Re: Color Kinetics Controller

["Ian Davidson" <ian@xxxxxxx>]

Hi Frank

The opto is an option. I had looked but thought against it for now. The
lights each have a 33k resistor in series with the i/p and a 10K resistor pulldown to 0V from the i/p. So each time a light is added to the chain it<= BR> adds another 43k resistance to 0V. I think I'm going to use a PNP drive
transistor driven by NPN pulling the PNP base low. The NPN can then be
driven straight from the uP. It should work out at about =A31.50 for the transistor bits. The board is a stand alone powered of the same PSU as the<= BR> lights so isolation at this time is not needed. I think to be on the safe side when I add the rs232 control an Opto to the serial side of things is a=
must, just to prevent any damage to PC MB if wired incorrectly. I have foun= d
some transistors with the correct spec but if you have used any suggestions=
of devices with turn-on & off times in the 10's of nS then please let m= e
have the numbers.

Thanks Frank

Ian D


----- Original Message -----
From: "Frank Mc Alinden" <armagh@xxxxxxx>
To: <ukha_d@xxxxxxx>
Sent: Sunday, October 13, 2002 10:12 AM
Subject: Re: [ukha_d] Color Kinetics Controller


> Hi Ian
>            = ; Just a thought could you not use a high speed opto to do the
> switching then you could use +5v control ??? Depends how many you need= as
> they cost around $8.00 each..
>
> Frank Mc
> ----- Original Message -----
> From: "Ian Davidson" <ian@xxxxxxx>
> To: "HA Yahoo group UK" <ukha_d@xxxxxxx>
> Sent: Sunday, October 13, 2002 6:58 PM
> Subject: [ukha_d] Color Kinetics Controller
>
>
> > Hi All
> >
> > OK. The controller has not moved far yet. I have a very basic wor= king
unit
> but to test it I modified one of the lights to accept 0 to 5V switchin= g.
The
> last thing anyone wants is to take all there lights apart and swap som= e
> surface mount components. So I'm currently sorting out the electronics= to
> control unmodified units. They need high speed switching transistors. = The
> data pulses are 4 micro seconds in length and need to switch to +24V.<= BR> > Standard general purpose transistors have switch on/off times of a few=
> microseconds and do not work. If I don't have any suitable transistors=
I'll
> order some tomorrow and try them out Tuesday night. I should get a cou= ple
of
> hours tonight so I'll try to do some more work on the software. I just=
> thought I would keep people informed as I've been to busy over these l= ast
> few days to post.
> >
> > Ian D
> >
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> > http://www.automatedho= me.co.uk
> > Post message: ukha_d@xxxxxxx > > Subscribe:  ukha_d-subscribe@xxxxxxx > > Unsubscribe:  ukha_d-unsubscribe@xxxxxxx > > List owner:  ukha_d-owner@xxxxxxx > >
> > List of UKHA Groups here -
http://groups.ya= hoo.com/group/UKHA_Grouplists/
> >
> > Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/te= rms/
> >
> >
> >
>
>
>
> http://www.automatedhome.co= .uk
> Post message: ukha_d@xxxxxxx > Subscribe:  ukha_d-subscribe@xxxxxxx > Unsubscribe:  ukha_d-unsubscribe@xxxxxxx > List owner:  ukha_d-owner@xxxxxxx >
> List of UKHA Groups here - http://groups.yahoo.com/group/UKHA_Grouplists/
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>

Yahoo! Groups Spons= or

ADVERTISEMENT

http://www.automatedhome.co.uk 
Post message: ukha_d@xxxxxxx 
Subscribe:  ukha_d-subscribe@xxxxxxx 
Unsubscribe:  ukha_d-unsubscribe@xxxxxxx 
List owner:  ukha_d-owner@xxxxxxx
List of UKHA Groups here - http://groups.yahoo.com/group/UKHA_Grouplists/

Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.