Hi, I am a beginner in electronics world. Just I made a LED spectrum analyzer with IC LM3915N. I use 2 IC (LM3915N) for left and right. I add 10*3 LED (normal 2 pin) for each IC. IT's working fine. But I want to add more LED (like 10*10) for each IC. Could possible? If so could anyone help me on this. Another point, if I want to use RGB LED instate of normal LED, what is the circuit diagram.

Thanks
Anjon

 

Please post your schematic and any other descriptive information available so we can answer your question.

What is it that you wish the additional LEDs to do -give a wider frequency range, indicate amplitude...or?

 

Please post your schematic and any other descriptive information available so we can answer your question.

What is it that you wish the additional LEDs to do -give a wider frequency range, indicate amplitude...or?

Thank you sir. I use this circuit.

 

This looks like a simple bar graph circuit rather than a spectrum analyzer.

What do you want the additional LEDs to do? Greater voltage range, finer resolution...?

 

Using LM3914 for the verticle and 4017 for horizontal scanning, you can make a 10x10 LED scope.
For better sensitivity, you can add an opamp before the LM3914.

Allen

 

View attachment 126808
Using LM3914 for the verticle and 4017 for horizontal scanning, you can make a 10x10 LED scope.
For better sensitivity, you can add an opamp before the LM3914.

Allen

Thank you so much. Let me try. Another question if I use LM3915 (your suggestion LM3914) have there any problem? If I want to use RGB LED what is the circuit diagram.

Anjon

 

Another question if I use LM3915 (your suggestion LM3914) have there any problem?

LM3915 is logarithmic, LM3914 is linear.

Cascading 2 LM3915 (from the TI datasheet):

 

Now you have two different solutions that do different things, but you still have not told us what you want the extra LEDs to do.