I tried a new version of ExpressPcb, (Plus). It was rather easy to do, but ExpressPCB Classic is better. With Plus, I couldn't get the track width to stay at the size I wanted; it always reverted to default setting, which made for a lot more clicking/work. Yet, I didn't have to bugger around with schema capture, and sizing the board (or whatever the term is for setting your copper canvas to 100mm x 100mm) was straightforward. I tossed in extra pads for pro-typing convenience, and left enough spacing so I can dice it up into six individual boards on a wet-saw.



This is what I came up with two hours of work. Still no gerbers with this software (the fab that provides this freeware wants to capture all it's users). I can print it (it has options for transparency and iron-on style, which is nice, but you can't save the image, so a screen capture is the only way I could share it.
I couldn't find a dip-8 socket in the library, so I used an ne555, just to get the pin spacing, then deleted it as I don't want vias or thru-hole pad shorting out to the copper on the backside. In my idea, you can just bend the pins flat on a DIP-8 componet, solder it surface-mount style, and you're off to the races, programming-in-solder as you go. But I still have nothing, as there are no gerbers. Just a glorified concept for now.

In snooping around online, I found a fellow that offers a service to turn ExpressPCB files into gerbers for as low as $5 bucks. If I can't jump the hurtles with Kicad, Eagal, etc., I might have to go that way.

 

What is the size of those large pads in mils and is the IC a standard 8 pin SMT?

 

I agree with using a schematic to make a real circuit, but for a breakout board, it is nothing but a waste of time.

The big advantage of using the schematic is that it checks all the connections for you. In the case of my tool, it also inserts all the pats roughly in the same relative positions as the schematic, which I thought would be useful, but turned out I always completely rearrange them.

Bob

I admire your skill in writing a pcb-cad program. Maybe you can offer it someday, with a 30-trial.

 

Our posts crossed each other. What is the size of those large pads in mils and is the IC a standard 8 pin SMT?

 

What is the size of those large pads in mils and is the IC a standard 8 pin SMT?

No, this is not SMT. It's more like DIP (dual inline package) converted to surface-mount by smashing the pins flat.

Round pads are 0.250 inches, and
0.290 x 0.060 is the size on the DIP-8 pads

I'm not ancient, yet, but my vision isn't what it used to be, so I avoid soic/smt whenever possible. So far, I can get
everything soldered down okay, but repeated heating eventually lifts tracks and results in solder-bridges whenever I build a prototype that requires many changes and testing. I'm moving away from strip-board for this reason, and either create pads with tin-snips, & glue them down, or use small diamond hole-saws to create island-pads in the copper, which also provides a large ground-plane surface area, which I find very convenient. I learn better holding a soldering iron.

 

I also wanted to add this, my image shows six "pannelized" breakouts. If I wanted, with this design,
use two breakouts to create a pad that supports a fourteen to sixteen pin DIP.

 

I agree with using a schematic to make a real circuit, but for a breakout board, it is nothing but a waste of time.

:: hand to face ::

 

There is another option, one that I have used to create quite a few circuit boards, because my employer at the time did not own any circuit board design programs. I was quite good with Autocad, and that program can very easily design printed circuit boards, even multi-layer boards.
Autocad iis quite expensive, but for a board layout there are many free mechanical cad programs available. You do need the ability to draw lines with some width, and the ability to draw donuts, or whatever the program calls them. That is about as simple as it can get, but it works much better than the tape and mylar method. And most of them can drive a printer.

 

:: hand to face ::

Seriously? What advantage do you see for a schematic for the design the TS is talking about?

Bob

 

AutoCAD is perfectly capable of drawing (pretty much anything), but cannot (as far as I know) output a gerber file.

Hamlet, is this a one-off thing, or are you likely to want to design other PCBs?

 

What a cad program CAN do is produce an exact scale plot of the artwork. And at leat the PCB houses that I have dealt with were able to somehow produce the files they needed from a cad file, with each board layer in a separate drawing layer.

 

AutoCAD is perfectly capable of drawing (pretty much anything), but cannot (as far as I know) output a gerber file.

Hamlet, is this a one-off thing, or are you likely to want to design other PCBs?

https://www.pcbway.com/blog/PCB_Layout_Software/How_to_generate_Gerber_from_AutoCAD.html

 

A cad program may be able to drive a plotter and print the resist pattern directly on an unetched piece of board stock. THAT would be really cool. I actually saw that in process back in about 1980. There was an adapter made to hold a resist pen. I don't recall the brand of plotter, but it connected to the serial port.

 

A cad program may be able to drive a plotter and print the resist pattern directly on an unetched piece of board stock. THAT would be really cool. I actually saw that in process back in about 1980. There was an adapter made to hold a resist pen. I don't recall the brand of plotter, but it connected to the serial port.

That is exactly how I make a lot of my proof-of-concept circuits. I use an ancient CAD program and an HP 7221T flatbed plotter with an extra fine point industrial Sharpie marker to do it. Back when the plotter was new, it's list price was $5K... I got mine from ebay for $35+s&h about 10 years ago. The thing is a little tank and works wonderfully. The main limitation is that you're pretty much stuck with the pen tip width for minimum trace width.

If I want something production quality, I use Eagle. Which, by the way I was able to use to toss together a breakout board similar to what the OP is describing without a schematic in about 5 minutes. It actually took me longer to type this reply than it did to create that artwork.

 

kicad's really not that hard after getting used to it. When I first tried it I hated it, now I find it easy and gets done exactly what I need it to do. Give it another go and goof around for an hour or so. You'll get the hang of it.

 

k

AutoCAD is perfectly capable of drawing (pretty much anything), but cannot (as far as I know) output a gerber file.

Hamlet, is this a one-off thing, or are you likely to want to design other PCBs?

I am going to design other pcbs. My frustration was that I wanted to do something which I thought should be dead-simple, but turned out to be as enjoyable as a bag of snakes. All these programs are very proscribed, and the work-flow is designed with the aim of facilitating rather complex designs, but to get my feet wet, all I wanted to do was a simple breakout board, just 100mm square, because many fabs in china use this size as their rock bottom price/offering, and that's more than enough acreage for the little electron-farms that I want/need to cultivate right now.

 

CERTAINLY creating the schematic can be a challenge with the PCB layout programs. I found that with the Eagle program, after doing MANY circuit drawings with Autocad. They are very much different in many different ways. So don't be discouraged too much.

 

Many seem to be disappointed that multi-featured programs that offer many in depth features such as AutoCad, Kicad etc, have a long learning curve, i.e. "are NOT Dead Simple" ?
It stands to reason You cannot have one without the other, I got in to Autocad when DOS was still a viable programming art, I am still learning some of the tricks.
The same goes for Kicad that started in 1992 and now has the backing of Cern and is still being developed, with ver 6 due to be released this summer.
There are Many tutorials out there, both of Kicad origin and 3rd party versions.
I found that (free) Kicad is easily a contender to the high priced types such as OrCad, which BTW, also has an eqully long learning curve.!.
Max.

.

 

Okay, much good input. Many thank-yous to all for the tips & encouragement. I'll keep trying.

 

Many seem to be disappointed that multi-featured programs that offer many in depth features such as AutoCad, Kicad etc, have a long learning curve, i.e. "are NOT Dead Simple" ?
It stands to reason You cannot have one without the other, I got in to Autocad when DOS was still a viable programming art, I am still learning some of the tricks.
The same goes for Kicad that started in 1992 and now has the backing of Cern and is still being developed, with ver 6 due to be released this summer.
There are Many tutorials out there, both of Kicad origin and 3rd party versions.
I found that (free) Kicad is easily a contender to the high priced types such as OrCad, which BTW, also has an eqully long learning curve.!.
Max.

.

Max, I was given a rather obsolete version of Orcad, and you are certainly correct about the long learning curve. And there were issues getting it to even load with windows XP, so it was "not quite right." But certainly it would be handy to be able to use. The local board producer that can adapt Autocad drawings for board production is far from cheap. And on top of all that, the computer able to run it is the one that suffered the lightning strike damage.
And the issue with the Eagle PCB software is that it is so very different from what I was quite good with. Yes, my first ACAD experience was with version 8, wich was replaced by version 10 at that place quite soon.