Showing posts with label led. Show all posts
Showing posts with label led. Show all posts
Thursday, November 13, 2014
LED Sound level display circuit by using IC LM3915
This circuit is about audio sound level LED display, indicator, monitor or you can say it “Audio VU (Volume Unite) Meter”.
This is a simple audio sound level LED display circuit diagram. The circuit is completely based on a single ic LM3915 from National Semiconductor. The LM3915 is a monolithic integrated circuit. It displays the audio sound level in terms of 10 LEDs and providing a logarithmic 3 dB/step analog display.
This is a simple audio sound level LED display circuit diagram. The circuit is completely based on a single ic LM3915 from National Semiconductor. The LM3915 is a monolithic integrated circuit. It displays the audio sound level in terms of 10 LEDs and providing a logarithmic 3 dB/step analog display.
Audio sound level display circuit diagram
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| Fig: Circuit diagram of sound level display using ic LM3915 |
The audio sound level LED display circuit can operate from a single supply 3V to 25V. But I suggest to use 9-12V. LED brightness can be controlled with a single pot( variable resistor) as shown 10K ohm in the circuit. Connect the audio input signal in Pin-5 of LM3915 from output of a audio device like output of audio amplifier or any other source.
The Pin-9 of LM3915 is to select dot or bar mode display. To make the circuit moving dot display instead of a bar graph display disconnect the Pin-9 from +V. 
Tuesday, November 11, 2014
LED flasher with Transistor circuits Diagram
These circuits only flash one or two LEDs. This is opposed to the light chaser circuits that can flash four or more. Of course, the simplest LED flasher is simply to use a flashing LED. The problem with that approach is you have no control over the flash rate, but it does have its use for eye catching displays for selling stuff. The circuits below give you that control, plus they can flash two LEDs alternately.
There are many possible applications for the circuits below, especially for kids, who love flashing lights. Heres some possible uses.
- Railroad crossing signal for model railroads.
- Safety blinkers for bicycles, etc.
- Fun stuff for Halloween, like making those plastic Jack-O-lanterns blink (try using ultraviolet LEDs here).
- Christmas decorations.
- Blinkers to locate items in the dark.
Transistor LED flasher
This circuit has a lot going for it. For one thing, it only consists of two transistors, two capacitors and four resistors. That also means it consumes very little power. You can control the flash rate by changing the size of the 100k resistors (100k makes for a pretty slow rate). You can also control the duty cycle by using resistors of different values on the two sides. The 470 ohm resistors control the current through the LEDs. Normally you want to limit this to 20mA, but to conserve battery power, you may need to limit it even further. You can also connect several LEDs in series, instead of using only one for each side. With red LEDs (1 per side) and the values shown, the circuit draws about 11mA. Heres what the actual circuit looks like:
On this circuit, the green wires connect to the LEDs, but you can mount them on the actual circuit board for some applications. The picture is about twice actual size.
Thursday, November 6, 2014
8 Stage LED VU Meter
The circuit below uses two quad voltage comparators (LM339) to illuminate a series of 8 LEDs indicating volume level. Each of the 8 comparators is biased at increasing voltages set by the voltage divider so that the lower right LED comes on first when the input is about 400 millivolts or about 22 milliwatts peak in an 8 ohm system.
8 Stage LED VU Meter Circuit diagram :
The divider voltages are set so that each LED represents about twice the power level as the one before so the scale extends from 22 milliwatts to about 2.5 watts when all LEDs are lit. The sensitivity can be decreased with the input control to read higher levels. I have not built or tested this circuit, so please let me know if you have problems getting it working. The power levels should be as follows:
- 1 LED = 22mW
- 2 LEDs = 42mW
- 3 LEDs = 90mW
- 4 LEDs = 175mW
- 5 LEDs = 320mW
- 6 LEDs = 650mW
- 7 LEDs = 1.2 Watts
- 8 LEDs = 2.5 watts
Monday, November 3, 2014
CHALLENGES DESIGN OF SWITCHING LED ELECTRONIC DIAGRAM
CHALLENGES DESIGN OF SWITCHING LED ELECTRONIC DIAGRAM
The LED WEBENCH® online design environment predicts and simulates the response of an LED to constant current while taking into account several potential design parameters that are new to designers of traditional switching regulators.
Tuesday, October 28, 2014
Two Colour LED Light Bar Circuit
This circuit is a circuit run on alternating two insignia.It uses the 2-color LED with a built-participating in 3-pin single.This preference look for away the glow of every LED until the base.It turns alternating to one more color.In in the least way to the moon on the moon essential end, afterward the LED end of the first LED.Circuit consists of, nand gate ic.Two 10 Counter circuits IC, and IC JK flip washout.
company of the circuit is not speaking into 3 sets.It is a solid of gesture generators, a set of parade and control.Set the signal generator is IC1a,and IC1b quantity 4011 is a signal generator.The R2, R3, C2 determine the frequency generated.The hint is fed to a set of impressions is the figure 4011 IC2 and IC3.The 10 counter circuits to output to the LED, and Is the same, but the effort should ensue performed individual by the side of region. Therefore, the show from pin 11 of IC 2 and tested pro D2 and D3,To pin 3 of IC4.The integrated circuit IC 4 is a JK flip slump is connected to a T flip flop.The signal input pin 3 and pin 1 is the output hint at.Which sends a signal to the Reset IC either obstruct working.IC4 on the anniversary, it want output the originally moment in time, happening contrast to pin1.IC3 progress to handiwork, IC2 stopped.
IC2 is controlled by signals from pin 1 of IC4, to IC1c.earlier to control IC2.The IC3 is connected to pins 1 through D1 to the control again.
Sunday, October 26, 2014
LED Lights circuits with LM339 IC555
This circuit reproduces the opening light sequence now used by FISA instead of Formula individual racing. It may possibly befall used with slot car sets (such like HO shin up AFX/Life Like/Tyco sets) or else means of communication controlled cars. IC1, a 555 timer IC, is used as a meter pulse generator. Its output is fed via NAND gates IC2a and IC2c to IC3, a 4024 binary counter. IC2b inverts the O4 output of 4024 binary counter IC3. at first, IC3 is reset and all its outputs are low, together with O4, which causes IC2b to grant a commonsensical climax to the pin 8 input of IC2c which afterward passes pulses from the 555 timepiece circuit to the clock input of the 4024. IC3 then begins including.
Similar to the count has reached binary 1111, the then pulse sends the O4 output of IC3 high, which disables IC2c and IC3 stops together with. The four used outputs of IC3 are connected to a resistor ‘ladder’ which acts because a undemanding digital to analog convert-er (DAC). As the count increases so does the voltage produced by the top of the ladder and this is connected to the inverting inputs of four comparators inside IC4 (an LM339) and to IC5, which is a 741 op amp besides connected for instance a comparator.
The certain inputs of the comparators are connected to the taps of a voltage barrier, with the drumming voltages frozen using VR1, a 100kO trimpot. As IC3 counts, the rising stepped voltage from the DAC ladder switches the comparators on during sequence, preparatory with IC4d and working up to IC5. because each one comparator is bowed on, its put together of LEDs is lit; essential LEDs 1 & 2, so therefore LEDs 3 & 4 and so on. at what time all five pairs of LEDs are lit, the after that pulse from IC1 moves the binary count of IC3 to 10000, so the DAC voltage drops back to zip and all LEDs are extinguished. by the same age, plus additionally stops, as the lofty on O4 causes IC2c to mass expand gate pulses. The circuit it follows that remains stationary until the counter is reset by burning pushbutton switch S1. This allows a new-fangled sequence to kick off.
Similar to the count has reached binary 1111, the then pulse sends the O4 output of IC3 high, which disables IC2c and IC3 stops together with. The four used outputs of IC3 are connected to a resistor ‘ladder’ which acts because a undemanding digital to analog convert-er (DAC). As the count increases so does the voltage produced by the top of the ladder and this is connected to the inverting inputs of four comparators inside IC4 (an LM339) and to IC5, which is a 741 op amp besides connected for instance a comparator.
The certain inputs of the comparators are connected to the taps of a voltage barrier, with the drumming voltages frozen using VR1, a 100kO trimpot. As IC3 counts, the rising stepped voltage from the DAC ladder switches the comparators on during sequence, preparatory with IC4d and working up to IC5. because each one comparator is bowed on, its put together of LEDs is lit; essential LEDs 1 & 2, so therefore LEDs 3 & 4 and so on. at what time all five pairs of LEDs are lit, the after that pulse from IC1 moves the binary count of IC3 to 10000, so the DAC voltage drops back to zip and all LEDs are extinguished. by the same age, plus additionally stops, as the lofty on O4 causes IC2c to mass expand gate pulses. The circuit it follows that remains stationary until the counter is reset by burning pushbutton switch S1. This allows a new-fangled sequence to kick off.
Wednesday, September 17, 2014
Night Rider 16 Stage Bi Directional LED Sequencer circuit
This bi-directional LED sequencer schema uses IC CD4516 and IC 74HCT138 as counter and decoder.
Circuit explanation:
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 "Night Rider" display. A Schmitt Trigger oscillator provides the clock signal for the counter and the rate can be adjusted with the 500K pot. Two additional Schmitt Trigger inverters are used as a SET/RESET latch to control the counting direction (up or down). Be sure to use the 74HC14 and not the 74HCT14, the 74HCT14 may not work due to the low TTL input trigger level. When the highest count is reached (1111) the low output at pin 7 sets the latch so that the UP/DOWN input to the counter goes low and causes the counter to begin decrementing. When the lowest count is reached (0000) the latch is reset (high) so that the counter will begin incrementing on the next rising clock edge. The three lowest counter bits (Q0, Q1, Q2) are connected to both decoders in parallel and the highest bit Q3 is used to select the appropriate decoder.
source: http://www.qsl.net/yo5ofh/hobby%20diagram/led_diagram.htm
Read More..
Circuit explanation:
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 "Night Rider" display. A Schmitt Trigger oscillator provides the clock signal for the counter and the rate can be adjusted with the 500K pot. Two additional Schmitt Trigger inverters are used as a SET/RESET latch to control the counting direction (up or down). Be sure to use the 74HC14 and not the 74HCT14, the 74HCT14 may not work due to the low TTL input trigger level. When the highest count is reached (1111) the low output at pin 7 sets the latch so that the UP/DOWN input to the counter goes low and causes the counter to begin decrementing. When the lowest count is reached (0000) the latch is reset (high) so that the counter will begin incrementing on the next rising clock edge. The three lowest counter bits (Q0, Q1, Q2) are connected to both decoders in parallel and the highest bit Q3 is used to select the appropriate decoder.
source: http://www.qsl.net/yo5ofh/hobby%20diagram/led_diagram.htm
Thursday, September 11, 2014
Simple LED Torch
A common problem with small torches is the short life-span both of the batteries and the bulb. The average incandescent torch, for instance, consumes around 2 Watts. The LED Torch in Fig. 1 consumes just 24 mW, giving it more than 80 times longer service from 4 AA alkaline batteries (that is, up to one months continuous service). Although the torchs light output is modest, it is nonetheless quite sufficient to illuminate a pathway for walking.
Circuit Diagram :
Fig. 1 : Simple LED Torch Circuit Diagram
The LED Torch is based on a 7555 timer running in astable mode (do not use an ordinary 555). A white LED (Maplin order code NR73) produces 400 mcd light output, which, when focussed, can illuminate objects at 30 metres. Try Conrad Electronic for what appears to be a stronger white LED (order code 15 37 45-11). A convex lens with short focal length is placed in front of the LED to focus the beam. If banding occurs at the beams perimeter, use another very short focal length lens directly in front of the LED to smooth the beam.
If a different supply voltage is preferred, the value of resistor R3 is modified as follows:
9V - 470 Ohm12V - 560 Ohm
See my "Wind-up Torch" feature article in the October 2000 edition of Everyday Practical Electronics for a completely battery-free go-everywhere torch.
Thursday, September 4, 2014
How to Reuse Old Cell Battery for LED lighting
Normally cell batteries have a shelf life of 2 to 5 years under normal use. After that time we have to replace them. Nowadays there replacement batteries which are cheap, but these batteries last for much less cost only months. An easy solution is to use batteries in a schema that requires less current, we can use them for lighting LEDs.
How to Reuse Old Cell Battery for LED lighting
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How to Reuse Old Cell Battery for LED lighting
Wednesday, August 27, 2014
Simple LM3410 LED Driver
The LM3410 IC is a constant current LED driver useful in either boost con-verter or SEPIC design applications. A SEPIC (Single Ended Primary Induct-ance Conver ter) design allows the power supply’s output voltage to be set above, below or equal to its input voltage. In this application the chip is configured as a boost-converter (i.e. the output voltage is greater than the input voltage).
LM3410 LED Driver Circuit Diagram
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The LM3410 is available in two fixed-frequency variants. Using either the 525 kHz or 1.6 MHz clock version it is possi-ble to build a ver y compact LED driver. The output stage can supply up to 2.8 A, allowing several high-power LEDs to be driven from a rechargeable Lithium cell or several 1.5 V bat-teries. The chip also features a dimmer input giving simple PWM brightness control.Output current is defined by an external shunt resistor. To keep losses low the LM3410 uses an internal voltage reference of just 190 mV.
Power dissipation in the shunt resistor is therefore low. Using the desired value of LED current the value and power dissipation of the shunt resistor is given by:
R_Shunt = 0.19 V/I_LED
P_Shunt = 0.19 V*I_LED
A 10 µH coil (L1) will be suf ficient for most applications providing it has a suitable satu-ration current rating. The Input and output capacitors should be 10 µF ceramic t ypes with a low value of E SR . Many distributor s including Farnell stock these component s. The Diode should beaSchottky type (as in all switching regulators). The author has developed a PCB for this design; the corresponding Eagle files can be freely downloaded from www.elektor.com/090850. In sum-mar y the most important features of the LM3410 are:
- Integrated 2.8 A MOSFET driver.
- Input voltage range from 2.7 V to 5.5 V.
- Capability to drive up to six series connected LEDs (maximum output 24 V).
- Up to 88 % efficiency.
- Available is 525 kHz and 1.6 MHz versions.
- Allows both boost and SEPIC designs.
- Available in 5 pin SOT23 or 6 pin LLP outline.
230V Blinking LED
Already I have posted 230V LED schema diagrams.This schema is different than those diagram.Because this schema is blinking schema.And here I have used common parts so you all can find them easily.Already I have attached this schema with our doorbell switch then the visitors who visit my place at night can see it well.
Note:-
# When you deal with 230V be careful because it is dangerous
# Fix this schema in a plastic box
Monday, August 25, 2014
High intensity LED Warning Flasher Wiring diagram Schematic
This schema 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 schema is used as a bicycle front light (i.e. for road illumination) and red LEDs only when used as a tail light. During the day, the two 1.6-V solar cells charge the two AA batteries. In darkness, the solar cell voltage disappears and the batteries automatically power the schema.
High-intensity LED Warning Flasher Circuit Diagram
The flash frequency is about one per second and the LED on-time is about 330 ms. The duty cycle should enable the batteries to power the schema over night. The schema is composed of three parts. Under normal daylight conditions the batteries are charged through diode D4. In darkness, pnp transistor T1 is switched on, supplying battery current to the second part, a low-frequency oscillator comprising T2 and T3.The third part is the LED driver around T4.
It conducts and switches on the LEDs D1-D2-D3 when the collector voltage of T3 swings high. Two LEDs (D1, D2) are 20,000-30,000 mcd high-brightness yellow types and one (D3) is a normal 3-mm red LED for control purposes. Of course it is possible to increase the number of LEDs to obtain higher brightness. However you will run into limitations regarding the maximum collector current of transistor T4. For really high power applications a MOSFET transistor is suggested instead of the common or garden BC547B.
Author: Jose Luis Basterra - Copyright: Elektor
Friday, August 15, 2014
Using LED as a diode Rectifier Wiring diagram Schematic
This is a simple LED as a diode Rectifier Circuit Diagram. In certain situations where the current is not high, we can use the famous LED (LED) and diode rectifier voltage power diagram. The LED can be used without problem in a rectification schema, and also works in the power ratings. Pay attention not to exceed the maximum current of the LED in a wave rectifier.
Using LED as a diode Rectifier Circuit Diagram
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