LED Sound level display circuit by using IC LM3915


Posted on Feb 5, 2014

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. The audio sound level LED display circuit can o


LED Sound level display circuit by using IC LM3915
Click here to download the full size of the above Circuit.

perate 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.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Voltage Comparator Switch
    Simple CB transmitter with BD329
    20Khz-arc-welding-inverter
    Bug Detector Circuit
    Another kind of relay driver board used to utilize your old PC
    SI Programmer
    Indoor Weather Station using Arduino
    Bus Interface Description RS422
    Constant Current LED Drive



    Top