# VU METER (Part-2) Using LM-3914 & LM-3915

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This is the second part of the music visualization series and in the video above i have shown how you can make a simple VU meter by using the ic called LM-3914 or LM-3915.

The part 1 is basically about how you can make the simple and cool looking VU meter by using the arduino microcontroller link to that is given as

https://www.instructables.com/id/UV-METER-Music-Vi...

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## Step 2: PARTS LIST

To make this cool looking UV meter we need these following things

1.LM-3914 IC

3.Copper dot PCB

4.18 pin IC Holder

5.Resistor(1.2k & 4k ohm)

6.Potentiometer (1K ohm) & Knob

7.Audio jack

8.Dc jack

9.LED (6-Green & 2-Blue & 2-Red)

10.some connecting wires

TOOLS REQUIRED

1.soldering iron

## Step 3: SPECIFICATION OF LM-3914 & DATASHEET

When looking at the LM-3914 ic datasheet these are some important features i found that i am writing here

Power Dissipation PDIP (NFK) == 1365 mW

Supply Voltage == 25V

Voltage on Output Drivers == 25V

Input Signal Overvoltage == ±35V

Divider Voltage == − 100 mV to V +

Reference Load Current == 10 mA

Storage Temperature Range == − 55 °C to +150 °C

If you want to have a look at the full datasheet of this ic you can go the following link

## Step 4: CIRCUIT DIAGRAM

After lots of test on the circuit which is provided in the datasheet i have recreated the circuit which is present above

The basic pin diagram overview is given as

LM-3914 Pin

1- led 1

2-GND

3-VCC

4-GND

5-AUDIO SOURCE

6-POTENTIOMETER

7-TO RESISTOR

8-GND

9-VCC

10 TO 18 -LED's

## Step 5: CREATED CIRCUIT ON BREADBOARD

To test the circuit above i have created the circuit on a sloderless prototype board or simply the breadboard

## Step 6: FINAL CIRCUIT PCB

After testing the circuit on the breadboard we can implement it on the PCB .

you can follow the instructions provided in the video above and get the basic idea that where to place the components and how to connect those

## Step 7: ADDING THE MUSIC SOURCE

After all these steps have been done at the last we can add the music source

And the music can be from any device like a smartphone or pc or laptop or i pod

i am using a audio jack spliter in the same way as i have used that in the part 1 or this music visualization series

the one end of that spliter will go to the headphones and the other one will go our circuit as shown in the picture above

## Step 8: THANKS FOR WATCHING

Thanks for visiting the following instructables
If you like the project make sure you give a like you can visit to my youtube channel and get so many similar projects by clicking the youtube link below

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## 3 Discussions

What power supply did you use specifically?

built a couple of these several years ago. I like it when you don't use micro processor for a simple task. great job