pwm frecuency

[ale0502]

Hi,
I understand that the pwm frecuency must be 10KHz, but on my board I have about 3KHz.
Any idea what´s wrong?
I have an 8MHz crystal.

thanks

[Piotrsko]

Should generally be about 8khz for most power igbts today at the low end. Newer ones are faster and therefore generate less heat as a rule of thumb.

Comments: sure your measuring method works?

I could see 4 khz because you are using 1/2 the base frequency, And you should have some divisor process in the control chip.