Light Pipes...

R

Ricketty C

Guest
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

It sure seems all the light pipe makers like the right angle designs. I guess most calls for light pipes are from boards with their own front panel attached to the board edge rather than the board being mounted parallel to the panel. I suppose there is also the small box design with the board in the bottom again perpendicular to the front panel on the end of the case.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209
 
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!
Click to expand...

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.
 
On Sat, 22 Aug 2020 20:16:11 -0700 (PDT), Ricketty C
<gnuarm.deletethisbit@gmail.com> wrote:

Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

It sure seems all the light pipe makers like the right angle designs. I guess most calls for light pipes are from boards with their own front panel attached to the board edge rather than the board being mounted parallel to the panel. I suppose there is also the small box design with the board in the bottom again perpendicular to the front panel on the end of the case.
Click to expand...

These Bivars are nice.

https://www.dropbox.com/s/mwi030deeufxxrs/PLP2-XXX-880372.pdf?dl=0

https://www.dropbox.com/s/z78x7fc0uk1jjyu/P900_Front_M.jpg?raw=1

https://www.dropbox.com/s/lleigwv9jrazw2k/P900_Top_1.jpg?raw=1

https://www.dropbox.com/s/9k574r88sy76g8q/J270_Light_Pipes.jpg?raw=1

They look nice and create a wide viewing angle. They press into the
panel. They would work with the board parallel or perpendicular to the
panel.








--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard
 
On 2020-08-23, Edward Lee <edward.ming.lee@gmail.com> wrote:
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.
Click to expand...

Filament printers leave voids, and the voids will be dispersive, but
if the path of the print head follows the path you want the lighte to
take it might work like an optic fibre.

Having the guide cut from a sheet of acrylic might be a better bet but
that limits you to two dimensions.

If you must print you may need to use a resin printer to get
satisfactory results.

--
Jasen.
 
On Saturday, August 22, 2020 at 11:40:32 PM UTC-4, Edward Lee wrote:
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.
Click to expand...

I think that would produce a fairly poor light pipe. They work by total internal reflection and very smooth surfaces. I don\'t think 3D printing can create surfaces anywhere near smooth enough and the light would be rather scattered about even with the reflective coating.

But thanks for the idea.

I can get three color LEDs in smaller packages that will work with some of the light pipes I can find, but then I need 30 drivers for them all. The LED I want to use has a driver chip built in that is loaded serially and they can all be daisy chained requiring only one pin! But it\'s larger. Might be able to use one that spaces the pipes at 5.08 mm by skipping every other pipe. This still fits on the board if we need 9 indicators. But the space under the pipe is not quite wide enough to center the LED package. Some room is required to prevent interference. I guess the question is how much. I\'ve always used 10 mils (0.25 mm), but I know parts float around on the pads. I guess 10 mils is more of a pad to pad spacing.

I\'ve found two manufacturers who make the chip on board RGB LED. They both use the same protocol. But pumping the data out to all the LEDs over a single pipe is a bit tedious for the CPU having to time 1200 ns bits to 80 nS resolution for some quarter of a millisecond might be a problem when interrupts need to do something important.

I don\'t get why the protocol can\'t be interrupted for a while. They are timing the bit high time, but maybe they are using the bit cycle time to calibrate the time reference. No, that doesn\'t really make sense. Anyway, there are two bit timing cycles and a reset is no data for 50us. So if the bit low time were interrupted for a significantly less time than 50 us, it seems the bit transmission could resume. I suppose a USART or SPI port could be used to push out bit patterns with less involvement from the CPU than bit banging. The timing is based on quarters of the bit time, so an 8 bit byte shifted out at the correct speed would send 2 data bits. Likely the entire sequence can be shifted out using DMA.

--

Rick C.

+ Get 1,000 miles of free Supercharging
+ Tesla referral code - https://ts.la/richard11209
 
On Sunday, August 23, 2020 at 12:36:30 AM UTC-4, jla...@highlandsniptechnology.com wrote:
On Sat, 22 Aug 2020 20:16:11 -0700 (PDT), Ricketty C
gnuarm.deletethisbit@gmail.com> wrote:

Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

It sure seems all the light pipe makers like the right angle designs. I guess most calls for light pipes are from boards with their own front panel attached to the board edge rather than the board being mounted parallel to the panel. I suppose there is also the small box design with the board in the bottom again perpendicular to the front panel on the end of the case.

These Bivars are nice.

https://www.dropbox.com/s/mwi030deeufxxrs/PLP2-XXX-880372.pdf?dl=0

https://www.dropbox.com/s/z78x7fc0uk1jjyu/P900_Front_M.jpg?raw=1

https://www.dropbox.com/s/lleigwv9jrazw2k/P900_Top_1.jpg?raw=1

https://www.dropbox.com/s/9k574r88sy76g8q/J270_Light_Pipes.jpg?raw=1

They look nice and create a wide viewing angle. They press into the
panel. They would work with the board parallel or perpendicular to the
panel.
Click to expand...

Nice thought, but we can\'t put any holes in the front panel overlay. It is a sheet of plastic which is part of the outer shell to allow thorough cleaning of the device. But that, like much of this box, is likely to be rethought by the manufacturer who picks this up. Even though the entire front panel is one unpenetrated surface, the edges are not sealed, large openings for plumbing, etc.

So the light pipes need to be surface mounted with a length around 14 and 15 mm. There is a 16x2 char LCD that is setting that dimension. The length is not so much a problem. I\'ve found some of those. The issue is they don\'t leave room for the RGB, \"built in IC\" LED I want to use so I only need a single I/O pin rather than 30. It might not need to be 30, but it will be at least 20 more driver pins.

--

Rick C.

-- Get 1,000 miles of free Supercharging
-- Tesla referral code - https://ts.la/richard11209
 
On Sunday, August 23, 2020 at 1:30:51 AM UTC-4, Jasen Betts wrote:
On 2020-08-23, Edward Lee <edward.ming.lee@gmail.com> wrote:
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.

Filament printers leave voids, and the voids will be dispersive, but
if the path of the print head follows the path you want the lighte to
take it might work like an optic fibre.

Having the guide cut from a sheet of acrylic might be a better bet but
that limits you to two dimensions.

If you must print you may need to use a resin printer to get
satisfactory results.
Click to expand...

Interesting thoughts. They have some laser cut acrylic parts they use now. It seems like a PITA to laser cut custom light pipes. They would need to heat polish the cut sides too. Not sure how to mount them. I suppose we could use through hole fasteners, those things they call bolts! The ready made units have compliant press fit pins. I don\'t think we could make those. Maybe a square pin could be left and a die used to cut a thread on it.

--

Rick C.

-+ Get 1,000 miles of free Supercharging
-+ Tesla referral code - https://ts.la/richard11209
 
On Saturday, August 22, 2020 at 11:17:40 PM UTC-7, Ricketty C wrote:
On Saturday, August 22, 2020 at 11:40:32 PM UTC-4, Edward Lee wrote:
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.
I think that would produce a fairly poor light pipe. They work by total internal reflection and very smooth surfaces. I don\'t think 3D printing can create surfaces anywhere near smooth enough and the light would be rather scattered about even with reflective coating.
Click to expand...

You can smooth out the surface with wet sanding, then buff is out with alcohol based solution. I have seen video of finished product that look like moulded parts, rather than 3D printed. With external metallic paint, they are good mirrors.
 
søndag den 23. august 2020 kl. 08.17.40 UTC+2 skrev Ricketty C:
On Saturday, August 22, 2020 at 11:40:32 PM UTC-4, Edward Lee wrote:
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.

I think that would produce a fairly poor light pipe. They work by total internal reflection and very smooth surfaces. I don\'t think 3D printing can create surfaces anywhere near smooth enough and the light would be rather scattered about even with the reflective coating.

But thanks for the idea.

I can get three color LEDs in smaller packages that will work with some of the light pipes I can find, but then I need 30 drivers for them all. The LED I want to use has a driver chip built in that is loaded serially and they can all be daisy chained requiring only one pin! But it\'s larger. Might be able to use one that spaces the pipes at 5.08 mm by skipping every other pipe. This still fits on the board if we need 9 indicators. But the space under the pipe is not quite wide enough to center the LED package. Some room is required to prevent interference. I guess the question is how much. I\'ve always used 10 mils (0.25 mm), but I know parts float around on the pads. I guess 10 mils is more of a pad to pad spacing.

I\'ve found two manufacturers who make the chip on board RGB LED. They both use the same protocol. But pumping the data out to all the LEDs over a single pipe is a bit tedious for the CPU having to time 1200 ns bits to 80 nS resolution for some quarter of a millisecond might be a problem when interrupts need to do something important.

I don\'t get why the protocol can\'t be interrupted for a while. They are timing the bit high time, but maybe they are using the bit cycle time to calibrate the time reference. No, that doesn\'t really make sense. Anyway, there are two bit timing cycles and a reset is no data for 50us. So if the bit low time were interrupted for a significantly less time than 50 us, it seems the bit transmission could resume. I suppose a USART or SPI port could be used to push out bit patterns with less involvement from the CPU than bit banging. The timing is based on quarters of the bit time, so an 8 bit byte shifted out at the correct speed would send 2 data bits. Likely the entire sequence can be shifted out using DMA.
Click to expand...

https://wp.josh.com/2014/05/13/ws2812-neopixels-are-not-so-finicky-once-you-get-to-know-them/ ?
 
On Sunday, August 23, 2020 at 3:10:03 AM UTC-4, Edward Lee wrote:
On Saturday, August 22, 2020 at 11:17:40 PM UTC-7, Ricketty C wrote:
On Saturday, August 22, 2020 at 11:40:32 PM UTC-4, Edward Lee wrote:
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.
I think that would produce a fairly poor light pipe. They work by total internal reflection and very smooth surfaces. I don\'t think 3D printing can create surfaces anywhere near smooth enough and the light would be rather scattered about even with reflective coating.

You can smooth out the surface with wet sanding, then buff is out with alcohol based solution. I have seen video of finished product that look like moulded parts, rather than 3D printed. With external metallic paint, they are good mirrors.
Click to expand...

I guess you could do that, but we need a commercial product. They want this to be built in large quantities.

--

Rick C.

+- Get 1,000 miles of free Supercharging
+- Tesla referral code - https://ts.la/richard11209
 
On Sunday, August 23, 2020 at 4:57:02 AM UTC-4, Lasse Langwadt Christensen wrote:
søndag den 23. august 2020 kl. 08.17.40 UTC+2 skrev Ricketty C:
On Saturday, August 22, 2020 at 11:40:32 PM UTC-4, Edward Lee wrote:
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.

I think that would produce a fairly poor light pipe. They work by total internal reflection and very smooth surfaces. I don\'t think 3D printing can create surfaces anywhere near smooth enough and the light would be rather scattered about even with the reflective coating.

But thanks for the idea.

I can get three color LEDs in smaller packages that will work with some of the light pipes I can find, but then I need 30 drivers for them all. The LED I want to use has a driver chip built in that is loaded serially and they can all be daisy chained requiring only one pin! But it\'s larger. Might be able to use one that spaces the pipes at 5.08 mm by skipping every other pipe. This still fits on the board if we need 9 indicators. But the space under the pipe is not quite wide enough to center the LED package. Some room is required to prevent interference. I guess the question is how much. I\'ve always used 10 mils (0.25 mm), but I know parts float around on the pads. I guess 10 mils is more of a pad to pad spacing.

I\'ve found two manufacturers who make the chip on board RGB LED. They both use the same protocol. But pumping the data out to all the LEDs over a single pipe is a bit tedious for the CPU having to time 1200 ns bits to 80 nS resolution for some quarter of a millisecond might be a problem when interrupts need to do something important.

I don\'t get why the protocol can\'t be interrupted for a while. They are timing the bit high time, but maybe they are using the bit cycle time to calibrate the time reference. No, that doesn\'t really make sense. Anyway, there are two bit timing cycles and a reset is no data for 50us. So if the bit low time were interrupted for a significantly less time than 50 us, it seems the bit transmission could resume. I suppose a USART or SPI port could be used to push out bit patterns with less involvement from the CPU than bit banging. The timing is based on quarters of the bit time, so an 8 bit byte shifted out at the correct speed would send 2 data bits. Likely the entire sequence can be shifted out using DMA.


https://wp.josh.com/2014/05/13/ws2812-neopixels-are-not-so-finicky-once-you-get-to-know-them/ ?
Click to expand...

Interesting. These are a different manufacturer, Worldsemi vs. Kingbright and Lumex who seem to be interchangable. The WS2812B from Worldsemi has slightly different timing specs with tighter tolerances, but for what this guy was showing is that the tolerances are just data sheet numbers.

The other two brands are sold through distribution and are much lower in price when dealing with quantities.

You seem to always find pertinent and interesting links. Is it your google-foo or have you worked with this before?

--

Rick C.

++ Get 1,000 miles of free Supercharging
++ Tesla referral code - https://ts.la/richard11209
 
On 2020-08-23, Ricketty C <gnuarm.deletethisbit@gmail.com> wrote:
On Sunday, August 23, 2020 at 12:36:30 AM UTC-4, jla...@highlandsniptechnology.com wrote:
On Sat, 22 Aug 2020 20:16:11 -0700 (PDT), Ricketty C
gnuarm.deletethisbit@gmail.com> wrote:

Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

It sure seems all the light pipe makers like the right angle designs. I guess most calls for light pipes are from boards with their own front panel attached to the board edge rather than the board being mounted parallel to the panel. I suppose there is also the small box design with the board in the bottom again perpendicular to the front panel on the end of the case.

These Bivars are nice.

https://www.dropbox.com/s/mwi030deeufxxrs/PLP2-XXX-880372.pdf?dl=0

https://www.dropbox.com/s/z78x7fc0uk1jjyu/P900_Front_M.jpg?raw=1

https://www.dropbox.com/s/lleigwv9jrazw2k/P900_Top_1.jpg?raw=1

https://www.dropbox.com/s/9k574r88sy76g8q/J270_Light_Pipes.jpg?raw=1

They look nice and create a wide viewing angle. They press into the
panel. They would work with the board parallel or perpendicular to the
panel.

So the light pipes need to be surface mounted with a length around 14 and 15 mm. There is a 16x2 char LCD that is setting that dimension. The length is not so much a problem. I\'ve found some of those. The issue is they don\'t leave room for the RGB, \"built in IC\" LED I want to use so I only need a single I/O pin rather than 30. It might not need to be 30, but it will be at least 20 more driver pins.
Click to expand...

A:

Raise the neopixels closer to the panel. (use a daughter board
suported by the connectors)

B:

LP5030 needs two pins (fewer if you already have an IIC bus)



--
Jasen.
 
On 2020-08-23, Ricketty C <gnuarm.deletethisbit@gmail.com> wrote:
On Sunday, August 23, 2020 at 1:30:51 AM UTC-4, Jasen Betts wrote:
On 2020-08-23, Edward Lee <edward.ming.lee@gmail.com> wrote:
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.

Filament printers leave voids, and the voids will be dispersive, but
if the path of the print head follows the path you want the lighte to
take it might work like an optic fibre.

Having the guide cut from a sheet of acrylic might be a better bet but
that limits you to two dimensions.

If you must print you may need to use a resin printer to get
satisfactory results.

Interesting thoughts. They have some laser cut acrylic parts they use now. It seems like a PITA to laser cut custom light pipes. They would need to heat polish the cut sides too. Not sure how to mount them. I suppose we could use through hole fasteners, those things they call bolts! The ready made units have compliant press fit pins. I don\'t think we could make those. Maybe a square pin could be left and a die used to cut a thread on it.
Click to expand...

Or cut hooks that go through holes or slots in the PCB.


O=acrylic or polycarbonate

|###|
|###|
| |
| |
OOOOOOOOOOOOOOOOOOOOOOOOOOO
OO###| O
O###| O
|###|NNNNNNN O
|###|NNNNNNN O
|###|NNNNNNN-_ OOOOOOOOOOOOOOOOOOOO
|###|NNNNNNN \\ OOOOOOOOOOOOOOOOOOOO
|###|NNNNNNN \\ OOOOOOOOOOOOOOOOOOO
|###|NNNNNNN |OOOOOOOOOOOOOOOOOOO
|###|NNNNNNN |OOOOOOOOOOOOOOOOOOO
|###|NNNNNNN / OOOOOOOOOOOOOOOOOOO
|###|NNNNNNN _/ OOOOOOOOOOOOOOOOOOOO
|###|NNNNNNN- OOOOOOOOOOOOOOOOOOOO
|###|NNNNNNN O
|###|NNNNNNN O
O###| O
OO###| O
OOOOOOOOOOOOOOOOOOOOOOOOOOO
| |
| |
|###| NOT TO SCALE
|###|


--
Jasen.
 
søndag den 23. august 2020 kl. 18.56.18 UTC+2 skrev Ricketty C:
On Sunday, August 23, 2020 at 4:57:02 AM UTC-4, Lasse Langwadt Christensen wrote:
søndag den 23. august 2020 kl. 08.17.40 UTC+2 skrev Ricketty C:
On Saturday, August 22, 2020 at 11:40:32 PM UTC-4, Edward Lee wrote:
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.

I think that would produce a fairly poor light pipe. They work by total internal reflection and very smooth surfaces. I don\'t think 3D printing can create surfaces anywhere near smooth enough and the light would be rather scattered about even with the reflective coating.

But thanks for the idea.

I can get three color LEDs in smaller packages that will work with some of the light pipes I can find, but then I need 30 drivers for them all. The LED I want to use has a driver chip built in that is loaded serially and they can all be daisy chained requiring only one pin! But it\'s larger. Might be able to use one that spaces the pipes at 5.08 mm by skipping every other pipe. This still fits on the board if we need 9 indicators. But the space under the pipe is not quite wide enough to center the LED package. Some room is required to prevent interference. I guess the question is how much. I\'ve always used 10 mils (0.25 mm), but I know parts float around on the pads. I guess 10 mils is more of a pad to pad spacing.

I\'ve found two manufacturers who make the chip on board RGB LED. They both use the same protocol. But pumping the data out to all the LEDs over a single pipe is a bit tedious for the CPU having to time 1200 ns bits to 80 nS resolution for some quarter of a millisecond might be a problem when interrupts need to do something important.

I don\'t get why the protocol can\'t be interrupted for a while. They are timing the bit high time, but maybe they are using the bit cycle time to calibrate the time reference. No, that doesn\'t really make sense. Anyway, there are two bit timing cycles and a reset is no data for 50us. So if the bit low time were interrupted for a significantly less time than 50 us, it seems the bit transmission could resume. I suppose a USART or SPI port could be used to push out bit patterns with less involvement from the CPU than bit banging. The timing is based on quarters of the bit time, so an 8 bit byte shifted out at the correct speed would send 2 data bits. Likely the entire sequence can be shifted out using DMA.


https://wp.josh.com/2014/05/13/ws2812-neopixels-are-not-so-finicky-once-you-get-to-know-them/ ?

Interesting. These are a different manufacturer, Worldsemi vs. Kingbright and Lumex who seem to be interchangable. The WS2812B from Worldsemi has slightly different timing specs with tighter tolerances, but for what this guy was showing is that the tolerances are just data sheet numbers.

The other two brands are sold through distribution and are much lower in price when dealing with quantities.

You seem to always find pertinent and interesting links. Is it your google-foo or have you worked with this before?
Click to expand...

mostly google-foo, I looked at using them some time ago but never got around
to it
 
On Monday, August 24, 2020 at 12:15:27 PM UTC-4, Lasse Langwadt Christensen wrote:
søndag den 23. august 2020 kl. 18.56.18 UTC+2 skrev Ricketty C:
On Sunday, August 23, 2020 at 4:57:02 AM UTC-4, Lasse Langwadt Christensen wrote:
søndag den 23. august 2020 kl. 08.17.40 UTC+2 skrev Ricketty C:
On Saturday, August 22, 2020 at 11:40:32 PM UTC-4, Edward Lee wrote:
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.

I think that would produce a fairly poor light pipe. They work by total internal reflection and very smooth surfaces. I don\'t think 3D printing can create surfaces anywhere near smooth enough and the light would be rather scattered about even with the reflective coating.

But thanks for the idea.

I can get three color LEDs in smaller packages that will work with some of the light pipes I can find, but then I need 30 drivers for them all.. The LED I want to use has a driver chip built in that is loaded serially and they can all be daisy chained requiring only one pin! But it\'s larger.. Might be able to use one that spaces the pipes at 5.08 mm by skipping every other pipe. This still fits on the board if we need 9 indicators. But the space under the pipe is not quite wide enough to center the LED package. Some room is required to prevent interference. I guess the question is how much. I\'ve always used 10 mils (0.25 mm), but I know parts float around on the pads. I guess 10 mils is more of a pad to pad spacing.

I\'ve found two manufacturers who make the chip on board RGB LED. They both use the same protocol. But pumping the data out to all the LEDs over a single pipe is a bit tedious for the CPU having to time 1200 ns bits to 80 nS resolution for some quarter of a millisecond might be a problem when interrupts need to do something important.

I don\'t get why the protocol can\'t be interrupted for a while. They are timing the bit high time, but maybe they are using the bit cycle time to calibrate the time reference. No, that doesn\'t really make sense. Anyway, there are two bit timing cycles and a reset is no data for 50us. So if the bit low time were interrupted for a significantly less time than 50 us, it seems the bit transmission could resume. I suppose a USART or SPI port could be used to push out bit patterns with less involvement from the CPU than bit banging. The timing is based on quarters of the bit time, so an 8 bit byte shifted out at the correct speed would send 2 data bits. Likely the entire sequence can be shifted out using DMA.


https://wp.josh.com/2014/05/13/ws2812-neopixels-are-not-so-finicky-once-you-get-to-know-them/ ?

Interesting. These are a different manufacturer, Worldsemi vs. Kingbright and Lumex who seem to be interchangable. The WS2812B from Worldsemi has slightly different timing specs with tighter tolerances, but for what this guy was showing is that the tolerances are just data sheet numbers.

The other two brands are sold through distribution and are much lower in price when dealing with quantities.

You seem to always find pertinent and interesting links. Is it your google-foo or have you worked with this before?


mostly google-foo, I looked at using them some time ago but never got around
to it
Click to expand...

I\'d really like to use them for this project. Needing just one line to drive 30 LEDs is a big advantage without using extra chips. I just need to pipe the light to the front panel a half inch away.

I can use this light pipe, but the chip will need to be enough off center to allow for manufacturing tolerances and soldering movement. At some point that will impact the optical connection to the light pipe.

Anyone know what to expect for component misalignment? The part is 5x5 mm with six pads on two sides, not QFN, more like a J lead.

--

Rick C.

--- Get 1,000 miles of free Supercharging
--- Tesla referral code - https://ts.la/richard11209
 
On Monday, August 24, 2020 at 2:58:54 PM UTC-4, Ricketty C wrote:
On Monday, August 24, 2020 at 12:15:27 PM UTC-4, Lasse Langwadt Christensen wrote:
søndag den 23. august 2020 kl. 18.56.18 UTC+2 skrev Ricketty C:
On Sunday, August 23, 2020 at 4:57:02 AM UTC-4, Lasse Langwadt Christensen wrote:
søndag den 23. august 2020 kl. 08.17.40 UTC+2 skrev Ricketty C:
On Saturday, August 22, 2020 at 11:40:32 PM UTC-4, Edward Lee wrote:
On Saturday, August 22, 2020 at 8:16:17 PM UTC-7, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

I haven\'t done it yet, but was thinking about 3D printing some clear custom pattern. You can just design what you need with clear filament, then cover the outside with metallic paint.

I think that would produce a fairly poor light pipe. They work by total internal reflection and very smooth surfaces. I don\'t think 3D printing can create surfaces anywhere near smooth enough and the light would be rather scattered about even with the reflective coating.

But thanks for the idea.

I can get three color LEDs in smaller packages that will work with some of the light pipes I can find, but then I need 30 drivers for them all. The LED I want to use has a driver chip built in that is loaded serially and they can all be daisy chained requiring only one pin! But it\'s larger. Might be able to use one that spaces the pipes at 5.08 mm by skipping every other pipe. This still fits on the board if we need 9 indicators. But the space under the pipe is not quite wide enough to center the LED package. Some room is required to prevent interference. I guess the question is how much. I\'ve always used 10 mils (0.25 mm), but I know parts float around on the pads. I guess 10 mils is more of a pad to pad spacing.

I\'ve found two manufacturers who make the chip on board RGB LED. They both use the same protocol. But pumping the data out to all the LEDs over a single pipe is a bit tedious for the CPU having to time 1200 ns bits to 80 nS resolution for some quarter of a millisecond might be a problem when interrupts need to do something important.

I don\'t get why the protocol can\'t be interrupted for a while. They are timing the bit high time, but maybe they are using the bit cycle time to calibrate the time reference. No, that doesn\'t really make sense. Anyway, there are two bit timing cycles and a reset is no data for 50us. So if the bit low time were interrupted for a significantly less time than 50 us, it seems the bit transmission could resume. I suppose a USART or SPI port could be used to push out bit patterns with less involvement from the CPU than bit banging. The timing is based on quarters of the bit time, so an 8 bit byte shifted out at the correct speed would send 2 data bits. Likely the entire sequence can be shifted out using DMA.


https://wp.josh.com/2014/05/13/ws2812-neopixels-are-not-so-finicky-once-you-get-to-know-them/ ?

Interesting. These are a different manufacturer, Worldsemi vs. Kingbright and Lumex who seem to be interchangable. The WS2812B from Worldsemi has slightly different timing specs with tighter tolerances, but for what this guy was showing is that the tolerances are just data sheet numbers.

The other two brands are sold through distribution and are much lower in price when dealing with quantities.

You seem to always find pertinent and interesting links. Is it your google-foo or have you worked with this before?


mostly google-foo, I looked at using them some time ago but never got around
to it

I\'d really like to use them for this project. Needing just one line to drive 30 LEDs is a big advantage without using extra chips. I just need to pipe the light to the front panel a half inch away.

I can use this light pipe, but the chip will need to be enough off center to allow for manufacturing tolerances and soldering movement. At some point that will impact the optical connection to the light pipe.

Anyone know what to expect for component misalignment? The part is 5x5 mm with six pads on two sides, not QFN, more like a J lead.
Click to expand...

It is looking less likely I will need the 5x5 LED with the built in driver. I was mistaken and most of the LED positions only need a single color with one needing two and two others needing three colors. So that is only 13 I/Os. Since we are adding an FPGA to handle the alarm conditions we will have enough I/Os I\'m pretty sure. I might need to roll an ADC converter to directly measure analog inputs. That or add a multiple input ADC.

I was surprised to learn they use musical notes for audible alarms. That will be fun to do in the FPGA.

--

Rick C.

--+ Get 1,000 miles of free Supercharging
--+ Tesla referral code - https://ts.la/richard11209
 
On Sunday, 23 August 2020 at 13:16:17 UTC+10, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

It sure seems all the light pipe makers like the right angle designs. I guess most calls for light pipes are from boards with their own front panel attached to the board edge rather than the board being mounted parallel to the panel. I suppose there is also the small box design with the board in the bottom again perpendicular to the front panel on the end of the case.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209
Click to expand...

https://www.mentor.de.com/bauelemente/en/portfolio-2/portfolio-lightguides/

Element14 (Newark in the US?) have a subset of their range available.

Importing from EU to US if you see soemthing not available locally may be a bit time consuming ...
--
Cheers,
Chris.
 
On Tue, 25 Aug 2020 19:04:55 -0700 (PDT), Chris <chris.863@live.com>
wrote:

On Sunday, 23 August 2020 at 13:16:17 UTC+10, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

It sure seems all the light pipe makers like the right angle designs. I guess most calls for light pipes are from boards with their own front panel attached to the board edge rather than the board being mounted parallel to the panel. I suppose there is also the small box design with the board in the bottom again perpendicular to the front panel on the end of the case.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

https://www.mentor.de.com/bauelemente/en/portfolio-2/portfolio-lightguides/

Element14 (Newark in the US?) have a subset of their range available.

Importing from EU to US if you see soemthing not available locally may be a bit time consuming ...
Click to expand...

What\'s strange is that light pipes cost more, sometimes outrageously
more, than LEDs.



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard
 
On Tuesday, August 25, 2020 at 10:05:00 PM UTC-4, Chris wrote:
On Sunday, 23 August 2020 at 13:16:17 UTC+10, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

It sure seems all the light pipe makers like the right angle designs. I guess most calls for light pipes are from boards with their own front panel attached to the board edge rather than the board being mounted parallel to the panel. I suppose there is also the small box design with the board in the bottom again perpendicular to the front panel on the end of the case.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

https://www.mentor.de.com/bauelemente/en/portfolio-2/portfolio-lightguides/

Element14 (Newark in the US?) have a subset of their range available.

Importing from EU to US if you see soemthing not available locally may be a bit time consuming ...
Click to expand...

Those are the parts we are looking at, but they don\'t have room for the 5x5..5 mm serially configured RGB LEDs I was looking at using. We have shifted gears yet again and will be using an FPGA to control the alarms so we have a bunch more pins now and regular tricolor LEDs will fit under them fine.

We do need to enlarge the board by 1 mm though! lol. They are too close to the LCD modules. I\'d like to see the board grow by a bit more, but there\'s a flow and oxygen sensor in the way. Maybe we can get 2 mm, lol.

--

Rick C.

-+- Get 1,000 miles of free Supercharging
-+- Tesla referral code - https://ts.la/richard11209
 
On Tuesday, August 25, 2020 at 10:31:31 PM UTC-4, jla...@highlandsniptechnology.com wrote:
On Tue, 25 Aug 2020 19:04:55 -0700 (PDT), Chris <chris.863@live.com
wrote:

On Sunday, 23 August 2020 at 13:16:17 UTC+10, Ricketty C wrote:
Seem hard to find, or more accurately, it\'s hard to find a light pipe manufacturer with a decent web site where you can actually pick what you want in an intelligent way.

I need a row of LEDs spaced wider than 5 mm since the chip package is 5 mm wide. I can\'t find anyone who provides info on their parts with the dimensional data in the search. VCC is seriously bad and they don\'t actually have that many parts. I think I could create a selection guide for them that would put it all on one page!

It sure seems all the light pipe makers like the right angle designs. I guess most calls for light pipes are from boards with their own front panel attached to the board edge rather than the board being mounted parallel to the panel. I suppose there is also the small box design with the board in the bottom again perpendicular to the front panel on the end of the case.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

https://www.mentor.de.com/bauelemente/en/portfolio-2/portfolio-lightguides/

Element14 (Newark in the US?) have a subset of their range available.

Importing from EU to US if you see soemthing not available locally may be a bit time consuming ...

What\'s strange is that light pipes cost more, sometimes outrageously
more, than LEDs.
Click to expand...

Even weirder, is that they seem to cost nearly the same if they are 1 LED or up to 10 ganged LED light pipes. I guess it\'s the fact that they are using the machine and they can pretty much make as many 10 unit pipes per minute as they can 1 unit pipes.

I have no idea how these things are made optically correct... mostly. I see some units where a flat side is bowed in dramatically from the shrinking of the plastic as it what? cools? Hardens? I\'m mot even sure if they mold them with heat or make the plastic in the mold. I seem to recall the process of making acrylic is very simple and can be done in a beaker, then you break the beaker to free the plastic.

--

Rick C.

-++ Get 1,000 miles of free Supercharging
-++ Tesla referral code - https://ts.la/richard11209
 
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