Some PCB design ideas for DIY LDD-L driver based builds

[Lingwendil]

Just in case anybody finds these interesting, after building some larger scale LED setups for a couple propagation and fishroom setups I've been wanting something different than the usual offerings from places like Coralux, Steve'sLED, RapidLED, etc. All of the boards you see offered for sale work for lower voltage builds (12-24 volts) just fine, but the LDD-L drivers are compact, easy to use alternatives to the LDD-H series for smaller builds, or when multiple smaller strings are required. I for one use them extensively for nano fixtures, or for filling in the extra colors on "full spectrum" types of builds, in conjunction with 21 volt laptop power supplies, ranging in size from 3 to 7 amps, which is plenty in most smaller to medium situations.

These can be jumpered to allow channels to be doubled up, to allow four or eight channels of control on the eight driver version, and eight channels of control on the sixteen channel version, with daisy chaining also possible for stacking boards as needed for larger scale configurations. All parts are through-hole, so easy enough for even a novice to solder up


Keep in mind these are sort-of a power-user board, and while they offer pretty good flexibility, they are not as of now compatible with the Bluefish mini- although with the use of a level shifter they would be, the fullsize Bluefish will work however. I have been primarily using the LDD-L with the Storm controller or the very nice 16 channel controller featured over at Ultimatereef- https://www.ultimatereef.net/threads/simple-multichannel-up-to-16-led-controller.784531/ Any controller using the PCA9685 PWM driver would be a perfect fit for a companion to this board.


I'm also working up some sketches for larger versions using the LDD-H drivers as well, but due to the larger physical size I'm not sure I'll put more than eight drivers to a single board to keep them affordable for small runs of PCBs. Suggestions are welcome.

 

[Flippers4pups]

Bump

 

[crusso1993]

Interesting!

@dantimdad may offer some input.

 

[theatrus]

Just in case anybody finds these interesting, after building some larger scale LED setups for a couple propagation and fishroom setups I've been wanting something different than the usual offerings from places like Coralux, Steve'sLED, RapidLED, etc. All of the boards you see offered for sale work for lower voltage builds (12-24 volts) just fine, but the LDD-L drivers are compact, easy to use alternatives to the LDD-H series for smaller builds, or when multiple smaller strings are required. I for one use them extensively for nano fixtures, or for filling in the extra colors on "full spectrum" types of builds, in conjunction with 21 volt laptop power supplies, ranging in size from 3 to 7 amps, which is plenty in most smaller to medium situations.

These can be jumpered to allow channels to be doubled up, to allow four or eight channels of control on the eight driver version, and eight channels of control on the sixteen channel version, with daisy chaining also possible for stacking boards as needed for larger scale configurations. All parts are through-hole, so easy enough for even a novice to solder up


Keep in mind these are sort-of a power-user board, and while they offer pretty good flexibility, they are not as of now compatible with the Bluefish mini- although with the use of a level shifter they would be, the fullsize Bluefish will work however. I have been primarily using the LDD-L with the Storm controller or the very nice 16 channel controller featured over at Ultimatereef- https://www.ultimatereef.net/threads/simple-multichannel-up-to-16-led-controller.784531/ Any controller using the PCA9685 PWM driver would be a perfect fit for a companion to this board.


I'm also working up some sketches for larger versions using the LDD-H drivers as well, but due to the larger physical size I'm not sure I'll put more than eight drivers to a single board to keep them affordable for small runs of PCBs. Suggestions are welcome.

Plenty of space to add an input buffer or level shifter

 

[Lingwendil]

Nano version too!

2/4 channels, 50mm square.

More fiddling tomorrow.

 

[theatrus]

Nano version too!

More fiddling tomorrow.

I know electrically it doesn’t make a difference but the non-45 traces are causing some amount of visual strife for me [emoji51]

Glad to see more breakout boards and adapters!

 

[Lingwendil]

I struggle internally on deciding which way to go for traces- some end up looking funky if I do short runs with 45° turns, and then I go for the free angles as it makes more sense in some situations. I considered individual 2P terminals per driver to clean up the traces a bit, but figured that a single 8P made more sense.

I also considered pin headers, but doubt most will be equipped to crimp up harnesses for them.

Are there any decent and affordable through-hole push-in terminals around? Those may be ideal...

What really does me a bit of strife is arcs- I keep having them suggested to me, but I can't ever commit to them. They just look... Wrong lol


I really like the LDD series drivers, and there's something nice about modules for doing things like this in my mind. I was surprised that there was so little out there for the LDD-L series with how compact and effective ( and reliable!) They are.

 

[theatrus]

I struggle internally on deciding which way to go for traces- some end up looking funky if I do short runs with 45° turns, and then I go for the free angles as it makes more sense in some situations. I considered individual 2P terminals per driver to clean up the traces a bit, but figured that a single 8P made more sense.

I also considered pin headers, but doubt most will be equipped to crimp up harnesses for them.

Are there any decent and affordable through-hole push-in terminals around? Those may be ideal...

What really does me a bit of strife is arcs- I keep having them suggested to me, but I can't ever commit to them. They just look... Wrong lol


I really like the LDD series drivers, and there's something nice about modules for doing things like this in my mind. I was surprised that there was so little out there for the LDD-L series with how compact and effective ( and reliable!) They are.

I like Buchanan pluggable terminal blocks. 3.5mm through hole

https://www.newark.com/c/connectors...erminal-blocks?brand=buchanan-te-connectivity

 

[Lingwendil]

Cleaned up the power trace on the nano, and taking the suggestion for jumperable pulldown resistors from Oreo5457 I worked them into the Nano version- I'm not sure the best way to add it to the larger boards- I'm thinking a big jumper block for the larger boards, or even DIP switches may not be a bad idea, as having it all at the input connector may prove a bit crowded or confusing. I could just leave them right at the resistor too... Jumpers would be easy, DIP switches would be a bit more elegant I'm thinking. I also changed some traces to 90 and 45's to appease the sensibilities of some and may do the same (at least for some of the power/output traces) on the larger boards. Also contemplating an "EZ" version of the nano and eight channel boards, that would feature onboard DC jacks for power, as well as 1/8" stereo jacks for easy installation at build time. I'm also thinking of making the "EZ" and "PRO" be the designations for the different versions, as it sounds neat and intuitive

Maybe even a six channel version with onboard level shifting for use with the Bluefish mini directly? I'm trying to think of the best way to incorporate the level shifting, as it would need to be six channel capable, and likely add an onboard 5 volt supply to support it. Trivial sounding, but there are a ton of options, mostly SMD, so I'm not sure where to go from there. Suggestions would be appreciated.

 

[theatrus]

Cleaned up the power trace on the nano, and taking the suggestion for jumperable pulldown resistors from Oreo5457 I worked them into the Nano version- I'm not sure the best way to add it to the larger boards- I'm thinking a big jumper block for the larger boards, or even DIP switches may not be a bad idea, as having it all at the input connector may prove a bit crowded or confusing. I could just leave them right at the resistor too... Jumpers would be easy, DIP switches would be a bit more elegant I'm thinking. I also changed some traces to 90 and 45's to appease the sensibilities of some and may do the same (at least for some of the power/output traces) on the larger boards. Also contemplating an "EZ" version of the nano and eight channel boards, that would feature onboard DC jacks for power, as well as 1/8" stereo jacks for easy installation at build time. I'm also thinking of making the "EZ" and "PRO" be the designations for the different versions, as it sounds neat and intuitive

Maybe even a six channel version with onboard level shifting for use with the Bluefish mini directly? I'm trying to think of the best way to incorporate the level shifting, as it would need to be six channel capable, and likely add an onboard 5 volt supply to support it. Trivial sounding, but there are a ton of options, mostly SMD, so I'm not sure where to go from there. Suggestions would be appreciated.

What about just using one jumper for all the pull downs?

 

[theatrus]

Also, look at the NCP781 for a handy high voltage linear regulator which comes in TO220

 

[Lingwendil]

I'm thinking of doing a 2x8 header for each bank of eight on the sixteen channel, and individuals on the nano and eight channel boards, I'm just finding the layout gets real crowded unless I spread the power/PWM connections out into the center of the board on the sixteen. If I do that I'll have to put the resistors at the jumper block, which makes the adjacent area congested unless I use a resistor network or SMD, which I'd rather avoid...

Hmmm.

 

[Lingwendil]

Here's the first iteration of the "EZ" Nano board, onboard DC power and 1/8" TRS (stereo) jacks, so that all one needs to do is drill corresponding holes in the panel and allow the TRS jacks to protrude slightly, and then insert power. I'll work up a drilling template too (easy peasy) to make it easy enough to use. Sure beats air-wiring things on small fixture builds!

Since this is the "EZ" version, I've left off the jumpering feature to allow it to be a very simple board, if ne wishes to parallel channels they would need to do some jumpering of their own, or go with the "Pro" version of the board.

The DC jack chosen- Kobiconn 163-179PH-EX:

https://www.mouser.com/ProductDetail/Kobiconn/163-179PH-EX?qs=Xb8IjHhkxj5l2UOaIqcGCw==


The TRS/stereo jack chosen- CUI SJ1-3533:

https://www.mouser.com/ProductDetail/CUI/SJ1-3533?qs=WyjlAZoYn50TSYIwwZxYnQ==

If anyone knows of any alternatives that may be cheaper/preferable for similar quality let me know.

 

[theatrus]

Here's the first iteration of the "EZ" Nano board, onboard DC power and 1/8" TRS (stereo) jacks, so that all one needs to do is drill corresponding holes in the panel and allow the TRS jacks to protrude slightly, and then insert power. I'll work up a drilling template too (easy peasy) to make it easy enough to use. Sure beats air-wiring things on small fixture builds!

Since this is the "EZ" version, I've left off the jumpering feature to allow it to be a very simple board, if ne wishes to parallel channels they would need to do some jumpering of their own, or go with the "Pro" version of the board.

The DC jack chosen- Kobiconn 163-179PH-EX:

https://www.mouser.com/ProductDetail/Kobiconn/163-179PH-EX?qs=Xb8IjHhkxj5l2UOaIqcGCw==


The TRS/stereo jack chosen- CUI SJ1-3533:

https://www.mouser.com/ProductDetail/CUI/SJ1-3533?qs=WyjlAZoYn50TSYIwwZxYnQ==

If anyone knows of any alternatives that may be cheaper/preferable for similar quality let me know.

I like sticking to Switchcraft for the TRS.

Adding solder jumpers to bridge PWM channels is a no cost option, or adding holes for solder jumpers.

 

[Lingwendil]

got any part number recommendations from Switchcraft? There are a dizzying amount available. Most of what I saw was SMD, and looking to do through hole.

Good suggestion on the solder jumpers, I'll think of what sounds like a good way to go. a simple additional set of holes is easy.

 

[theatrus]

got any part number recommendations from Switchcraft? There are a dizzying amount available. Most of what I saw was SMD, and looking to do through hole.

Good suggestion on the solder jumpers, I'll think of what sounds like a good way to go. a simple additional set of holes is easy.

Oh, right, through hole. I was using https://www.digikey.com/product-detail/en/35RASMT4BHNTRX/SC1488-1-ND/2754493 which is nice but surface mount.

 

[Lingwendil]

Solder blob jumpering now enabled via 0805 SMD resistor outline, will allow easy parallel channel operation-

 

[Lingwendil]

Might change over to these for the TRS jacks-

https://www.mouser.com/ProductDetail/Switchcraft/35RAPC2BHN2?qs=sGAEpiMZZMv0W4pxf2HiV3fTUvSc3cBdfxmSpR0mnhU=

I'll have to relocate the pulldown resistors though. Minor nitpick.

 

[Lingwendil]

Scratch that, these look a better fit, more narrow form factor-

Switchcraft 35RAPC2BV4
https://www.mouser.com/ProductDetail/Switchcraft/35RAPC2BV4?qs=tCUFd3%2b19IPsoYOzgrtggg==

Actually, just swapped them in, minor relocation of traces, and they are in. Easy

 

[Lingwendil]

EZ-8 board in progress, this is the one I think I'll end up using the most, as most builds that I end up doing are either six or eight channels, for simple fishroom/growout setups. Not entirely happy with the power trace arrangement from the DC jack yet. Going to incorporate a simple jumpering scheme for the last two or four channels so that the fourth input can be left off as needed, probably in the same manner as the EZ Nano. One of these boards with a simple laptop (or other 18~30 volt) power brick, a handful of Luxeon Sunplus series LEDs, and a few sections of aluminum C-channel as heatsink would be a very economical way to outfit a small fishroom rack

If you can't tell I like to post frequent updates while working, it keeps me motivated, breaks up the work, and helps pass the time

As always, suggestions are welcome.