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Topic: My first pcb (Read 5429 times) previous topic - next topic

Nick_Pyner

#15
Mar 02, 2013, 06:10 am Last Edit: Mar 03, 2013, 12:53 am by Nick_Pyner Reason: 1


I've managed to design my very first pcb. It's a sensor board, with room for an atmega328 and 3 analog inputs, as well as a status LED and a 2x4 pin-header where is meant to go a nordic transceiver breakout module.



Very interesting. The first dedicated board I have seen and, if I can be sure of the Nordics delivering the goods, I am looking at doing pretty much the same thing.

Quite apart from the extra cap etc., I wondered about avoiding some of the through-board transitions. UI assume the large rectangle at the top is a regulator and can be rotated, and the nearby terminal can be reversed.

I submit the diagram below as intellectual exercise...

I would be interested to see how you finish up with this.

harleydk


Very interesting. The first dedicated board I have seen and, if I can be sure of the Nordics delivering the goods, I am looking at doing pretty much the same thing.
I submit the diagram below as i9ntellectual exercise...
I would be interested to see how you finish up with this.


Hello Nick, thanks for the inspiration & I'll be sure to post the re-done schematic here. It's not the first dedicated board I'm afraid - search google for 'maniacbug' and you'll see some great stuff built with the nordic chip. It will deliver, I've had succesful tests with so I'm happy to go with it and I'm sure you will be, too.

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My hopefully helpful blog at technicalstuffhopefullyuseful.blogspot.com

harleydk

Hello again,

as promised here's the revised board, in the case someone would find it useful.

Routing below the MCU certainly made it much easier!



P.S. I reverted to through-hole components, because I wanted go easy on myself, this being the first board and all...
---
My hopefully helpful blog at technicalstuffhopefullyuseful.blogspot.com

Jack Christensen

Are ground pins 8 and 22 connected? They should be.
MCP79411/12 RTC ... "One Million Ohms" ATtiny kit ... available at http://www.tindie.com/stores/JChristensen/

harleydk


Are ground pins 8 and 22 connected? They should be.


Ahem *cough* they are now. Thanks.

In case anyone could find use for this, here's the link to the Fritzing file:
https://docs.google.com/file/d/0B8b-I3PiuN9lZ1FsdHU4VnNROG8/edit?usp=sharing
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My hopefully helpful blog at technicalstuffhopefullyuseful.blogspot.com

gutbag

#20
Mar 06, 2013, 06:26 pm Last Edit: Mar 07, 2013, 07:27 am by CrossRoads Reason: 1
Good progress...

A few more vias could be removed by re-routing tracks. For example, the one at the top of the 328p is redundant - you could just route the track on vertically to the next via. Also, the two under the 328p could be removed by taking a track from pin 8 below ResR and up to the LHS of PwrC1.

Will the PCB be through-plated? If not, you have to be aware when routing tracks to top-side pins, that you can actually solder the pin on the top side, to make the connection from one side to the other using the leg (e.g. 328p pin 8 ). This isn't possible with an IC in a socket, for example, but may be if you were soldering the 328p directly to the board.

I presume yellow is bottom, orange is top?

The top side track from 328p pin1 could be avoided by routing the track that's currently in the way below ResR.

Hope that helps...

gutbag

That smiley should be pin EIGHT - how do I stop it doing that?

CrossRoads

I don't see Avcc connected.
I don't see any 0.1uF caps on the power pins.
Are you programming the chip on the board? Or elsewhere, and then plugging it in?
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

Coding Badly

That smiley should be pin EIGHT - how do I stop it doing that?


• Click Modify (upper-right corner of your post)

• Click Additional Options (lower-right corner of the edit window)

• Ensure Don't use smileys is checked

• Click Save

CrossRoads

8) vs 8 ) - just add a space.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

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