Need opinions about my vu meter - thanks!

Other Hardware Audio
1

Hi, i am trying to build my own vu meter before xmas and so far i got a 0-4v output with sensibility and zero ajustments

Here is the schmematic if you want to take a peak: http://www.picaxe.com/docs/picaxe_sound.pdf
I got a KA2284 led meter : http://www.shenzhensum.com/products/datasheet/KA2284.pdf

I have one main question, the ka2284 turns on pin6(led5 output) when input is 6dB wich means 20x times more than VCC ??
I lost myself here, how can the amplifier step up even higher than de VCC???

Does someone knows a led driver that compares vcc with the input signal without amplifing it? I could ajust sensibility of the mic amplifier for a lower output 0-2v and then a led meter driver that compares those 2v with a 2v reference...

Anyone ? Thank you for reading :smiley:

2

the ka2284 turns on pin6(led5 output) when input is 6dB wich means 20x times more than VCC ??
No, it turns on VC5 2x (6 dB) after VC3, which is 56 mV x 2 = 112 mV. If you need lower sensitivity, use a resistive voltage divider at the input.