LED Circuits
-
Construction LED circuit shown in Figure. It requires manual power, after the circuit is powered, the light will blink to remind people to pay attention to safety. .. -
Explanation The circuit is nothing more than two light emitting diodes (D1 and D2), its position is controlled by the temperature of the surrounding environment. Here the tempe.. -
Driving series white LED, flowing through the same song in each white LED current, it is possible to obtain a uniform brightness. The disadvantage of the tandem drive is the dr.. -
Drive the light emitting diode is shown in the digital display circuit, the count signal to ICM7217 feet in the chip by the count and after the coding process to drive the digi.. -
Configure National Semiconductors DS8877 drive circuit as shown, when the 6 digit calculator and digital current conjunction, the current range is 5 to 50mA. Drive does not req.. -
The circuit will modulate the light from the LED using a crystal microphone or a loudspeaker output. To obtain the maximum range, the optical system must be efficient (see example). Either a convex lens or a concave mirror can be used to convert the LED.... -
Have you ever wondered how many different colors can illuminate a LED? One, two or maybe three? Constructing this simple circuit, you will find it much more. The key component in this design is a dual LED. One such accessory includes two inside the 'slices'.... -
Indicator was designed for displaying the peak level of small ac signals from a variety of transducers including microphones, strain gauges and photodiodes. The circuit responds to input signals contained within the audio frequency spectrum, i.e., 30 Hz to.... -
The circuit uses CA3290 BiMOS dual voltage comparators. Non-inverting inputs of A1 and A2 are tied to voltage divider reference. The input signal is applied to the inverting inputs. .. -
When SI is on, power is applied to an oscillator composed of Ql, Rl, Cl, LI, and L2. Coil Ll is the primary winding of Tl, and L2 is the feedback winding. When Ql turns on, its collector current saturates Tl's ferrite core. That, in turn, removes the base.... -
A 741 op amp is employed as a voltage comparator. The noninverting input is connected to zener reference source. Reference voltage is 5V. R2 is adjusted so that the voltage at the inverting input is half the supply voltage. When supply is higher than 10V,.... -
The precision voltage-monitor chip contains a temperature-compensated voltage reference. R1 divides down the battery voltage to match the built-in reference voltage of ICl (15 volts). When the voltage at pin 3 falls below 15 volts, pin 4 supplies a constant.... -
A simple level of power meter can be arranged to give a bar or dot display for a hi-fi system. Use green LEDs for 0 to 7; yellow for 8 and red for 9 to indicate peak power. The gain control is provided to enable calibration on the equipment with which the.... -
Use a pair of Maxim"s 5V-powered MAX231 RS-232C transmitters as drivers to obtain a 2-color LED. The transmitters require only a singleended, 5-V input to generate ± 10 V internally. Their outputs are short-circuit-proof and can supply as much as 10.... -
The pull-up transistor of the totem-pole output is used-to turn on the LED and the pull-down transistor is used to turn ·off the LED. The lower impedance and higher current handling capability of the saturated pull-down transistor is used as an effective.... -
When power is first turned on, two of the LEDs are on and the other two remain off until the timing cycle reverses. The LEDs flash in pairs, but by pressing and holding Sl closed until only one of the LEDs is on, and then releasing it, the four LEDs can be.... -
Inserting two 1-MO resistors, R1 and R2, in the output stage of one of the circuit"s inverters limits the current needed by the oscillator tone more than a few pA. This circuit includes a CD4007 package, which has three CMOS inverters. It forms a standard.... -
The timing components are Rl, R2, and C,. Cl is a bypass capacitor used to reduce the effects of noise. At start-up, the voltage across C, is less than the trigger level voltage (1/3 Vnn). causing the timer to be triggered via pin 2. The output of the.... -
Uses a low cost CMOS IC to tum four LEDs on and off at a rate that is set by the values of R1, R2, Cl, and C2. The pulse rate for the component values given for R1 and R2 is about one cycle every four seconds. By lowering the values of Rl and R2 to 220 KO,.... -
This indicator is basically a switch with hysteresis characteristics. If the input voltage momentarily (or permanently) exceeds the most positive reference level, LEDl is switched on. If, on the other hand, the voltage falls below the negative, or least.... -
The ·circuit includes a peak detector that irrunediately drives the readout to any new higher signal level and slowly lowers it after the signal drops to zero. The readout is a moving dot or expanding bar display. The circuit can be expanded for a longer.... -
The LED with integrated flasher is connected in series with the base-emitter junction of transistor Tl. Thus, the l.. -
Many electronic circuits need an indication that they are under power; for most ac circuits, a neon lamp is .. -
When the mains voltage is present at the input terminals, the transistor in the optocoupler is on, T1 is off, and s.. -
Battery-operated equipment can work on one set of batteries for a long time nowadays. However, if it is left on inadvertently,.. -
The super LED flasher is actually two complete LED flasher circuits on one circuit board. The first, LED flasher is made up of 1C1 and LEDs D1 and D2. IC1 is a 555 timer IC configured as an astable (free-running) multivibrator with its output on pin 3. The.... -
Three individual flashing circuits that use an LM3909 LED flasher/oscillator IC create the appearance of a pseudo-random firing order. The combination of CX!RV C.JRb, and C^R control the blink rate, which is between 0.3 and 0.8 s, and the inherent wide.... -
A bar column of LEDs is arranged so that as the audio signal level increases, more LEDs in the column light up. The LEDs are arranged vertically in 6 dB steps. A fast response time and a one second decay time give an accurate response to transients and a low.... -
A relaxation oscillator is used to flash an LED in the base circuit. Cl is charged slowly through R1 by the power source, then discharged periodically through R3 and the LED by the UJT. .. -
The LED is the CSL310L which contains a red LED and a green LED connected back to back and mounted close together in a single moulding. The LED can emit red or^green light by controlling the polarity of the applied voltage and if the polarity is switched at.... -
This electronic level uses two LED indicators instead of an air bubble. If the surface is tilted to the right, one LED lights; if it's tilted to the left, the other LED lights. When the surface is level, both LEDs light. It uses two unidirectional mercury.... -
This screen uses ten LEDs to display a voltage range of 10.5 to 15 volts. Each LED represents a step 0.5wvolt tension. The heart of the circuit is the 3914 points LM / bar display driver. Trimming potentiometer R5 is adjusted so that 7.5 volts is applied to....
New Circuits
-
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
This circuit controls a load (in this case a dc brushless fan) based on a temperature compared...
A long time ago when telephones were so simple almost nothing could go amiss from an electrical...
The following data and mapping are for the 2-D shift mapping algorithm that the controller will...
Amplifier device that accepts a varying input signal and produces an output signal that varies in...
This is a simple single-zone burglar alarm circuit. Its features include automatic Exit and Entry...
All feature crystal-controlled transmitters and tunable superregenerative receivers with RF...
A cellular rotary phone - the dialing takes forever! And here in Colorado - on a 10-digit dialing...