IRFP360 mosfet driver

[cosminnci]

Life without Arduino still exist. 

Very true
and that is a really nice chip (LM3445)
but I need to control the dimmer via software.
I was studying if I could connect the arduino to the LM3445

[oldway]

I read your posts again and there is a lot of problems:

I am using the pwm from the atmega, the default 976hz is too small I would like 7812hz or 62500hz

Flickering at frequency of 100Hz or more is no more visible by human eyes.
What probably happens, is that PWM frequency and 100Hz of the rectified mains voltage are not sincronized and the beating of the two frequencies is producing low frequency flickering. (like aliasing in DSO)
The only solutions are feeding the led strip with filtered DC or use a phase control at 100Hz.

I use a rectifier bridge so the led strip is powered with DC

Can you do that ? It is a 220Vac led strip, what is the internal schematic of this strip ?
If you have a resistor in serie with two led's in anti-parallel, feeding with DC instead of AC, you will have only one of the two LED's working and he will have to much current (two times the nominal average current)

It was intended for AC and, in my opinion, you can't feed it with rectified AC voltage.

...is intended for use at probably under 10% that is why all the dimming and pwm needs.

Can't you feed it with a lower voltage ? 110Vac for exemple ? You could use a 110Vac dimmer.

...and that is a really nice chip (LM3445)

This chip can be used only with LED's without current limiting resistors. Can't be used with your led strip.

...but I need to control the dimmer via software.

Easy to do with a modified dimmer and an optocoupler 4N25.

[cosminnci]

Hi,

It is 1 resistor 2 leds but not in anti-parallel, when fed with rectified 220v both light up
as the chineese we bought from says:

we have 220 flexible strip
Marcello-HTDLED: but it still need a Bridge pile of line
just like a transformer

we use 220v (Europe) stepping down to 110 would be more trouble.

so far I belive I have a stable setup with 6N137 and MCP1407

I will test it in a few days and see how it works.

[oldway]

we use 220v (Europe) stepping down to 110 would be more trouble.

Why ? Use simply an ATF 220/110V. It's cheap and easy to buy.

[cosminnci]

Still it would not help much the strips are cut in length of 1m which requires 220V

[cosminnci]

I have tested my solution and the result is bad, it generates flashes and the noise is audible in the switching power supply near the circuit.
for 1m of strip it works great but when I go to 100m it starts flashing and making noise.

is it possible that the switching noise from the mosfet to go back in the mains trough the bridge rectifier ?

I am asking this because I have another smps powered from the same socket and it is whining too.