Aiming to control four 1W powerleds. on default they come with some AC-DC 300mA led-drivers, 3.3v
probably those things have some sort of current limiter onboard. i measure 290mA on each LED spot.
pic1. : the default led driver
my first setup had a 6channel relay board to put 230V on each individual led-driver. The relay coils caused strange interferance (EMF/EMI?) ghost triggering all capactive touch sensors and messing with 3.3v data wires.. I tried isolating stuff (own PSU on relay ; two isolated circuits) but nothing helped, and i abondoned that idea.
now my current setup is build on NPN transistors switching step-down-convertors (ams1118 -800mA) to get the needed 3.3v on/off the LED spots.
concern is that the spots get noticable warmer, and the current i measure on A,B,C, and D are:
~350-360 mA when turning 2 spots on. (20% above default)
~320-330 mA when turning 4 spots on.
what i also notice is that the entire circuit has voltage drops when i put all 2 or 4 spots ON.
i makes me i wonder if this is an OK practice to go with..
as the led spots are clearly trying to take more then 300mA, is there anything easy to limit the DC current back to below 300mA ? without changing voltage
probably those things have some sort of current limiter onboard. i measure 290mA on each LED spot.
pic1. : the default led driver
my first setup had a 6channel relay board to put 230V on each individual led-driver. The relay coils caused strange interferance (EMF/EMI?) ghost triggering all capactive touch sensors and messing with 3.3v data wires.. I tried isolating stuff (own PSU on relay ; two isolated circuits) but nothing helped, and i abondoned that idea.
now my current setup is build on NPN transistors switching step-down-convertors (ams1118 -800mA) to get the needed 3.3v on/off the LED spots.
concern is that the spots get noticable warmer, and the current i measure on A,B,C, and D are:
~350-360 mA when turning 2 spots on. (20% above default)
~320-330 mA when turning 4 spots on.
what i also notice is that the entire circuit has voltage drops when i put all 2 or 4 spots ON.
i makes me i wonder if this is an OK practice to go with..
as the led spots are clearly trying to take more then 300mA, is there anything easy to limit the DC current back to below 300mA ? without changing voltage
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