LED Circuits
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Is possible to syncronize the leds so that first, the speakers are still playing aloud, and two, the led are not always on during music playing. i pretty educated in electrical so i hope there is anyway at all to do this. Thanks. I`m having trouble following.... -
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.... -
Hi This is a 25 nos Led operated from mains of 230v supply. I bought a flourscent lamp adapter from a scrap dealer, because its easy to disman.... -
A new spin on a great kit. Have you ever seen the dot-matrix displays that can display letters, numbers, or even icons Once you know the basics for how to display something on one matrix, you can daisy-chain the Maxim Max7219 ICs and LED matrices to display.... -
You will need 512 properly working LEDs in the lattice. They will need to be stable and bright. This step will show you how to separate the faulty ones from the usable ones. Lots of times there are broken LEDs, especially when they come in large packages..... -
The JarLight is a small flashlight based on a white light emitting diode (LED). It is powered by a single battery cell. This combination enables a very compact case at a very high light power and long-life. Not only of the battery but also of the LED. To.... -
Common Light Emitting Diodes (LEDs) require a DC forward bias current of 10 to 20 mA for proper operation. Typically the maximum DC current is 30 to 50 mA. The color of light (or wavelength ») emitted from an LED depends on the semiconductor material used to.... -
The speed of light has been measured many different ways using many ingenious methods. The following note describes a method which is conceptually easy to understand and fairly easy to implement. The technique is the simple time-of-flight optical pulse delay.... -
Easy build and use, the general purpose Big LED with SPI serial interfacing. Expandable for multiple digits but still uses only three wires for receiving data from any uC boards. The circuit uses a serial-in-parallel out shift register, 74HC595 for receiving.... -
For this project, we are going to charge a capacitor with voltage and then have the capacitor act as a temporary power source for the circuit. After we charge the capacitor with the battery, we`re going to disconnect the battery from the circuit. The.... -
The 555 timer chip is a very versatile IC, because when connected correctly, it can it can create pulses of current at specific time intervals decided by the resistor-capacitor (RC) network. When a 555 timer creates pulses in this way, the LED doesn`t stay.... -
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 voltage with temperature necessitates the use of a 350mA, constant-current power source as provided by.... -
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.... -
Most LED driver circuits use a series resistor to control the current through the LED. For applications needing a few LEDs, this is optimal. However, for applications needing many LEDs, this becomes extravagantly inefficient and it is tempting to keep the.... -
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.... -
The simple indicator presented in this article may be combined, in principle, with any circuit that contains an LED bar display driven by a Type LM3914 IC. It ensures that an LED will light when all LEDs driven by the LM3914 are out. This prevents one.... -
Physicians and repair engineers often use small light pens for visual examination Spurposes. Rugged and expensive as these pens may be, their weak point is the bulb, which is a serviceable` part. In practice, that nearly always equates to expensive` and / or.... -
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.... -
You have to admit that these tiny electronic lamps are handy, and they last almost forever. Around 40 years after Nick Holanyak developed the first LED, they have become just about indispensable. Any self-respecting electronics hobbyist always has a few in.... -
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 limiting of the 150 µH choke to protect the white LED from over-drive. With a 9V zener diode in place of the.... -
Here is a Simple LED Volt meter to Monitor the charge level in Lead Acid Battery or Tubular battery. The terminal voltage of the battery is indicated through a four level LED indicators. The nominal terminal voltage of a Lead Acid battery is 13. 8 volts and.... -
How many different conditions do you reckon may be signalled with just one LED Two, maybe three Using this simple circuit, a lot more! Admittedly, a two-colour LED is used here. Such a device consists of two light-emitting chips, usually red and green,.... -
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-visibility LED bargraph readouts, here the LM3914 is used as the basis of a 10-step variable brightness.... -
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 delivering a power of 5 watts. At full sunlight, the solar panel outputs 16. 5V. It can deliver a current.... -
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.... -
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 LEDs available in the market cost Rs 8 to 15. These LEDs emit a 1000-6000mCd bright white light like.... -
This circuit uses low-voltage AC to drive a string of 50 or so bi-color LEDs (two LEDs connected in inverse parallel). Power to the LEDs is controlled by the Triac and the two optocouplers which have their photo-transistors effectively connected in.... -
This circuit shows how to use an ordinary LED as a light sensor. It makes use of the photovoltaic voltage developed across the LED when it is exposed to light. LEDs are cheaper than photodiodes and come with a built-in filter, which is useful when the.... -
The model 4017 integrated circuit is a CMOS counter with ten output terminals. One of these ten terminals will be in a "high" state at any given time, with all others being "low, " giving a "one-of-ten" output sequence. If low-to-high voltage pulses are.... -
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.....
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