Four LM3914 VU Meter circuits

I make a lot of amplifiers. Because I like to listen to music. And a VU Meter circuit is a circuit that I like it. In addition, it is used to display the power level of the audio, it also is beautiful.

Many friends, would prefer same me. When you go to the electronic equipment store to buy the VU meter kit, with the assembly various parts on their own or the style ready to use. Most of us are using the IC-LM3914, because it is convenient, easy to modify in many form. Today I assemble a the circuits that use this IC. Sometimes you are looking for ideas on this. For example: Flashing lights by the band, to decorate the Christmas tree, exotic, and unique.

Note: Here is the LM3914/LM3915 VU meter projects

VU meter 10 LED using LM3914

VU meter circuit is an IC number LM3914. This is a circuit that is commonly used standards. Within the integrated circuit LM3914 is a voltage range advantage. This is the fourth leg split. Reference voltage pin 6 is low, and the reference voltage divided up.
When raising the power supply circuit and the signal came, the sound signal to be via D1 Optical Direct Fire only split the signal to positive The C1 and R1 signal smoothing filter. Then, light is sent through R2 to access the input pin 5 of IC by the IC to the display of the signal starts from the output pin 1 or LED1 contiguous to the leg 10 or LED10. You can choose form of a display 2. is a bar display and the display. Select use the switch S1. VR1 which acts on the set voltage reference ICs and R3 of the output current limiting function. If the value at which R3 LED1-LED10 are very bright.

Note: Here is Features of LM3914
-Drives LEDs, LCDs or vacuum fluorescents
-Bar or dot display mode externally selectable by user
-Expandable to displays of 100 steps
-Internal voltage reference from 1.2V to 12V
-Operates with single supply of less than 3V
-Inputs operate down to ground
-Output current programmable from 2 mA to 30 mA
-No multiplex switching or interaction between outputs
-Input withstands 35V without damage or false outputs
-LED driver outputs are current regulated, open-collectors
-Outputs can interface with TTL or CMOS logic
-The internal 10-step divider is floating and can be referenced to a wide range of voltages

LED VU Meter by IC LM3914

This is Circuit LM3914 LED VU Meter. use IC1-LM3914 and Transistor BC109C, By circuit will show level of audio signal(power Music) is “dB” in six level by LED display or also known as VU-METER. for the stereo system. In this : VU meter 10 LED using LM3914 is basic it can monitor 10 led but use for high signal, when we add the Q1-BC109 at input section to boost up current for low level signal input. As you see,Be mono circuit but if you would to need stereo,you are going to make only other one. It is Build easily because use the integrated circuit just one and the price is inexpensive. The detail is all , see in the circuit better.

Led light based music circuit with LM3914

This is a simple light running circuit by music This circuit is not difficult, is MONO, with a few accessories. Can be connected to the output of a CD or cassette player Time.
Operation of the circuit. Begins to be input via VR. The VR will function fine, signal strength coming. D1 will take disconnected hemisphere plus leaving only the signal hemisphere removed to activation of Q1. Signal is extended through Q1 to pin 5 input of IC1. By C1 forward delay of the IC is not the LED (connected to the output. of IC1) off immediately. The IC IC1 is finished. The act shows the effect of the voltage at IC1 pin 5 of the display by the LED to pins 1-19 of the IC, which is within range. compared to a multiple voltage standard circuits. The circuit can operate effectively. In the R1 that it will determine the current flowing through the LED. To prevent LED damage.
Use should be connected to the input of the circuit. To the speaker terminals, change the value of R3 is 10k and IC1 can choose to display two types Bar (Bar) when the pin 9 and a power source. Dots (Dot) on 9-pin to float to drop.

Led light based music circuit with LM3914

Led light based music stereo with multi system

This circuit is another name for the VU meter. which often have a lot of equipment. Cause problems for people who start training. But this cycle is not much equipment. You can also choose, in the.
Running a bar or run with a point.
Operation of the circuit. It is the primary device IC number LM3914N is ready to show the effects of pressure, as a bar or have a point. Behavior of IC1 and IC2 is similar circuit R2, R3, VR1 is connected in the manner divided voltage to the input to the voltage appropriate, through D1 to Pin 5. by R1 and C1 are waiting delay. Input pin 5 not to fade away soon.When a signal to the output of each IC pin is connected to the 3-Series LED, to limit the flow. But if you want the LED on the moon alone would have to go with the R series. The S1, S2 are optional format of the display LED.

Led light based music stereo with multi system

Note: Do not forget to take a look the VU meter kit on the
May be more expensive than buying the general store. But cheaper. If you must drive to it yourself. And tired of the traffic jam.

Here is datasheet of LM3914 from
and this is the example of 0 to 5volts bar graph meter.
0-5 volts bar graph meter by LM3914

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  1. virender November 10, 2014
  2. satheesh G February 21, 2015
  3. momename February 23, 2015
  4. girish April 30, 2015
  5. Frank August 16, 2015
  6. dale September 16, 2015

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