Author Topic: Question Regarding Diodes in Schematic  (Read 12128 times)

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Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #25 on: September 25, 2016, 09:48:36 pm »
Oh. I've made some breakout boards for the LM358 as I purchased a bunch of the mini so8's and have gotten good and bad results. But mostly bad when using only half the chip. When I've done this I do nothing with the other half. I guess this could be why I've had such mixed results.

Please tell me I'm also correct on the audio/signal input. The Audio neg goes to ground and the Audio + goes to IC1A +in. Right?
 

Offline ataradov

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Re: Question Regarding Diodes in Schematic
« Reply #26 on: September 25, 2016, 09:51:57 pm »
I guess this could be why I've had such mixed results.
That depends on what was the experiment. The worst that can happen is oscillations on the output, since inputs are floating.

Please tell me I'm also correct on the audio/signal input. The Audio neg goes to ground and the Audio + goes to IC1A +in. Right?
Audio in is a real ground and C1 (where it says INPUT).
Alex
 

Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #27 on: September 25, 2016, 10:00:20 pm »
Audio in is a real ground and C1 (where it says INPUT).

All that we've discussed and this is what has me puzzled. What do you mean by this?
 

Offline ataradov

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Re: Question Regarding Diodes in Schematic
« Reply #28 on: September 25, 2016, 10:07:53 pm »
Audio input is SGND and IN signals.

This circuit will require a lot of tweaking, it will not work out of the box. Also, breadboard is no the best way to prototype this, stray capacitance of the breadboard will make it a nightmare.

Also, start building it from the end. Build one indication chain and see how it works if you feed it with different voltages, then build filters, then buffers, etc.
Alex
 
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Offline T3sl4co1l

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Re: Question Regarding Diodes in Schematic
« Reply #29 on: September 25, 2016, 10:58:55 pm »
If no part number is given, then the symbol is nearly meaningless.

It could be a rectangle with wires coming out, and the schematic would be identical.  No? :)

One would suppose the author intended the symbols, that you should use ESD-protected types.  But this kinda begs the question why................

Tim
Seven Transistor Labs, LLC
Electronic design, from concept to prototype.
Bringing a project to life?  Send me a message!
 
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Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #30 on: September 26, 2016, 12:19:42 am »
Yeah, I'm really not sure. It was an instrucables that I found. Unfortunately they want visitors to pay $35 for membership to get the rest of the files, so that's not happening.

What else is not happening is anymore PCB etching until I get this completely figured out. You all have done a great job getting me on track with this hokey schematic and Alex said just what I was thinking - start at the end.

I notice that the LED portion is essentially what's inside an LED driver such as AN6684 and others I had purchased. So I like the idea of building a driver circuit and I will do just that. First.

P.S. Anyone PCB etching using the inkject, muriatic acid, hydrogen peroxide method... I've found the absolute best paper is Q1987A HP glossy brochure paper instead of photo paper. Rarely have a trace not transfer. Much faster and less expensive!!
 

Offline ataradov

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Re: Question Regarding Diodes in Schematic
« Reply #31 on: September 26, 2016, 12:26:50 am »
Yeah, I'm really not sure. It was an instrucables that I found. Unfortunately they want visitors to pay $35 for membership to get the rest of the files, so that's not happening.
They want $35 to view full article on one page and download PDF. You can click "Next Page" many times and get all the information.

What else is not happening is anymore PCB etching until I get this completely figured out.
Use prototyping boards. And then OSHPark.
Alex
 
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Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #32 on: September 26, 2016, 12:42:25 am »
uhhh, that doesn't work for me Alex. Maybe in a few years I'll look at all them parts and pieces and make sense of it. I'm having trouble with the entire schematic! LOL. Many small pictures doesn't help me unfortunately. :-//

Thanks again. Thank you all very much.
 

Offline Gary350z

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Re: Question Regarding Diodes in Schematic
« Reply #33 on: September 26, 2016, 12:14:15 pm »
It was an instrucables that I found.

Give us the link to the instructable.
 

Offline bumba000

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Offline ataradov

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Re: Question Regarding Diodes in Schematic
« Reply #35 on: September 26, 2016, 05:18:11 pm »
So now we know that LED used is GM5BW96385A and it has the following note in the DS:

Quote
Similar part to GM5BW96380A, but includes self-protection against static electricity
So the mystery of the diode is solved.
Alex
 
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Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #36 on: September 26, 2016, 07:47:09 pm »
Where in the heck did you come up with GM5BW96380A? I don't see that mentioned anywhere.
 

Offline ataradov

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Re: Question Regarding Diodes in Schematic
« Reply #37 on: September 26, 2016, 08:08:20 pm »
On indestructables click next until you get to the last page, there will be schematic and PCB files in Eagle format.
Alex
 

Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #38 on: September 26, 2016, 08:37:07 pm »
oh. well that explains it. I don't have a program to open either of those two files. I did grab that eagle file, but yeah, couldn't open it. So I guess it would have been pretty helpful to us all had I linked to that originally.

Ahhh, sorry and thank you.  :)
 

Offline ataradov

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Re: Question Regarding Diodes in Schematic
« Reply #39 on: September 26, 2016, 08:39:09 pm »
oh. well that explains it. I don't have a program to open either of those two files. I did grab that eagle file, but yeah, couldn't open it. So I guess it would have been pretty helpful to us all had I linked to that originally.
Eagle is free, you can just download and install it.

Also, in this specific case, I don't have it installed either, but those files are human-readable XML files, I just opened .sch in a text editor and searched for one of the LED names on your schematic.
Alex
 

Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #40 on: September 26, 2016, 11:38:08 pm »
I did try to open the file using acrobat, firworks and notepad++ all to no avail. hrmmm. I'll try again? Heck maybe just install eagle?? LOL I thought I remembered it being a trial. It could just be that it's been a while and I don't remember clearly. Either way. Thank You.
 

Offline ataradov

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Re: Question Regarding Diodes in Schematic
« Reply #41 on: September 26, 2016, 11:40:44 pm »
Notepad++ must be able to open it. The worst case scenario - rename them into .xml.

Eagle is completely free with limited board size and number of layers. Free version can open any board, but won't let you edit outside the limited area. I'm pretty sure everything you'll find on the instructables site was created in a free version.
Alex
 

Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #42 on: September 26, 2016, 11:54:47 pm »
Oh Yeah, it all works. Not sure why I couldn't open that .sch with notepad++ before, but I can now. I also have re-installed eagle and went with the freeware license instead of trial. I guess I'll have to learn eagle at least a bit, but why can't I see the part models in the eagle, but when I open the same file in ++ there it is?!

NutZ! every part used is listed!  :-DD
 

Offline ataradov

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Re: Question Regarding Diodes in Schematic
« Reply #43 on: September 26, 2016, 11:56:36 pm »
but why can't I see the part models in the eagle
They are not normally shown on the schematic, but if you open component properties, you will see all the info you need.
Alex
 
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Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #44 on: September 27, 2016, 12:32:27 am »
Oh yeah I'm starting fresh here. I first had to figure out which tool I needed to be able to select the components. But then... Oh only then are all of the juicy details revealed. All them details...

Thank You Alex.
 

Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #45 on: September 30, 2016, 02:34:58 am »
Would you expect output pin 7 of the first filter to always measure 4.92 V? It does until the frequency is between 40 and 60 hertz during that time the output pin 7 then drops to around 4.7 V. Is this how the circuit should behave? Even without using the first half of the first op amp I still get 4.9...
 

Offline ataradov

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Re: Question Regarding Diodes in Schematic
« Reply #46 on: September 30, 2016, 02:42:15 am »
Would you expect output pin 7 of the first filter to always measure 4.92 V?
It should be VCC/2, so yes, ~5 V sounds about right.

It does until the frequency is between 40 and 60 hertz during that time the output pin 7 then drops to around 4.7 V.
What is the amplitude of the input signal and what is the source?

The first half is a simple 1:1 buffer, so make sure that is works as such and leave it in place for the following experiments.
Alex
 

Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #47 on: September 30, 2016, 02:50:13 am »
Okay so I wasn't quite sure what are one and are two should be and didn't want to bother asking you I used 1M and 10K so I have some crazy game going on there. As for amplitude I'm not quite sure. Here's what I've got I'm using my cell phone with a signal generator app every time I turn it on it cranks my volume up to 100 and 50% so I turned it back down to 75% then the signal generator has a game and I said it to -9 to -7 DB. Any lower the output voltage stays at 4.92 no matter what higher and I don't remember what happens...
 

Offline ataradov

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Re: Question Regarding Diodes in Schematic
« Reply #48 on: September 30, 2016, 02:54:35 am »
You can't just feed the signal from the phone directly to IC3A input. Remember, the signal needs to be centered around 5V. That's what IC1 does. So if you want to use the phone as the source, you need to pass it though IC1 circuit.
Alex
 

Offline bumba000

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Re: Question Regarding Diodes in Schematic
« Reply #49 on: September 30, 2016, 03:11:40 am »
using IC1 I believe a buffer. at first I figured might be causing a problem which is why the output voltage was so high I was not expecting that. so I eliminated it to see if there would be any difference and I don't think there was. I guess I was kind of expecting to get next to nothing out of it until the frequency was right and then there would be enough voltage to pass the first couple of diodes turning on the LEDs. I have several types of LED drivers that I planned to use but in this case they would always be on until the frequency matched and then they would go off. I think I need to spend a little time and figure out exactly what's going on here because I apparently don't understand. I have it working but I don't understand...
 


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