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New Cree RGB LEDs 1mm x 1mm

jmgjmg Posts: 11,267
edited February 2017 in Propeller 2 Vote Up0Vote Down
Interesting parts... that of course will need driving....
Could suit P2 DACS, or DAC plus a current amplfier/mirror ?

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.


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  • Interesting. There are also smaller versions of the WS2812B leds (3.5mm square, eg SK6812Mini)

    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.
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