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LEDStripe mosfet

Q: Control single-light LED strip 24v with Raspberry pi and mosfet

OmriI’m trying to make my LED strip fade-in and fade-out by using Raspberry-pi 4, unfortunately for me, I am not an electronic expert. Every tutorial I saw so far was for RGB LED strips and I have a single-color(3000K) LED strip with just 2 pins (+ & -). Im have: LRS-50-24 datasheet 30N06L datasheet…ledOmri@tlfong01 I bought it at a local store, I don’t have much information about it except its 24V, 10Watt per meter and 3000K@tlfong01 I dont see the wiring diagram in that video, could you check the link? Sim Son3482@tlfong01 the gate-source threshold voltage is too high for a 3.3V logic level. Vgs,th should not be more than half the logic voltage at most, especially if you switch high currents. So my judgement is: the mosfet is not suitable and it will become hot and may fail. Omri@SimSon what kind of mosfet do you suggest to use? Sim SonAs I said, I suggest to use a MOSFET with a Vgs,th of no more than half the logic level voltage at maxOmri@SimSon good news. I replaced the MOSFET with IRLB8721 and it’s working. BUT the power of the LED lights is very weak… why is that? reminder – it is 24V LED strip with 10watt per meter Sim Sonyst 22:56Can you messure the voltage between drain and source? In case the mosfet is fully on it should be in the range of millivolts. Omri@SimSon when led turned off its 8.2V and when turned on (full bright) its 4.72V Sim SonI see, the IRLB8721 appears to be unsuitable, too. Its Vgs,th is 2.35V, but you need a mosfet with no more than 1.5V. Ideally, you want to measure 24V when the mosfet is off and 0V when it is on. Omri@SimSon what other features I should look up for when searching for the right mosfet? other than Vgs,th <= 1.5V. Any recommendations on how to search for it? Sim Son3482Well, voltage and current ratings are trivial. Next priority is Vgs,th to be as low as possible. When switching currents of more than 1A, the last thing is an on-resistance Rds,on as low as possible, as this will determine the final voltage drop (U=RI) and power dissipation (P=RI²) in the mosfet. But the most critical feature when controlling mosfets with a Pi really is Vgs,th. Search for “Logic Level MOSFETS”. Omri@SimSon I tried looking for one here digikey.com/en/products/filter/discrete-semiconductor-produc‌​ts/… but none have all features you recommended. I will really appreciate if you could help me find one or two which fits Sim Son3482yst 22:59I see, it’s not as easy to find one with Vgs,th below 1.5V as I thought. Maybe you choose one with Vgs,th<=2V. Power dissipation might be higher then, so a low Rds,on is a bit more important. IDK how much current you expect, but a MOSFET I’m often working with is the DMG3402 (Vgs,th<1.4V), but it’s an SMD mosfet. I guess you’d prefer a through-hole version… Sim Son3482yst 23:10… DMT6009LJ3 should workor IRLU024NPBFmost of those are fine (features are not always correct on the distributors’ sites):
mou.sr/2O91ISQ

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