SparkFun Forums

[d4n1s]

Don't underestimate me . I have achieved more difficult things compared to my knowledge level and I have understand that
the best way to learn is to start from hard things. Step by step will get you boring! Exciting is when every post in this forum is
a vital piece of information.

ON topic:

What are you talking about there is clearly a resistor on the RTCX2 connection. Take a look at this. DOes this look more parallel to you?

Note: On the grnd pins I have removed the capacitors because as I have noticed in the schematic their not needed on every connection, and it makes sense in a way. I want the battery to get discharged smoothly, it doesn't interact in anyway with the micro-controller.
http://img266.imageshack.us/i/30277825.jpg/
http://img842.imageshack.us/i/50480361.jpg/

[Bryan Tong Minh]

With parallel I mean electrically parallel, not geometrically parallel. The power pins should be connected directly to the power source and near each power pin a capacitor should be connected between power and ground.

[d4n1s]

is this any better? ANything more to add?

[leon_heller]

It's still a rubbish layout. Where are the decoupling capacitors? There should be one for each pair of supply and ground leads.

[d4n1s]

on the olimex development board there is just one on the final grnd output? Why I should use more? DOesn't make sense. Aren't the capacitors used so that the battery gets discharged smoothly so that the battery can give me a smooth current?

[leon_heller]

They are needed to deal with the large current peaks on the different supply leads.

[d4n1s]

Here it is. I appreciate your help. But if there is something wrong with my board can you be more specific.
I really want to fix it and make it work so that would help me a lot.

[Polux rsv]

your blue layer is getting whorse. The long lines to capacitors are coils at high frequencies.
And your schematic is still wrong:
- each uC Vdd should be connected to positive power supply
- each uC Vss should be connected to negative power supply
- for each Vdd/Vss pair, add a capacitor connected to Vdd and Vss.
- each capacitor sould be placed few mm of uC pins, let say max 5mm
- fill blue layer of copper and connected to vss, so each capacitor is connected to Vss with less than 1mm connection.

Angelo

[leon_heller]

Your layout seems to be getting worse, and you seem incapable of applying what you have been told on several occasions. I'd abandon this board and learn PCB design with something much simpler; this is going to take months at this rate!

[d4n1s]

I just can't f-ckin get it... I searched the web, I read a book, but still I don't understand what you mean. In my stupid physics book there is nothing mentioned about all these things you guys are talking about. I guess because in their imaginary world things work like an utopia. Nevertheless I want to construct this pcb, does anyone have .brd which I can take a look at?

[Polux rsv]

Self quote

your blue layer is getting whorse. The long lines to capacitors are coils at high frequencies.
And your schematic is still wrong:
- each uC Vdd should be connected to positive power supply
- each uC Vss should be connected to negative power supply
- for each Vdd/Vss pair, add a capacitor connected to Vdd and Vss.
- each capacitor sould be placed few mm of uC pins, let say max 5mm
- fill blue layer of copper and connected to vss, so each capacitor is connected to Vss with less than 1mm connection.

Angelo

It could not be much simpler. Post your schematic.

Angelo

[d4n1s]

Sorry for the awful layout, I am self-taught and I got no clue on how to make it better... hope you understand it.

Also answer few of my queries about the things you advised me to do...

What is a uC? What do you mean by "for each Vdd/Vss pair, add a capacitor connected to Vdd and Vss.", for instance take the 2 pins of vdd and both connect them to the same point of the one capacitor end and than connect the capacitor to battery?
"fill blue layer of copper and connected to vss, so each capacitor is connected to Vss with less than 1mm connection." How can I do that on eagleCAD? I found a tutorial like 1 month ago, asked here if it was a good idea, and ppl said I shouldn't do it.

[leon_heller]

Drawing a proper schematic would help, no one is going to waste time trying to decipher that rubbish!

[d4n1s]

Drawing a proper schematic would help, no one is going to waste time trying to decipher that rubbish!

easy thing to say but HOW?

[cfb]

easy thing to say but HOW?

Learn how to walk before you start trying to run. You are way in over your head right now. Start with much simpler circuits first - there are some tutorials here; "Beginning Embedded Electronics" might be a good place to start:

http://www.sparkfun.com/tutorials

However, if you want to really make some progress you need to forget you ever said "I have understand that the best way to learn is to start from hard things. Step by step will get you boring!" Did you ever learn how to swim?