Author Topic: First time designing a PCB  (Read 1333 times)

OiMcCoy

Re: First time designing a PCB
« Reply #20 on: February 15, 2021, 09:40:16 AM »
Well I took a shot and ordered 3 prototypes printed from OSH.

I know its probably old hat to most of you, but considering I am not a technically inclined guy I am pretty happy that I went from breadboard to PCB printing with in a few days.

Thanks everyone for all the help. This has been a lot of fun.

Fancy Lime

Re: First time designing a PCB
« Reply #21 on: February 15, 2021, 11:55:56 AM »
Glad we could help and glad it went so smoothly for you. I've been stuck at that stage for months now. Oh well, I'll get it done some day...

In the meantime, do you mind telling us where you found those pot footprints? Are they from an external library?

Andy

OiMcCoy

Re: First time designing a PCB
« Reply #22 on: February 15, 2021, 12:16:48 PM »
Its from the standard library. Omeg PC16UB Vertical. I believe in the Pot THT section.

I got to say this is a lot of fun. I am probably biting off more than I can chew but I just laid of the schematic for a Big Muff with a mid control.

davent

Re: First time designing a PCB
« Reply #23 on: February 15, 2021, 12:29:54 PM »
Its from the standard library. Omeg PC16UB Vertical. I believe in the Pot THT section.

I got to say this is a lot of fun. I am probably biting off more than I can chew but I just laid of the schematic for a Big Muff with a mid control.

It is a lot of fun, can become an addictive activity unto itself, i liken it to doing crossword puzzles.
dave

OiMcCoy

Re: First time designing a PCB
« Reply #24 on: February 15, 2021, 01:17:02 PM »
Thatís exactly it, itís a brain puzzle. Something I never realized how much I needed during this lockdown.

iainpunk

Re: First time designing a PCB
« Reply #25 on: February 15, 2021, 03:39:59 PM »
Quote
I know its probably old hat to most of you, but considering I am not a technically inclined guy I am pretty happy that I went from breadboard to PCB printing with in a few days.
that's super fast, i always get stuck on the breadboard stage, and rarely move further, only if i need a certain pedal or if it has very few components.

cheers, Iain

OiMcCoy

Re: First time designing a PCB
« Reply #26 on: February 15, 2021, 03:44:25 PM »
To be fair, I am still on the breadboard stage. But its just a values change choice. My goal is to have it finalized by the time I get the PCBs.

Big Monk

Re: First time designing a PCB
« Reply #27 on: February 16, 2021, 09:39:15 AM »
Its from the standard library. Omeg PC16UB Vertical. I believe in the Pot THT section.

I got to say this is a lot of fun. I am probably biting off more than I can chew but I just laid of the schematic for a Big Muff with a mid control.

It is a lot of fun, can become an addictive activity unto itself, i liken it to doing crossword puzzles.
dave



Iíve found it to be a really fun thing to do. I usually do all rough draft work in DIYLC and then manually route the PCB in Diptrace. Itís always thrilling to be pulling datasheets and getting spacing correct and then see what the final board will look like.
« Last Edit: February 16, 2021, 01:01:44 PM by Big Monk »

OiMcCoy

Re: First time designing a PCB
« Reply #28 on: February 16, 2021, 10:03:33 AM »
Trying my best to do a modded big muff, but man is this one proving to be a challenge. Trying to get it on a 1590b sized board. It's a hot mess!

OiMcCoy

Re: First time designing a PCB
« Reply #29 on: February 16, 2021, 12:30:15 PM »
I am too embarrassed to show off the complete BMP pcb. However, I decided to revisit the first project and apply what I have learned. I am way happier with this layout.


Big Monk

Re: First time designing a PCB
« Reply #30 on: February 16, 2021, 01:09:29 PM »
Trying my best to do a modded big muff, but man is this one proving to be a challenge. Trying to get it on a 1590b sized board. It's a hot mess!

Attached is an image of my recent Tone Bender MKII Layout. As you can see, this is a very tight board going into a 125B enclosure. My design constraint was an aesthetic one and in an effort to get most of the components in line, and also because I am using the larger 10 mm Vishay/Dale metal film resistors, I went through a few iterations.



I can't imagine doing a BMP in a small space but my limited experience tells me these suggestions may help:

1.) Depending on board dimensions, you may want to entertain 1/8W resistors;
2.) You'll need the smallest caps you can find

Marcos - Munky

Re: First time designing a PCB
« Reply #31 on: February 16, 2021, 01:58:37 PM »
A Big Muff in a 1590B is very doable. I have one in a 1590A, but I really can't remember if I drew the layout by myself or used somebody's layout. Probably the later. Anyway. For a 1590B layout with onboard pots, you can just google for effectslayouts big muff, but using a already made layout can take out some of the fun on doing your own.

One of the challenging parts on creating some layouts are the choices we make for our layouts. Specific in/out/v+/gnd pads position, onboard pots, aesthetic details like symmetry and parts distribution, no jumpers allowed if possible... A layout where you can put one pad for a pot on a corner of the board and another pad at the opposite corner is easier than putting those pads together at a random-ish position, and the later is easier than putting the pads on a specific position to use onboard pots.

Just three things on the MacDrive layout:
1- the pads for the transistors are too close to each other. This can easily results on them being hard to solder without any shorts.
2- you can improve the led track if you rotate R1 and C1, putting them horizontally and running the track under them. You'll have a better tracing route, but will remove the symmetry you created for the resistors (3 on each side). It's up to you what to do, but anyway I'd just at least run this track a bit far from C' and R1 pads, the trace is almost touching them.
3- the same can be said on the track that connects R1 and C1 to that bigger pad (input, probably), it's almost touching the ground pad. Put it a bit closer to R6 lower pad, but not close enough for it to touch R6 lower pad.

Btw, double sided layout?

OiMcCoy

Re: First time designing a PCB
« Reply #32 on: February 16, 2021, 04:04:55 PM »
A Big Muff in a 1590B is very doable. I have one in a 1590A, but I really can't remember if I drew the layout by myself or used somebody's layout. Probably the later. Anyway. For a 1590B layout with onboard pots, you can just google for effectslayouts big muff, but using a already made layout can take out some of the fun on doing your own.

One of the challenging parts on creating some layouts are the choices we make for our layouts. Specific in/out/v+/gnd pads position, onboard pots, aesthetic details like symmetry and parts distribution, no jumpers allowed if possible... A layout where you can put one pad for a pot on a corner of the board and another pad at the opposite corner is easier than putting those pads together at a random-ish position, and the later is easier than putting the pads on a specific position to use onboard pots.

Just three things on the MacDrive layout:
1- the pads for the transistors are too close to each other. This can easily results on them being hard to solder without any shorts.
2- you can improve the led track if you rotate R1 and C1, putting them horizontally and running the track under them. You'll have a better tracing route, but will remove the symmetry you created for the resistors (3 on each side). It's up to you what to do, but anyway I'd just at least run this track a bit far from C' and R1 pads, the trace is almost touching them.
3- the same can be said on the track that connects R1 and C1 to that bigger pad (input, probably), it's almost touching the ground pad. Put it a bit closer to R6 lower pad, but not close enough for it to touch R6 lower pad.

Btw, double sided layout?

Thanks for the great response. It is a double sided pcb. I have the ground and 9v running on the bottom layer.

I fixed up a lot of what you pointed out. An easy solution was to swap the IN and LED pads.

And thanks for pointing out the legs of the transistor being close. I will have to be careful when soldering them on the PCBs prototypes I ordered.

I have said it before and I will say it again, thank you everyone for being so incredibly helpful. I think I would be swearing at my computer and then giving up if it weren't for you.

Also, I found out there is a 3D render option.



davent

Re: First time designing a PCB
« Reply #33 on: February 16, 2021, 05:14:47 PM »
You're in deep now, there's no looking back.
dave

OiMcCoy

Re: First time designing a PCB
« Reply #34 on: February 16, 2021, 05:48:38 PM »
There for sure is no going back. I kinda want to go through a list of all the classic small circuits and design PCBs for them. Once I get confident in it, I should offer out my services to others. I mean, until I can go back to work, I have a lot of time on my hands.

Also I noticed that PCB manufacturers charge by the square inch. So I reduced the size of the OC1 Drive.



Marcos - Munky

Re: First time designing a PCB
« Reply #35 on: February 17, 2021, 07:45:51 AM »
An easy solution was to swap the IN and LED pads.
Yep, sometimes this kind of thing solves some stuff. I like to put the in pad on the lower right corner with a gnd pad right next to it, the out pad on the lower right corner with a gnd pad right next to it, or both in and out pads as close as possible (again with gnd pads right next to it). Gnd pads right next to in/out pads makes wiring way easier if you're using shielded wires. Power pads on the exact middle of the top side of the board, and usually don't care too much on the led resistor. But if this positions make me have too much work, I just use what makes the tracing easier and call it a day lol. The very board I'm building now have the output wire soldered directly to the colume pot because it was a long (and with jumpers) way to get a trace from the pot position to the out pad position I usually like to use.

Your boards are nice looking, with parts well distributed along board space. You probably can go with a bit smaller resistors, if you bend their legs as close as possible to their body they'll need a bit less of space. Or use standing resistors when space is an issue. Of course, those are just suggestions. So far, things are looking good.

OiMcCoy

Re: First time designing a PCB
« Reply #36 on: February 17, 2021, 09:18:59 AM »
An easy solution was to swap the IN and LED pads.
Yep, sometimes this kind of thing solves some stuff. I like to put the in pad on the lower right corner with a gnd pad right next to it, the out pad on the lower right corner with a gnd pad right next to it, or both in and out pads as close as possible (again with gnd pads right next to it). Gnd pads right next to in/out pads makes wiring way easier if you're using shielded wires. Power pads on the exact middle of the top side of the board, and usually don't care too much on the led resistor. But if this positions make me have too much work, I just use what makes the tracing easier and call it a day lol. The very board I'm building now have the output wire soldered directly to the colume pot because it was a long (and with jumpers) way to get a trace from the pot position to the out pad position I usually like to use.

Your boards are nice looking, with parts well distributed along board space. You probably can go with a bit smaller resistors, if you bend their legs as close as possible to their body they'll need a bit less of space. Or use standing resistors when space is an issue. Of course, those are just suggestions. So far, things are looking good.

Thanks.  I thought about doing standing resistors, but that limits the caps as my only trace jumps. I think it will come down to the enclosure limits if I choose to really make it compact.

OiMcCoy

Re: First time designing a PCB
« Reply #37 on: February 17, 2021, 11:26:03 AM »
One Knob Fuzz from Colorsound. (no pop or polarity protection)



I think I am just going to make PCB layouts for a bunch of classic circuits. Since I live in Canada, and our access to PCBs can be limited, maybe there would be a market here for PCBs. I don't know, just trying to think of ways to capitalize on my new found obsession.

rockola

Re: First time designing a PCB
« Reply #38 on: February 18, 2021, 01:45:10 AM »
Also I noticed that PCB manufacturers charge by the square inch.

Oshpark does. Most of the usual suspects in China charge the same up to 100mm x 100mm.

By-the-square-inch is very good for stuff like this.


Fancy Lime

Re: First time designing a PCB
« Reply #39 on: February 19, 2021, 12:08:55 AM »
OiMcCoy, where did you find the 3D rendering?  Is that a plug-in? I can only render the board but not the components.

Cheers,
Andy