New Cree RGB LEDs 1mm x 1mm
jmg
Posts: 15,144
Interesting parts... that of course will need driving....
Could suit P2 DACS, or DAC plus a current amplfier/mirror ?
http://www.cree.com/News-and-Events/Cree-News/Press-Releases/2017/February/New-Cree-LEDs-Power-the-Next-Generation-of-High-Definition-Indoor-Video-Screens
http://www.cree.com/hb/c1010
Looks like a PCB pitch of ~1.2mm ?
Common Anode, so a P2 could drive up to ~60 of these with a ~ 15mA current into anode and 3:1 900mA cathode Mux ?
or a current mirror with gain could manage multi-strings of 20, anode MUX'd.
With Vf of 2.25 & 3.2 @ 15mA, the P2 might need a little GND offset, or higher Vcc, and maybe Vcc modulation on the RED drive, to lower power dissipation if direct driving.
Could suit P2 DACS, or DAC plus a current amplfier/mirror ?
http://www.cree.com/News-and-Events/Cree-News/Press-Releases/2017/February/New-Cree-LEDs-Power-the-Next-Generation-of-High-Definition-Indoor-Video-Screens
http://www.cree.com/hb/c1010
Looks like a PCB pitch of ~1.2mm ?
Common Anode, so a P2 could drive up to ~60 of these with a ~ 15mA current into anode and 3:1 900mA cathode Mux ?
or a current mirror with gain could manage multi-strings of 20, anode MUX'd.
With Vf of 2.25 & 3.2 @ 15mA, the P2 might need a little GND offset, or higher Vcc, and maybe Vcc modulation on the RED drive, to lower power dissipation if direct driving.
Comments
I asked Chip a while ago whether it would be possible to measure the current out of a pin when driving it high. The theory goes your high driving pin fet might have a resistance something like 28 ohms (like P1), so if you're sourcing 10mA that's a drop of 0.28v across that P-fet, and the P2 pin ADC should be able to measure that quite easily.
Its really just a question about pin operating modes and logic, because normally when you're taking an ADC reading you're not driving the pin, but in a high impedance state. This would take an ADC reading while driving the pin.