Replacement/alternative LEDs, online stores, specs, etc?

[-Tj-]

I'm interested in adding LEDs to the two empty pads on the Pandora's board or swapping out the existing ones for different colors, but the only LEDs I'm familiar with are the Radio Shack hobby-type ones that have the plastic "bulb" and two or three long metal leads coming from them (made for breadboards?). I'm starting this thread to ask for help on stuff like what kind of LEDs are used on on the Pandora, what specifications I should be looking for to add or replace LEDs, where I can buy them, how much they typically go for, colors, what resistors and FETs to use, and so on. I'm also interested to know more about the keypad backlight (KP BL) solder pads. It's likely I won't use it for any kind of keyboard backlighting since the keymat is black, but I'm sure I could find some other creative use for it. I read MWeston's hacking guide, but I couldn't really make out what I needed. I'm looking for a more "Pandora Hacking for Dummies" approach.


Questions:


- What kind of LEDs are used in the Pandora?


- Is there a specific name for the types of LEDs used?

- What colors?


- What voltage?


- What size?

- How much do they usually cost per?

- Where can such LEDs be purchased?

- What other colors can be found?

- Which of those can be used in the Pandora?

- Single color, multicolor, which pads can use/make use of either?

- What is an FET? (please be especially kind here, I looked it up, and it still made no sense)


- What kind of resistors and FETs need to be used when adding LEDs?

- Where can such resistors and FETs be purchased?

- Are there certain limitations on the LEDs when used on the Pandora?

- I had read recently that only a couple LEDs have brightness control, while the rest are on/off. Can the others be configured to have brightness values as well, or is this a firmwarae and/or hardware thing?

Sorry about the weird formatting. This is about as close as I could get it to the way it looked in my head. Also, I hope this hasn't been asked before in great lengths because I searched and couldn't find what I was looking for. Perhaps my search-fu isn't strong enough.

 

[gotwake424]

As far as led colors go you can get an LED in an SMD package in pretty much any color ( red, green, blue,white,yellow?).


I can tell you that you can activate these led's with really simple calls- the guys on pandora irc helped me out with that.


As far as im concerned/not using a FET the KP/BL pads for the backlight would be the easiest to use.


Check out:


www.mouser.com


www.digikey.com


If you want solder the led's directly to the pads you need to go the SMD package. If you are not experienced at soldering I wouldn't recommend trying to get both the led and resistor on there.


Good luck-Hope that answered some questions


Blake

 

[-Tj-]

Thanks, I had a look at the two sites and there's a lot to look at on both. They're a lot cheaper than I thought they'd be, but I hope I'm looking at the right ones for the info. Soldering directly to the pads is the option I'm going for.


So far as not using a FET, is that just for the KP BL pads? Reason asking about the FET and resistors and such was because I came across one post from MWeston telling ED he needed to add those when adding LEDs to the LED7 and LED8 pads. No further specifics were made in that thread, which is why this thread exists.


Still looking for more answers regarding the other things, like resistor and FET information especially. After waiting so long to get my Pandora (and still waiting lol) I wouldn't want to fry board components by not using the right parts.

 

[gotwake424]

Well FET are used as a transistor to turn them on and off.


The KP BL pads do not need them, so they would be the easiest to use as they can be turned on and off from the cl.


Maybe MWeston might be able to clarify this better

 

[Letalis Sonus]

As far as I can tell the difference between FETs and 'common' Transistors is simply that a FET only needs voltage on its triggering line, there is no current flow. This way the triggering line is totally independent, so you can e.g. use them to control something with higher voltage and lots of amperes using the weak low voltage output of a micro controller.

 

[Binky]

Why are these led pads not populated in the factory?


Would a custom order (with these LEDs soldered in manually) be possible?

 

[gotwake424]

Why are these led pads not populated in the factory?


Would a custom order (with these LEDs soldered in manually) be possible?

because the keypad is solid black

 

[-Tj-]

Why are these led pads not populated in the factory?


Would a custom order (with these LEDs soldered in manually) be possible?

To add to what gotwake424 mentioned, the LED7 and LED8 pads can apparently have LEDs soldered to them by ED, but the thread I found where someone requested that was also the one that triggered this thread. MWeston chimed in there to say that LEDs can't just be added, resistors and FETs also have to be added. Thus, I'm not sure if ED ever did solder LEDs to that person's board.


Edit: MWeston's quote from that thread:

Yes. I got red and green LEDs here.

That won't work. You'd also have to add the resistors and FETs.

Also, thanks for the answers, guys. Please keep them coming.

 

[Neelix]

Have you checked out the Hardware Hacking wiki page? Page 4 of the Official Hackers Manual, linked from that page may help here.


- Neelix

 

[-Tj-]

Have you checked out the Hardware Hacking wiki page? Page 4 of the Official Hackers Manual, linked from that page may help here.


- Neelix

Yup, that's one of the first places I looked, but so far as I could tell it just says where you need to add stuff, not what you need to add if you want to use them. That info is also in MWeston's hacking guide, but all the information shown in both places seem to assume you already know what you're doing.

 

[dgame]

Here you go:


http://www.gp32x.de...04-moar-leds-p/


shopping list in post #4

 

[Binky]

Here you go:


http://www.gp32x.de...04-moar-leds-p/


shopping list in post #4

My soldering skills aren't up to it :mellow: especially not on a rare £400 board.


Might ask ED if he could add them to my unit before he sends it (at a fee ^_^ ) there's gotta be a use for more indicator lights...