MPC5xxx中的主题 PWM frequency for MPC5646

PWM frequency for MPC5646

phobos973 — Tue, 30 Oct 2012 15:28:41 GMT

Hi,

I read in an application note, that PWM frequencies are usually between 1KHz and 100KHz. But I also read in the DS of the MPC5646 that the peripheral frequency is in the range 8MHz-120MHz.

So what is exactly the frequency of the PWM module for the MPC5646? I need a high frequency like the peripheral frequency (more than 8MHz), is that possible?

Thank you for your help.

Regards,

Re: PWM frequency for MPC5646

lama — Wed, 31 Oct 2012 06:09:48 GMT

If you mean eMIOS PWM then eMIOS belongs to peripheral set 3 which can be clocked by frequency derived (divide from /1 to /16 (CGM_SC_DC2 Register)) from sysclk (max 120MHz). Next divider in series to previous is a global prescaler of eMIOS module (1~256). So, max input clock for PWM can be pwmclk = 120/1/1=120MHz. Now the period of the PWM signal is defined by PWM period setup for defined mode. fPWM = period / pwmclk.

Best Regards, Ladislav