Where do you guys make your prototype PCBs?

[michal_k]

Hello everybody,

It's the first diy I'm doing since I moved out from my mother country and I'm a little bit lost so I need your assistance. Where do you(european) guys send your prototype pcbs to be manufactured?
I've just started drawing a simple 51x connector breakout board. Single sided, small, and I don't even need a soldermask for that.


I havent added connections for +-24V because I'll be using a greenpre psu to power a module under test. Any obvious mistakes?

 

[Speedskater]

Are those XLR connectors for audio?
If so, pin #1 should not be connected to the PCB, it should go straight to the chassis.

 

[ruckus328]

Are those XLR connectors for audio?
If so, pin #1 should not be connected to the PCB, it should go straight to the chassis.

Well no, incorrect.  He's using PCB mount XLR's, so they have to go to the board.  From there though they should go to some sort of feedthrough connector to go to the chassis (which he has).  He's also added a jumper so he can disconnect the input/output from ground should he have to which is also a good thing.  However, the ground branch off to the 36 Pin connector needs a jumper so you can sever the connection to ground in the same fashion.  Depending on where that goes to it might need its own return path back to the star ground.

 

[3nity]

Futurlec or gold phoenix.
Check ebay for really good deals too.
Thansk

 

[Speedskater]

Are those XLR connectors for audio?
If so, pin #1 should not be connected to the PCB, it should go straight to the chassis.

Well no, incorrect.  He's using PCB mount XLR's, so they have to go to the board.  From there though they should go to some sort of feedthrough connector to go to the chassis (which he has).  He's also added a jumper so he can disconnect the input/output from ground should he have to which is also a good thing.  However, the ground branch off to the 36 Pin connector needs a jumper so you can sever the connection to ground in the same fashion.  Depending on where that goes to it might need its own return path back to the star ground.

Well no, incorrect.  The traces should stop right by the jumper connectors (E$4 and E$5) so that a wire from each jumper can go straight to the chassis near the connector.  Pin #1 is not part of the star ground.

 

[michal_k]

Thanks for your replies. The reason I thought I might want to connect pin1 to pcb ground is that I won't be using any enclosure. It's supposed to be a fast way to connect a 500 module to a psu and see if/how it works without hassle of carrying all the lunchbox to the lab.
Should I remove all the traces from pins 1?

However, the ground branch off to the 36 Pin connector needs a jumper so you can sever the connection to ground in the same fashion.

I don't get that part. Ground from 36pin connector goes straight to PSU, is there a need to cut it in certain circumstances? Will the circuit work at all then?

 

[ruckus328]

OK, some clarification - (IN MOST APPLICATIONS) pin 1 on input and output should go right to star ground, shortest path possible.  Enclosure or not they need to be grounded, but grounded to the rest of the unit at a single point.  Sometimes pin 1 on the output is left floating.  The rest of the circuit's ground should go to star ground as well.  But they generally shouldn't all come together and then go to star ground like you currently have it.  Now these are general guidelines and ymmv, it might work ok as you have it fo your application, but it might not, which is why I recommend you add a jumper on that trace so you can disconnect it and run a seperate wire for your power supply ground to the star ground if you need to.

Now, I'm not sure where your star ground's going to be since there's no actual enclosure.  You could very well make this board your star ground.  If that's the case, than your PS ground would come to the board as you have it, and your IEC ground would come to this board as well and you'd be good.  I'd still add the jumper though, just to allow yourself every option possible.

 

[mobyd]

I've used all of these :
China : Gold Phoenix, OurPCB, Sure Electronics* (my current favourite)
Bulgaria : Olimex
Thailand : Futurelec
Malaysia : Custom PCB (AKA Silver Circuits)
Australia : IMP, BEC, Entech
Our local (Auckland NZ) PCB maker went tits up at close of business today so no use mentioning them.
M

 

[michal_k]

thanks for clarification. I've put a star ground in the pcb with some pads to hook it up to the enclosure if I ever decide to make one. Also changed goldpins to a submini toggle switch for connecting boards.



I'm sending gerbers to fabication today. The cheapest service I've found is a polish one, 8usd for two boards with shipping

Now I need to order some parts at farnell.

 

[Kingston]

I'm sending gerbers to fabication today. The cheapest service I've found is a polish one, 8usd for two boards with shipping

Where?

 

[michal_k]

www.prototypy.com.pl

it's in polish, but if you need any help i can translate something for you.

 

[Kingston]

Thanks!

 

[Speedskater]

Still, XLR pins #1 should NOT in any way be connected to the audio signal / power supply star ground.
The XLR pins #1 should be connected directly to the chassis (none available in this situation).
The the audio signal / power supply star ground is also connected to the chassis, but by another wire route.

 

[ruckus328]

Still, XLR pins #1 should NOT in any way be connected to the audio signal / power supply star ground.
The XLR pins #1 should be connected directly to the chassis (none available in this situation).
The the audio signal / power supply star ground is also connected to the chassis, but by another wire route.

No, sorry, you're wrong - that's not always correct.  There are quite a few projects around where audio ground connects to pin 1 and then star ground, and whether to connect pin 1 direct to the chassis or to run it to star ground is a matter of much debate.

 

[JohnRoberts]

Still, XLR pins #1 should NOT in any way be connected to the audio signal / power supply star ground.
The XLR pins #1 should be connected directly to the chassis (none available in this situation).
The the audio signal / power supply star ground is also connected to the chassis, but by another wire route.

No, sorry, you're wrong - that's not always correct.  There are quite a few projects around where audio ground connects to pin 1 and then star ground, and whether to connect pin 1 direct to the chassis or to run it to star ground is a matter of much debate.

http://pin1problem.com/

I am not aware of any credible reason for connecting pin 1 to audio ground. While people may debate it, that doesn't mean they should be listened to.

Audio ground will often be referenced to power ground through some compliance. Power ground will typically connect to chassis ground at some point. While this may sound like the same thing, to the electrons it isn't...

Ground is a concept, not a single voltage node.

Best practice for interfacing pin 1 is published and pretty well known (these days at least). There is no reason to repeat old mistakes in grounding.

JR

 

[ruckus328]

I am not aware of any credible reason for connecting pin 1 to audio ground. While people may debate it, that doesn't mean they should be listened to.

No argument, which is why I said to add a jumper and sever the connection to audio ground.

Audio ground will often be referenced to power ground through some compliance. Power ground will typically connect to chassis ground at some point. While this may sound like the same thing, to the electrons it isn't...
Ground is a concept, not a single voltage node.

No argument, no argument, and no argument.  But "typically" is the key word here.  I was merely stating that there could always be circumstances where something may or may not work.  And in this situation, things become not so black and white, because there is no enclosure.  And OP was being instructed to leave Pin 1 floating, which could very well cause issues.

Best practice for interfacing pin 1 is published and pretty well known (these days at least). There is no reason to repeat old mistakes in grounding.

Yes, I've read all of those many times.  Have also read alot of opinions that pin one should go to star point as opposed to chassis or that it makes no difference either way.  Now who is right, I don't know......... I've done it both ways and never encountered any grounding issues.

 

[kepeb]

looks to me like theres only one way to settle this...

 

[ruckus328]

Just build it up dude, you'll be fine.  You have it so you can ground it any which way you need to, which was the whole point.  Think the fact there is no enclosure keeps getting overlooked.  Good luck with it!

 

[Kingston]

pin1 goes directly to chassis or chassis star ground. always works.

if it doesn't, the design is failed elsewhere.

end of debate.