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Djgmt
07-13-2017, 01:24
Hello i got my hands on a bag of little red diodes about 50 of them and want to put all of them in to a board. but have no idea on how to wire them all up. i think there 5mw red, any help would be great ..Thanks52560

VDX
07-13-2017, 01:43
... wire them in series and drive them with constant current at higher voltage.

I have a 652nm-module with 60 (!) diodes in series, which needs 400mA and are supported with maybe 180 Volts driving voltage :cool:

My recomendation would be something like 24 or 48 Volts (common PS voltages) and a MOSFET based CC-driver.

Check the needed voltage per diode, so you can estimate the number in the chain -- e.g. 2,5V per diode and 4 Volts drop at the driver will give:

24V - 4V = 20V -or- 48V - 4V = 44V max driver voltage

20V / 2,5V = 8 diodes -or- 44V / 2,5V = 17 diodes in series ...

Viktor

Djgmt
07-13-2017, 02:33
Thanks Heeps now to have a go at it. Cheers