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Can anyone simplify me this scheme? Answered

Can anyone make this scheme clearly for me? I don't understand some parts. So, can some one draw ona a paper how that should like? (Not drawing the simbol than drawing the parts like they look)

Thank you



Best Answer 8 years ago

The LM315 chip does all the work internally, so thankfully that part is easy.

The chip has a notch at one side.  Put that notch at the top and you have 18 pins, 9 on each side.  The numbering starts from the top left, works its way down the left side (1-9) then counts back up the other side 10-18).

The picture I have attached shows this type of chip turned on its side.  Just draw a similar chip on paper and follow the same numbers.  Write numbers next to each pin if you find it hard to remember.

Try prototyping this with a breadboard first...

'input' is a little confusing - it uses a 10k potentiometer - not sure if they want you to use an audio pot or a linear pot, just depends on the sensitivity.  Both will work, one better than the other.  There will be 3 pins on the pot, represented (in order) on the schematic by 3 lines coming off it - in, wiper, and out. 

Hook the middle (wiper)  to pin 5 on the lm315 
Hook the top of the pot to the audio signal through a 1uF capacitor
Hook the bottom of the pot to ground directly.

Hook 6 and 7 together, and then connect them to ground with a resistor.
Hook pin 2, 4, and 8 to ground directly.

LED arrows point from + to -, double check their polarity, because its important.
Note that all the + sides of the led are connected together, straight to 12V

The pin numbers on that chip seem somewhat random, its just what worked best for the engineers to cram the circuit inside.  They are in order on that diagram -- 1 18 17 16 15 14 13 12 11 10.  This is actually quite easy, since LED 1 is in the top left corner of the chip, then all the rest of the LEDS are in a row, going from top to bottom down the right side of the chip.

Hook pin 9 to +12 volts directly.

power it up and add audio...see what happens!


**note that image is copyright someone else, I googled it; and am using it under fair use.  Copyright holder of this image may complain to me directly if theres a problem :D

just seemed bad to post copyrighted info on a creative commons site... :D


8 years ago

frollard, verry nice, I'm thanks. So, I need a audio wire with two wires and ground? The circled parts on picture are unknown for me. First left up, i understand it's ressistor, but that arrow what means? Then up, what is that pin in middle of chip? And what is that square? And down, some sign, what??? I'm sorry, I'm a jus ta begginer.


That shows you how to wire the thing up pretty-well, where do you want more information?