RGB LED Strip doesnt turn off analogWrite(0) with MOSFET and PWM

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nibelungen
 
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RGB LED Strip doesnt turn off analogWrite(0) with MOSFET and PWM

Post by nibelungen »

Hey,

i set up a projekt with the following tutorial http://www.ladyada.net/products/rgbledstrip/
I used exactly the components.

If i set up an sketch with the following in loop

Code: Select all

analogWrite(REDPIN, 0);
        analogWrite(GREENPIN, 0);
        analogWrite(BLUEPIN, 0);
all colors should turn off - shouldnt it?!
So currently all colors are powered - not as much as with a value of 255 but they did not disapear.

Any hints to solve this?? As Powersupply i use 1,5Ampere 12V DC power supply.

Thanks in advance!!

-andreas
Gate Source and Drain i have checked and everything is okay.

All the setup i have taken from the tutorial mentioned above. (same pins etc.)

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adafruit_support_bill
 
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Re: RGB LED Strip doesnt turn off analogWrite(0) with MOSFET and PWM

Post by adafruit_support_bill »

Did you connect the power supply ground to the Arduino ground?

nibelungen
 
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Joined: Tue Sep 25, 2012 12:12 pm

Re: RGB LED Strip doesnt turn off analogWrite(0) with MOSFET and PWM

Post by nibelungen »

adafruit_support wrote:Did you connect the power supply ground to the Arduino ground?
Wow - thanks for the fast reply.

To give the strip more power i´ve set it up this way (please dont mind LED colors - maybe i switched them...)

http://imageshack.us/photo/my-images/600/rgbled.png

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adafruit_support_bill
 
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Re: RGB LED Strip doesnt turn off analogWrite(0) with MOSFET and PWM

Post by adafruit_support_bill »

Were the strips and MOSFETS purchased from Adafruit?

nibelungen
 
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Joined: Tue Sep 25, 2012 12:12 pm

Re: RGB LED Strip doesnt turn off analogWrite(0) with MOSFET and PWM

Post by nibelungen »

To be honest, no.
Shipping to germany always followed by toll and get too expensive, sadly...
Are there so much difference in the strips? The mosfets are exactly the ones adafruit suggested.

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adafruit_support_bill
 
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Re: RGB LED Strip doesnt turn off analogWrite(0) with MOSFET and PWM

Post by adafruit_support_bill »

There are many similar-but-different strips out there from many manufacturers. We can only support the products that we sell.

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kewakl
 
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Re: RGB LED Strip doesnt turn off analogWrite(0) with MOSFET and PWM

Post by kewakl »

in your image, your RGB are all off by one pin!
Only the R is on a PWM output.
Maybe a typo or wrong pick from *fritzing* library, but your FETs indicate P-channel instead on N-channel.

please verify your circuit and provided image
Gate Source and Drain i have checked and everything is okay.
All the setup i have taken from the tutorial mentioned above. (same pins etc.)

nibelungen
 
Posts: 4
Joined: Tue Sep 25, 2012 12:12 pm

Re: RGB LED Strip doesnt turn off analogWrite(0) with MOSFET and PWM

Post by nibelungen »

Hey,

thank you for the hint - my sketch was wrong... i used PWM ports.

http://postimage.org/image/m5x3xvzrh/

I use these MOSFETS

STM.pdf

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