cmos dpdt [4066] rev. on ROG perf.

[donald stringer]

Image URL

http://img.photobucket.com/albums/v172/troublerat/IC-templatealternateschem.gif  
http://img.photobucket.com/albums/v172/troublerat/schematic_on_perf_with_color_finished.gif  
This yet another rev. of my dpdt but this is with run off grooves perf board and a smaller version of my own making. This is the alt. schem. My sole purpose of this is to give beginners like myself some idea of some switching options.  This is suppose to be my stress free hobby, I dont even pretend to do this for a living as I am a sheetmetal fab. but I am a little obsessed with these cmos things right now. All constructive critiscm is welcome as I can take it better than most. After you save yourself .20 cents and pull whats left of your hair out go and buy a bunch of 3pdt from aron. But as for me no way man I am going to continue my obsession with these things until I have this thing figured out. All these drawings were done in ms paint, once you get used to it its not quite as useless as I thought. Go to run off groove and make all there perf. board projects. and drink a cold one for me :lol:

[12afael]

mmm you don´t bias te input of the 4066? and the output???

[donald stringer]

Not on this one.I know that is the cure for making it clickfree. As R.G. suggest and I would do that if I had problems with it but so far I have built three #1 an dual loop box [this consist of just what you see#2 same circuit built on the double d dual pre-amp at runoff groove w leds #3 prof. tweed and a booster on that same size board, now thats the the one where I had started hereing some switching noise. I am not sure why it would start with that combination but it is not unbearable. This would probably be the point at which the bias thing would come in to play. One of my goals with these chips is to see just how few parts it takes to make them work together...I want to design an entire analoge type guitar effects box using nothing but cd4000 series chips.

[christian]

Great!

I just whipped this off from top of my head, but I posted it anyway(no quarantees that this will work!!), someone could check this out.
Parts are just on/off switch, led, 2 resistors, capacitor and 4066.

copy/paste this to your address bar:
http://www.angelfire.com/ego/sitruuna/images/dpdt.jpg
(angelfire doesnt give access to files from links!)

[donald stringer]

I will try that, christian. I am building a bread board and will try that one .I want to get it down to as few a comp.as possible. But the inv. work so well and clean therebut it looks like I will go back and read up some more on them.

[12afael]

the bias on the input is not only for the click

if you power suply only have 9v and 0v the negative part of the signal can´t pass through the 4066 it will sound bad I think

[Athin]

if you power suply only have 9v and 0v the negative part of the signal can´t pass through the 4066 it will sound bad I think

actually, no - if U look @ the datasheet you'll find that the signal can go from -0.5V to VDD +0.5V

[christian]

if you power suply only have 9v and 0v the negative part of the signal can´t pass through the 4066 it will sound bad I think

That´s true if you are passing -9v there too, that would most likely kill the CMOS. but 9v/0v are used so that there is a virtual gnd which stands in 4.5V, so that actually makes +/-4.5V once you DC couple the circuit.(which I forgot in that little thingie I drew :oops: ). Bias the inputs with equal resistors to 9v and 0v, so the chip thinks it´s running on that +/-4.5v

[12afael]

actually, no - if U look @ the datasheet you'll find that the signal can go from -0.5V to VDD +0.5V

mmm maybe you could damage the sustrate if you put less voltage that -0.5v .

sometimes diferent datasheet says different things of the same chip-

[Athin]

dunno, I think it'd rather clip the part of the signal which is lower than -0.5V.