Suggestions for LED Driver, SPI and PWM output?

[Jay Dee]

Hi Guys,
I've had a quick trawl in the usual places... Im looking for a multi channel LED driver chip, that provides individual PWM outputs and controlled by SPI.
Most of the chips I have found are i2C but I'd prefer SPI as I use the SPI for the CAN module.
A 16 channel chip with individual 8 bit PWM on each output would allow complete RGB and brightness control of 4 Leds
Thanks for any pointers. J.

[Benj]

Hello,

A quick Google search came up with the following. No idea on pricing.

http://www.national.com/pf/LP/LP55281.html#Overview

It may be cheaper to use say a PIC in SPI slave mode and do the PWM via a timer interrupt.

[Benj]

Found the part on Digikey, however the IC is a ball grid array. How are your SMD skills?

This could be another option.

http://hackaday.com/2009/06/29/parts-sh ... ule-a6281/

I used this text for my Google search.

SPI RGB LED Driver

[Jay Dee]

Cheers Ben,
I'll have a look at those when I get to get out of this damn airport and to the hotel.
I did do a google search on much the same terms (honest ) but most datasheets seem to be for devices running I2C or some alternative form of serial....and I want to stick to a standard (flowcode supported) serial comms for now and SPI is preferred as I'm using in other commonly used blocks. I'll have a good 'ol read up and see how the idea develops.
Thanks, J.

[JAW]

Hello Jay Dee,

Have you looked at the TLC5940 made by Texas Instruments? 16 CHANNEL LED DRIVER WITH DOT CORRECTION AND GRAYSCALE PWM CONTROL. Available on eBay.

Regards

JAW

[Jay Dee]

Thanks JAW, its quite a beestie. Reasonable price £2-3 from farnell and not in BGA. I've saved the datasheet and will have a proper look through later. I'd love to look more at my LED project but its just finding time...hmm.