• State TI Thinks Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 64 subscribers
  • Views 79 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Original question:

LP5890: Current source solution to output 80mA current capacity

LP5890: Higher current output and daisy-chaining large numbers of chips

Gregory von Richter
Prodigy 10 points
Part Number: LP5890
Other Parts Discussed in Thread: LP5891-Q1

Tool/software:

I've got an high-brightness LED video wall project that has RGBW pixels, each of the 4 LEDs drawing close to 80-100 ma peak current, 320-400ma  per pixel.  The 5890 is perfect for this, but current per LED is limited to 20ma.  Can these outputs be paralleled?  Assuming yes since they're MOSFETs, but better to check. Can use 4-5 outputs in parallel and avoid external FETs.   We have 256 pixels per panel, 12 -16 panels.

Thinking eight (8) 5890s per panel.

Second, can each panel be daisy-chained to the next?  I see there is a limitation in the datasheet of 24 chips to daisychain, so how do you build a larger wall with these?  Trying to avoid an FPGA development.

Thanks!

  • 0
    TI__Expert 3551 points

    Hi Gregory,

    Our expert will reply to you later. Thanks for your patience.

  • 0
    TI__Genius 9255 points

    Hi Richter,

    could I know the average current of RGBW of your application? 

    it seems multi-channel LED Driver is more suitable than LP5891-Q1. We have another device called Jojo Family and each LED Driver includes 48 channels, and the peak current of each channel is up to 100mA. for this device, it supports up to 511 devices in one daisy chain.

    By the way, how you calculated the eight (8) 5890a per panel? 

    BR

    Monet Xu