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Phase Shifted PWM (LPC1759)

Started by micr...@ymail.com December 17, 2010
Hi there )

I'm trying to build a phase shifted PWM controller with LPC1759.

I get full phase shifted pwm in pwm mode with PWM2, PWM4 and PWM6 in dual edge mode. PWM1 is single edge by default...

Outputs
PWM1
PWM2 (symmetric of PWM1)
PWM4
PWM6 (Symmetric of PWM4)

PWM frequency is directed by PWM0 which commands the rising edge of PWM1...
After that I tried to add delay in the symmetric outputs. And it is here that I have a serious problem.
I'm able to add delay to the falling and rising edge of PWM6 in order to avoid simultaneous "on states" between PWM6 and PWM4.
Unfortunately I can't do that in PWM2, I can only add delay in the falling edge because the falling edge of PWM1 and the rising edge of PWM2 are emitted in the same line and for that they are always coincident.

Now I'm trying in MCPWM mode.

In this mode I can use two channels (0-1) where each channel have two symmetric outputs (A-B) and I can add some delay in order to avoid simultaneous "turn on states".

Now, what I don't know is that if it is possible to add or remove some phase between the channels.

Anyone know if it is possible to do that?
I'm new at this so any help that I can get is welcome :)
Thanks and sorry for my bad English.

An Engineer's Guide to the LPC2100 Series