EHRPWM functions of AM3358 are running with 100 MHz. Thus the smallest possible half pulse width is 10 nsec (10 nsec of and 10 nsec on for a full period).
Am Sonntag, 5. Oktober 2014 00:53:06 UTC+2 schrieb Bill Gray: > > So, I've been playing around with PWM, and I would like to have one PWM > channel drive a buck circuit and another channel drive a boost circuit. > > The magnetics that I am looking to use would like to be driven in the > 100-150khz range. Mosfets to drive this are not a dime a dozen, but > perhaps $10/dozen. > > I've read other places that the PWMs can have a base frequency as high as > 1.6Mhz? > > Currently I'm using P9_14 to drive the input of an oscilloscope which is > 1Mohm-15pf and the wave form looks like slow capacitor charging. When I > model the slope on spice it looks like the output impedance of P9_14 might > be in the 50-70kOhm range? > > This means that I can't create a crisp pwm signal at any where near the > frequency I'm hoping for. > > Also, this would mean that the maximum current out of a pin at 3.3v would > be 0.06mA... and that has got to be wrong as I have seen too many warnings > to limit source/sink current to 6mA or less??? > > Any ideas what I might be doing wrong that is limiting my pwm max > frequency so badly? > > Thanks, > > Bill > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
