator circuit
led driving techniques reduce power in lcd tvs
LED display unit
For a couple of recent projects we have been asked to provide interesting and informative display units. We decided to build a unit which can be used in a number of different applications. It was designed to look good, be able to show graphics and text, have a couple of switch inputs and be configurable for a variety of uses. The end result was so
Programmable LED Flashers
Delay Circuit With Indicator LED
Wide Input-Voltage Range High-Power LED Driver
This is a wide input-voltage range high-power LED driver circuit. This circuit based on a buck/boost converter controller regulates current to a white LED..
Manual Adjustable LED Driver
In many electronics-level adjustments such as LED drivers for LCD panel backlight controls, we can use AD5228. A manually adjustable LED driver is shown on..
Sound Controlled Activated Triggered LED
When the microphone detects a loud sound, this circuit will turn the LED on. The `charge-pump` section consists of the 100n, 10k, signal diode and uF..
LED message display schematic
RGB LED Love Heart
This project creates a RGB LED lit love heart which is controlled by a PIC12F683 microcontroller. I designed the project as a gift for my wife on our 15th wedding anniversary (since she puts up with my addiction to electronics I thought she deserved something in return!). The love heart is made from a 200x150x6mm sheet of plexi-glass which is cut
Constant Current LED Drive
However, for applications needing many LEDs, this becomes extravagantly inefficient and it is tempting to keep the voltage drop across the resistor as small as possible. That leads to poor control of the current. ICs such as the MM5450 and its relatives and the A6275 and its relatives provide constant current outputs so that the current through...
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 circuit diagram, the LEDs are connected in anti-parallel. At every change in level there will only be a current ¬‚ow for a short time, due to the large capacitor (C3) that is connected in series
LED Dance Pad
Using LEDs as light sensors. A DDR pad. We designed our pad to have no moving parts. Instead, we chose to measure light reflectance off the user`s feet to determine if one of the arrows was being stepped on or not. Since a design with no moving parts offers little to no tactile feedback, we wanted to make sure the pad offered some other form of...
Light Sensing Circuits
Light Dimmer Circuits
Ultrasonic distance finder circuit
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 measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
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 find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
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 circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
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 circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
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, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
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 calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
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 supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
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. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
Digital Signal Integrity
Interconnection and Timing of Digital Circuits
CMOS Circuits Tutorial