Color-Changing Pens, LEDs

B

Bob

Guest
There are some clear plastic pens around, being given away as
premiums, They contain Red, Green and Blue LEDs that slowly
turn ON and OFF, creating amazing color combinations.

What sort of LED controls can fit into such a small space?

Thanks for any help in finding out how this is done.

Bob
rapburruss@yahoo.com
 
"Bob" <eee@nowhere.com> wrote in message
news:etGdncS_591Oq8qiXTWJkQ@comcast.com...
There are some clear plastic pens around, being given away as
premiums, They contain Red, Green and Blue LEDs that slowly
turn ON and OFF, creating amazing color combinations.

What sort of LED controls can fit into such a small space?

Thanks for any help in finding out how this is done.

Bob
rapburruss@yahoo.com
Click to expand...
If I were wanting to do that I would use a hex pack schmitt invertor and
feedback R with C down to deck but these pens probably use a small ASIC that
is made by the millions under a bit of expoy.
 
Mjolinor <mjolinor@hotmail.com> wrote:
"Bob" <eee@nowhere.com> wrote in message
news:etGdncS_591Oq8qiXTWJkQ@comcast.com...
There are some clear plastic pens around, being given away as
premiums, They contain Red, Green and Blue LEDs that slowly
turn ON and OFF, creating amazing color combinations.

What sort of LED controls can fit into such a small space?

Thanks for any help in finding out how this is done.

If I were wanting to do that I would use a hex pack schmitt invertor and
feedback R with C down to deck but these pens probably use a small ASIC that
is made by the millions under a bit of expoy.
Click to expand...
I believe that you can buy (probably only a million at a time)
a LED with integrated color changing.
All you do is supply power.

--
http://inquisitor.i.am/ | mailto:inquisitor@i.am | Ian Stirling.
---------------------------+-------------------------+--------------------------
"Looks like his brainwaves crash a little short of the beach..." - Duckman.
 
I believe that you can buy (probably only a million at a time)
a LED with integrated color changing.
All you do is supply power.
Click to expand...
Can buy one-off. Electronic Goldmine's had them for a while. See:
http://sales.goldmine-elec.com/prodinfo.asp?prodid=8661

$3.25 per. Good price if you don't need to specify how the effect looks, and
considering the cost and size of building a similar effect.

Can't imagine anything I'd want to use this for. Maybe wait until the price
goes below $1.00 and make a ball of about 25 of them, and give to the
nearest college student.
 
Ian Stirling <root@mauve.demon.co.uk> wrote in message news:<bjamdc$n9u$1$8300dec7@news.demon.co.uk>...
Garrett Mace <g.ryan@macetech.com> wrote:

I believe that you can buy (probably only a million at a time)
a LED with integrated color changing.
All you do is supply power.


Can buy one-off. Electronic Goldmine's had them for a while. See:
http://sales.goldmine-elec.com/prodinfo.asp?prodid=8661

$3.25 per. Good price if you don't need to specify how the effect looks, and
considering the cost and size of building a similar effect.

Can't imagine anything I'd want to use this for. Maybe wait until the price
goes below $1.00 and make a ball of about 25 of them, and give to the
nearest college student.

Imagine a 7 segment clock, all the colours changing at once.
Click to expand...
Easy enough, just obtain a cheap LCD car clock and replace the
backlight bulb with suitably modified LEDs (RGB) connected to a colour
changing circuit usign a PIC, like at :-
http://www.emanator.demon.co.uk/bigclive/rgb.htm
 
Bob wrote:

There are some clear plastic pens around, being given away as
premiums, They contain Red, Green and Blue LEDs that slowly
turn ON and OFF, creating amazing color combinations.

What sort of LED controls can fit into such a small space?

Thanks for any help in finding out how this is done.

Bob
rapburruss@yahoo.com
Click to expand...
As others have said, it's probably an ASIC, but you can get microcontrollers in
8 pin SMT packages that can be programmed easily to achieve this result. You
just need three PWM outputs and some code that cycles in values for the
'compare' of the PWM counter for each LED. The hardest part is getting a nice
color effect because you are dealing with human perception. If you cycle from
brown to gray to white it's not gonna look good.
 
Andre <testing_h@yahoo.com> wrote:
Ian Stirling <root@mauve.demon.co.uk> wrote in message news:<bjamdc$n9u$1$8300dec7@news.demon.co.uk>...
Garrett Mace <g.ryan@macetech.com> wrote:

I believe that you can buy (probably only a million at a time)
a LED with integrated color changing.
All you do is supply power.


Can buy one-off. Electronic Goldmine's had them for a while. See:
http://sales.goldmine-elec.com/prodinfo.asp?prodid=8661

$3.25 per. Good price if you don't need to specify how the effect looks, and
considering the cost and size of building a similar effect.

Can't imagine anything I'd want to use this for. Maybe wait until the price
goes below $1.00 and make a ball of about 25 of them, and give to the
nearest college student.

Imagine a 7 segment clock, all the colours changing at once.

Easy enough, just obtain a cheap LCD car clock and replace the
backlight bulb with suitably modified LEDs (RGB) connected to a colour
changing circuit usign a PIC, like at :-
Click to expand...
Naah, I was meaning each individual segment at once.
There's got to be a market.

--
http://inquisitor.i.am/ | mailto:inquisitor@i.am | Ian Stirling.
---------------------------+-------------------------+--------------------------
"Looks like his brainwaves crash a little short of the beach..." - Duckman.
 
Ian Stirling wrote ...
Imagine a 7 segment clock, all the colours changing at once.
Click to expand...
LED "readerboards" have been doing this on a per-pixel basis.
Red/yellow/orange/green for decades.
Now that we have blue, the full spectrum is available.
 
A E <aeisenhut@videotron.ca> wrote in message news:<3F59FDA7.55A04AA1@videotron.ca>...
Bob wrote:

There are some clear plastic pens around, being given away as
premiums, They contain Red, Green and Blue LEDs that slowly
turn ON and OFF, creating amazing color combinations.

What sort of LED controls can fit into such a small space?

Thanks for any help in finding out how this is done.

Bob
rapburruss@yahoo.com

As others have said, it's probably an ASIC, but you can get microcontrollers in
8 pin SMT packages that can be programmed easily to achieve this result. You
just need three PWM outputs and some code that cycles in values for the
'compare' of the PWM counter for each LED. The hardest part is getting a nice
color effect because you are dealing with human perception. If you cycle from
brown to gray to white it's not gonna look good.
Click to expand...
Greenweld <www.greenweld.co.uk> have some colour cycling pens for 3.95 each :)

-A
 
Garrett Mace <g.ryan@macetech.com> wrote:
I believe that you can buy (probably only a million at a time)
a LED with integrated color changing.
All you do is supply power.


Can buy one-off. Electronic Goldmine's had them for a while. See:
http://sales.goldmine-elec.com/prodinfo.asp?prodid=8661

$3.25 per. Good price if you don't need to specify how the effect looks, and
considering the cost and size of building a similar effect.
Click to expand...
I've just bought one from http://www.ultraleds.co.uk/ for a bit less.

--
http://inquisitor.i.am/ | mailto:inquisitor@i.am | Ian Stirling.
---------------------------+-------------------------+--------------------------
Paranoia: A game for the whole family, and anyone else who might be watching.
 
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