pwm npn mosftet and rgb led with common cathode

Hello guys, I'm an electronics newbie and I have lots of doubts about project that I'm slowly doing a lamp with RGB LED.

I have led with common cathode and three anode (rgb), everything works perfectly connecting each anode to a PWM output, problems arise when I want to light so many LEDs, using an 'external power supply. I bought mosfet P10NK60ZFP (datasheet n channel. I know that the LEDs, I know that I should buy the LEDs with an anode and three cathodes so as to control them easily. Unfortunately, I bought 100 LEDs with common cathode, so I have to overcome? I can reverse the tension with an auxiliary circuit? I also have the tlc5940nt that I can not use for the same reason! I have to throw the led or have any hope? I could solve a driving pnp moftet using my npn mosfet, it might work or is it crazy?

Thanks to all

Firstly MOSFETs are n-channel or p-channel (sometimes called NMOS and PMOS), 'PNP' and 'NPN' are bipolar transistors.

Back to the question - how are you proposing running these LEDS - all in parallel? You would need a much better spec'd MOSFET for that, the only you link too is a high voltage device (with high Ron). For low voltage switching go for a MOSFET with 50 milliohm or lower Ron.

A p-channel MOSFET might solve your problem - think about reflecting your circuit top-for-bottom - all the positive and negatives swap over.

If your supply is more than 5V you'll have to interface to the MOSFET with a transistor. If the supply is 5V choose a logic-level MOSFET (the Ron will be specified at 4.5V as well as 10V for a logic-level device).

By the way the MOSFET you mention is not a logic-level device. It requires 10V to drive the gate. Don't be confused by the 'threshold' voltage spec - this is not the voltage it turns on at, its the voltage it starts to conduct miniscule currents. Logic level devices have thresholds about 1V or so.

thanks for your clarification about the names of the mosfet. yes,i want use the leds in parallel, so i can't use my mosfet togheter with new p channel mosfet ? do you can recommend me mosfet type ?