LED Serial Driver IC

Got a hardware problem? ask for help

LED Serial Driver IC

Postby Cynar » January 31st, 2013, 5:15 am

I'm trying to find a viable IC for a project, but all my searches are being bogged down in clutter.

I want to drive a couple of RGB LEDs via a serial type link. The annoyance is I need PWM on them and quite a few.

Effectively I need a shift register type IC with about 6 outputs with PWM. I'm not worried current wise, since I am driving it through a darlington array IC.

The best I have found so far is the TLC5940 (http://www.mouser.com/ds/2/405/slvs515c-197949.pdf) at £2.29 ea this is massively overkill output wise though at 16.

Does anyone know anything more cost effective?
Cynar
 
Posts: 13
Joined: April 21st, 2012, 6:08 am

Re: LED Serial Driver IC

Postby thor17 » February 9th, 2013, 12:10 pm

Well, I don't know, what exactly you want to do...but you said, you are using darlington arrays (instead of MOSFETs what I'd prefer), so I guess your project is some kind of a fun project so you want to use inexpensive parts.
Why don't you use just shift registers? A 74HC595 does cost only something around 10cents. If you want to drive just a small LED matrix or something like this, you can drive the LEDs directly with the shift registers (using a resistor to limit the maximum current of course). You can make a software PWM.
The TLC5940 is good, but do you really need a 16-Bit PWM? Another good IC for driving LEDs is the HT1632C, it can drive up to 384 LEDs. Each output does support a 4-Bit PWM.
User avatar
thor17
 
Posts: 18
Joined: February 9th, 2013, 9:54 am

Re: LED Serial Driver IC

Postby st2000 » February 10th, 2013, 10:22 am

Found this chip:
http://auschristmaslighting.com/wiki_source/images/b/ba/WS2811.pdf
On the back of this assembly:
http://www.adafruit.com/index.php?main_page=popup_image_additional&pID=1060&pic=2&products_image_large_additional=images/large/1060quattro_LRG.jpg
Looks like you can buy that assembly here:
http://www.adafruit.com/products/1060
Don't know if they will sell you just the chip.

-good luck

@thor17, That's a cool chip (HT1632C). I'm going to cross post it to this thread (but I think the guy is going to go with individual LED controls / not a matrix):
http://forums.hackaday.com/viewtopic.php?f=2&t=3057
st2000
 
Posts: 1281
Joined: February 3rd, 2011, 6:10 pm


Return to Help me! Hardware

Who is online

Users browsing this forum: Yahoo [Bot] and 1 guest