I strony support this. It is pretty well impossible to lay out a PCB with zero errors the first time around, if there's no link to a schematic. Saves you money, stress and lots of time. You need a nice schematic drawing to show here anyway.
gschem/pcb workflow:
- create schematic. start "gschem myamplifier.sch"
- add "footprint" to each component
- start "pcb myamplifier.pcb"
- run "import schematics"
- run "disperse all elements"
- place components manually or automatically / ratlines are shown
- traces can be added manually or by autorouter
For more details have a look at gEDA Project's Homepage
BR, Toni
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I strony support this. It is pretty well impossible to lay out a PCB with zero errors the first time around, if there's no link to a schematic. Saves you money, stress and lots of time. You need a nice schematic drawing to show here anyway.
I agree , out of ten - I did 5 with screen print errors , 4 perfect , and one
with a base-collector swap.
After 16 (semi) devices , mental "ratlines" break down.
Then there is time .... Sometimes takes a whole day to get one of those
16 device input stages correct. I'm going to diptrace now , I'll see how
I like the computer to take over this mentally stressful technique.
Too bad LTspice was not linked with any layout CAD's !
OS
I never tried it but it should be fairly straightforward to add footprints to parts in LTspice, and generate a netlist. IIRC LTspice can export several netlist formats.
See for example here: http://andyc.diy-audio-engineering.org/ltspice_freepcb_1.html . By our own AndyC. Wish he'd come back into the fold....
Jan
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That's one hell of a link , Jan. So good , I'm going to PDF capture it.
The only issue with porting the netlist is the import functions on
various CAD's and what they will do with your modified netlist outputs.
There does not appear to be any standard here ?
PS - yes , Andy was great teacher. But me thinks the BS that drove him away still festers strongly.
OS
Most CAD stuff is pretty flexible these days. What do you need? - the PCB layout needs a list of connections, like 'pin1 of R1 to pin6 of U3' type of text. This is the 'Export Netlist' function all have, most with a long list of available netlist formats.
The other thing is to tell the PCB program what the footprint for 'U3' or 'R1' is. Almost all schematic capture packages let you attach all kinds of attibutes to each part. For instance, on the part U3 that is designated an LME49600 you can attach (in the editor for the part) the attribute 'package = DIL08'. The PCB package then knows which footprint to attach, provided it has a footprint called 'DIL08' in its library.
Initially this takes some typing but ones you have a basic set of parts with the correct footprints it goes faster and faster.
BTW The possibility to attach attributes to parts can also (and often is) used to add attributes like 'order number = 12345678' and you can then generate a list of order numbers from the schematic. Really, really very flexible and excellent ways to cut down on errors.
Jan
The other thing is to tell the PCB program what the footprint for 'U3' or 'R1' is. Almost all schematic capture packages let you attach all kinds of attibutes to each part. For instance, on the part U3 that is designated an LME49600 you can attach (in the editor for the part) the attribute 'package = DIL08'. The PCB package then knows which footprint to attach, provided it has a footprint called 'DIL08' in its library.
Initially this takes some typing but ones you have a basic set of parts with the correct footprints it goes faster and faster.
BTW The possibility to attach attributes to parts can also (and often is) used to add attributes like 'order number = 12345678' and you can then generate a list of order numbers from the schematic. Really, really very flexible and excellent ways to cut down on errors.
Jan
I clicked on UK and the price changed to 15.6p each.
That needs vat added to come to 18.7p
I know from experience with Mouser and Mouser's Carrier that the price at my door is likely to be around double that, if I increase the order to avoid a separate delivery charge.
The names may not be literally the same. For instance, the spice model with package 'DIL-08' is not the same as the PCB program's package 'DIL08'. In these cases, just make a copy of DIL08 and save as DIL-08 in the PCB package.
Jan
Alan is in the US (according to his attached flag). As far as I am told, there is no sales tax for out of state Internet orders. Overnight courier is very cheap. 20 cents was quoted on purpose from the Mouser/US web site.
I am myself not stupid enough to order parts from Mouser, while living in the UK.
I regularly order from Mouser, being in Belgium, you collect orders till € 65 and all is free, no shipping, no customs. Can't do very much better.
Jan
And then you mention the "Ch" word ?
I just did that , (heatsinkusa , Nicholson USA taps , Oregon drill bits).
My asian experience is officially over
.The Asians DO make quite good through-hole PCB's , BTW. I'll limit
my "experience" to this.
OS
DipTrace looks really interesting. I checked their web page and it looks like they say that one or more companies switched from Eagle to it.
Cheers,
Bob
I can see why !
(Below 1-3) ran it through its paces.
- you need 2gig for everything.
-autorouting would use just one processor.
-3d rendering really likes a "real video card" (not onboard) and
a quad core processor. 39-45% of all 4 cores. (pix 3)
Yes , anything mixed digital/analog , like an amp with protection circuits ...
or a complex line stage// filter - Diptrace is the CAD !!
OS
Attachments
Hi Toni,
I will read a bit on the project page - thank you for the reminder.
The folks at DipTrace have been very good. They answered a couple questions, and they have a hobbyist price that saves from the commercial pricing. Exactly the identical software.
With the help and comments here, I am going to focus on DipTrace, but I'll keep my options open for the future. I can't say enough good about the people at DipTrace though. Very easy to work with, even from a hobbyist like me.
-Chris
Many thanks. That might allow me to get into the PCB part. I didn't attach footprints yet.
I will read a bit on the project page - thank you for the reminder.
The folks at DipTrace have been very good. They answered a couple questions, and they have a hobbyist price that saves from the commercial pricing. Exactly the identical software.
With the help and comments here, I am going to focus on DipTrace, but I'll keep my options open for the future. I can't say enough good about the people at DipTrace though. Very easy to work with, even from a hobbyist like me.
-Chris
Presumably you have references for these tests ...
... rather than "I met this guy, Otala in a pub who told me the latest fashion in amps will be incredibly high currents demanded from EVIL speakers". [1]
In more than half my life as a true speaker guru, I have encountered only one real life situation where a speaker will demand more from the amp than what you'd expect from the small signal impedance curve.
It is a fault condition. When it happens, you will be glad your amp DOESN'T give 300% more than you'd expect.
They quote Otala.
Perhaps one day, someone will record some 'music' (??) which sorta resembles these completely unrepresentative waveforms. You may like to simulate them in your favourite DAW and decide if anything close is worth listening to.
[1] This happened to me at AES Hamburg 1981 when I tried to drink the good professor under the table .. an endeavour doomed to failure. His revelations 'under the influence' have coloured my views of his work ever since.
Yes. He used the word 'fashion'
I hope I don't have to pay tax, I am actually going to order those resistor because it's flame retardant coating. For that, I am willing to pay more. I am sure it will still arrive sooner than the ones from China.....which is still not here yet.
I am so sick of waiting, After looking at Nattawa's board, I am just laying out another OPS board with 8 pairs of output transistors and transistors on both sides of the pcb just for the hell of it. Then been looking to set up for measuring THD. Seriously looking at QuantAsylum QA400 at this point.
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