Meanwell LDD driver: for those who want to dim to 0 using Arduino

[BBM3]

Looks Good!
I like the symmetry.

1) I would make the output trace widths minimum 76 mil or better yet 100 mil. you have plenty of room.

2) The DCIN+ traces from the "square buss" to the LDD's could be increased to 100mil. They should be minimum 76 mil.

3) You can eliminate the X8 screw terminal assuming the terminal you spec'd will handle max current. If not I would split LDD 0-2 and LDD 3-5 and use two separate power supplies. Paralleling X7 and X8 does not necessarily mean the load will be split equally.

4) I would eliminate the bottom ground plane.
There is really no need for top and bottom ground planes in this circuit.
In high frequency circuits (not this one) this can cause problems.

5) Minor, but worth consideration. You have the pull up resistors placed under the LDD's. With this configuration the LDD's will not sit flush on the board.
You may want to think about moving the resistors or LDD's. Possibly move the resistors to the bottom side of the board.

Impressive work.

-BB

 

[BBM3]

Super ignorant question, but have I got those screw terminals attached the correct way (so that the wires come from off the board)? I'm not sure which side is which from looking at the design in Eagle -- there's a little triangular arrow opposite pin 1 that points in towards the PCB in the current design. Did I get that right?

Thanks!

Here is the Datasheet for the screw terminals:

https://www.phoenixcontact.com/online/portal/us?uri=pxc-oc-itemdetailid=1751248&library=usen&pcck=P-11-01-01&tab=1

I can not tell which way the terminal openings face compared with the footprint you used but the terminal looks to be symmetrical within 0.01 mm.

The data sheet also states max current 10A in one place and 13.5A in another.
You should be fine with a single terminal for DCIN +/-.

 

[joshlawless]

Looks Good!
I like the symmetry.

Thanks!

1) I would make the output trace widths minimum 76 mil or better yet 100 mil. you have plenty of room.

Bumped to 76 mils

2) The DCIN+ traces from the "square buss" to the LDD's could be increased to 100mil. They should be minimum 76 mil.

Bumped to .086 (at .1 they start to encroach on the PWM pin a little bit)

3) You can eliminate the X8 screw terminal assuming the terminal you spec'd will handle max current. If not I would split LDD 0-2 and LDD 3-5 and use two separate power supplies. Paralleling X7 and X8 does not necessarily mean the load will be split equally.

The data sheet (linked at Mouser) indicates the following values (not sure which is relevant):
Nominal current IN 13.5 A
Nominal current, UL/CUL Use Group B 10 A
Nominal current, UL/CUL Use Group D 10 A

I gather one such terminal would be sufficient?

4) I would eliminate the bottom ground plane.
There is really no need for top and bottom ground planes in this circuit.
In high frequency circuits (not this one) this can cause problems.

From capacitance, I would guess? Is there any argument to be made that the redundancy of the dual ground planes in this low-frequency circuit offers some non-zero amount of value?

5) Minor, but worth consideration. You have the pull up resistors placed under the LDD's. With this configuration the LDD's will not sit flush on the board.
You may want to think about moving the resistors or LDD's. Possibly move the resistors to the bottom side of the board.

I planned on removably mounting the LDDs via a socket, like this one: (Mouser)

Impressive work.

-BB

Thanks again!

 

[joshlawless]

I planned on removably mounting the LDDs via a socket, like this one: (Mouser)

Which I now realize would still conflict with the resistor placement. So here they've been relocated:

 

[BBM3]

Thanks!Bumped to 76 milsBumped to .086 (at .1 they start to encroach on the PWM pin a little bit)
The data sheet (linked at Mouser) indicates the following values (not sure which is relevant):
Nominal current IN 13.5 A
Nominal current, UL/CUL Use Group B 10 A
Nominal current, UL/CUL Use Group D 10 A

I gather one such terminal would be sufficient?
From capacitance, I would guess? Is there any argument to be made that the redundancy of the dual ground planes in this low-frequency circuit offers some non-zero amount of value?I planned on removably mounting the LDDs via a socket, like this one: (Mouser)

Thanks again!

Yes those screw terminals will work with some current to spare.

Exactly regarding capacitance. Plus cross talk, ground potential, etc.
Should not be a concern with your design. Personally, I avoid using ground planes on both sides unless spec'd to be used locally.

I did not see 24 pin dip sockets in your design. You can certainly place 1206 SND resistors within the confines of a socket.
FYI, even if you cut the unused pins from a 24 DIP socket, the socket will fall on top of the pull-ups as the resistors are currently placed.

Maybe move the pull-up resistors down and left a bit to avoid the resistors crashing into the socket frame?

Looking Good!
Very nice work and well thought out.

-BB

 

[007Bond]

Hey Joshlawless, can I ask what are you using to control your 6 up board.

 

[BBM3]

OOPS you found the resistor issue as I was typing.
Good work!

 

[joshlawless]

Hey Joshlawless, can I ask what are you using to control your 6 up board.

I've asked Roberto at Reef Angel to make me some custom 16-channel dimmer expansions. I'll use two of them to control twenty-four channels of lighting split across 4 fixtures. (per this thread)

Which reminds me, I haven't paid his PayPal invoice yet. Better go do that now.

 

[joshlawless]

I did not see 24 pin dip sockets in your design. You can certainly place 1206 SND resistors within the confines of a socket.
FYI, even if you cut the unused pins from a 24 DIP socket, the socket will fall on top of the pull-ups as the resistors are currently placed.

Which would be better, do you think -- cutting unused pins off the socket, or designing the board with the sockets' pins in mind? I'm guessing having the pins there would make routing the thick LED output traces a challenge, unless, since the pins wouldn't connect to anything on the board, I could route right through them?

 

[007Bond]

Looks interesting, I'll read through it. Can I ask what you think about the 5 channel 100W multichips.

 

[joshlawless]

Looks interesting, I'll read through it. Can I ask what you think about the 5 channel 100W multichips.

They look pretty great, from a color separation and ease of assembly standpoint, but I like a bit more control over the color choice than they provide (read: am a control freak).

 

[007Bond]

I see...going to finish your thread. Oh and nice job on the 6 up board!

 

[joshlawless]

Based on all the helpful input I've received, here's version 1.3 -- hopefully ready for fabrication:

Eagle threw a few DRC errors about overlap and clearance w/r/t the DCIN+ bus, which I widened in some spots by manually drawing some wire traces. I don't think it's really a problem for two wire traces on the same NET to overlap, so I cleared those errors and generated the Gerber files anyways. If no one has any other changes to suggest, I think I'll run off 10 and see how it goes.

 

[BBM3]

I'm guessing having the pins there would make routing the thick LED output traces a challenge, unless, since the pins wouldn't connect to anything on the board, I could route right through them?

You can fit your 76 miil output traces through (obviously not comfortably between) the unused pins.
However, you need to consider the effect if someone using your design were flip the LDD 180 degrees.

I prefer fool proof. I Choose the 9 pin non-revisable configuration.

If I were designing this for myself and myself only as it stands.
I would forget the socket and solder the LDD's to the board while leaving a bit of space for the resistors.

OR...

If I wanted to share and/or produce the board for others....

Make the board a bit larger and place the resistors outside of the LDD footprints and keep the 9 pin configuration.

OR...

Move the resistors to the bottom side and keep the 9 pin configuration.

My 2 cents,

-BB

 

[BBM3]

Never mind.
Disregard my previous post. Late post on my part.

Look forward to seeing your boards!

-BB

 

[joshlawless]

It took some tinkering with the grid settings, but I fit all the resistors outside of the footprints of the LDD ICs, in case anyone wants to solder them directly to the board. I even squeezed in some better labels, and got everything symmetric. Apparently, and I didn't know this until today, I have OCD. :-/

Final final version. Probably.

 

[Eud]

I used the pin sockets and trimmed off the extra pins on my 3-way O2Surplus boards. The resistors get soldered underneath and fit under the sockets nicely.

It's great that you're getting Roberto to make you a 16 channel dimmer to interface to your Reef Angel. If I do it again I'll likely forgo the Apex controlability of mine and just buy a Coralux Storm X. Less than $100 gives 16 channels of control with 4096 steps of resolution and a nice form factor. I still may get one and sell my extra VDM.

 

[n2585722]

Joshlawless,

How much is 10 of the boards you are getting?

 

[O2Surplus]

Apparently, and I didn't know this until today, I have OCD. :-/

OCD is a commonly occurring side of EAGLE usage LOL. You'll know that you have it bad- when you openly curse yourself for not "tweaking" a PcB design "just one more time" before you send the files off to the board house. I know, I've been there. LOL

 

[nemosworld]

It took some tinkering with the grid settings, but I fit all the resistors outside of the footprints of the LDD ICs, in case anyone wants to solder them directly to the board. I even squeezed in some better labels, and got everything symmetric. Apparently, and I didn't know this until today, I have OCD. :-/

Final final version. Probably.

I think I want this board just to say I have it, I don't have a use for it yet, but I think I can come up with something, Thanks for sharing and all the time and effort that went into it.
I have the coralux storm which controls 6 channels, so this would be perfect for it.