Show Posts
Pages: [1]
1  Using Arduino / General Electronics / Re: does a Tip122 have a issolated heatsink? on: May 17, 2013, 11:45:42 pm
@ sonnyyu,

SOLD !   I'm SO picking up some of those

still have the current prob but thanks again for the part #  smiley-grin
2  Using Arduino / General Electronics / Re: does a Tip122 have a issolated heatsink? on: May 17, 2013, 11:41:40 pm
Yha, that was my best guess,   after going through 5-6 datasheets, I finally found one that actually noted it, thnz.

It's being used to drive 10M of RGB strip lights (common anode), So combining all the Collectors together is out of the question >.< ,So now how to Isolate them.

on my next trip to the store I'll be grabbing some insulated washers, but for this project I'm not using pre-tapped holes. rather than drilling and tapping them,I have some of this tape handy and Spark fun says this tape is good for 50-psi.

In this case are you concerned with adhesion, application, or heat dissipation?
3  Using Arduino / General Electronics / Re: does a Tip122 have a issolated heatsink? on: May 17, 2013, 10:24:39 pm
Has anyone used this?

https://www.sparkfun.com/products/9771
4  Using Arduino / General Electronics / does a Tip122 have a issolated heatsink? on: May 17, 2013, 08:59:11 pm
Hey there,

I'm trying to condense three tip 122's, from 3 individual heat sinks, to a larger heat stink with pipes and whatnot... (old xbox 360 GPU cooler).   I'm trying to find a data sheet that tells me if the case is active, with no luck.

      Can i attach 3 TIP122's  Directly to a single heat sink, or Must I use a MICA sheet to insulate the case's from each-other?

Either way does anyone know a good tut for isolating T220 components?

Thanks in advance.
5  Using Arduino / General Electronics / Driving a 1W star with a L317 on: January 18, 2013, 12:29:18 am
Hey guys,

I've been using Arduino for a bit now and LOVE screwing around with flashing lights  smiley-eek

***i need to run a 1W star on a dimmer, and was thinking of using the L317 adjustable voltage regulator and a (X)ohm pot.***

I will generaly use PWM and a TIP122 to drive each channel of a 3W star LED   ( using 10K pull down resistor at the gate,  100ohm current limit for the MCU,  and a 2W-10ohm current limit for the led {5v > 3v@350 ma(ish) right?}  )

BUT i want somthing CHEEP & EASY for a single LED

I would like to regulate AND adjust both voltage and current with the L317 but i can't find the right fomula ( or maby make sence of it  lol)

OR

will i have to regulate it @ 5V, use a curent limiting resistor, and adjust the voltage with a pot?

Any reasonably simple solutions i overlooked would allso be apreciated. smiley-grin
Pages: [1]