Any progress on the TM1829 (800Kbps)? I’m wondering if I need to switch to the Adafruit neopixel (modified) to test these out, but I’d rather stay with FastSPI_LED2 if it will support the TM1829 soon… Thanks (Why TM1829? I want 12V pixels with low dark current and fast PWM; the current control will be fun to play with but is not what’s pushing me this direction. Need to test then and order more in time for Halloween)
I haven’t - but mostly because i’ve been slammed with work and things outside of LEDs in life. The 1829’s are pretty high up on my list of things that i’d like to get finished - but they have a really annoying protocol - the voltage signals are inverted compared to the ws2811, for example, among other things.
ALso - I had a bastard of a time tracking down the TM1829 pixels that I do have, has availability for them increased in the past month or so?
I understand and sympathize about needing time for non-pixel parts of life - thanks for the time you DO spend. I don’t know about availability. As for TM1829, Ray Wu offers some strings and strips; I don’t know if there are any delays in ordering. I just have a few - asked him to throw a few into my last order a couple of months ago;. Now I want to test and maybe standardize on them for future orders.
I’ve been trying out some TM1829’s (800KHz version). The PWM is really fast as I wanted, and the current control works as expected. Some notes and Q’s:
(1) Can I run brighter? Maybe not; for the 12V “bullet style” pixel string, I’m not sure I should use any more than the minimum 10ma/color = 30ma/string, as that seems to be what other 12V pixels use (controlled by resistors rather than software). Thoughts?
(2) Strobe (brighter but low duty cycle) I did try 100ms “strobe” flashes at 41ma/color = 123ma/pixel and they were definitely brighter than the default current (thinking of using this for lightning effects with low duty cycle). The high current strobe effect works, tho I don’t know how far it’s safe to push (current x time).
(3) Another possible use of current control - show a single color at 30ma using the software current control, while keeping the power dissipation of the pixel down. Not sure if this should be limited to 20ma anyway by LED chip internal power dissipation (vs pixel package power limits).
BTW, I used a modified Adafruit NeoPixel library, pending the support of TM1829 pixels with this library.
Bad news on the TM1809 front. The 15 pixel string I’m testing seems to have around 90 ma dark current (6ma/pixel). This is at the default 10ma/color current setting.
To check the meter, I tried (85,85,85) which would be about 1/3 of 30ma/pixel or 10ma/pixel or 150 ma avg draw, and I measure 240ma (150ma above the 90ma dark current). Seems to check out.
Aargh! I was hoping for a three wire 12V pixel with low dark current and fast PWM. This has the latter, but is perhaps even worse on the dark current front than the 12V 2801 (four wire) pixels.