TMS320F28379D: CLB working frequency

Hello,

LIU LIU said:

The EPWM highest working frequency is 200MHz

Can you tell me where you found this info? I checked the datasheet and some of our other resources, and all I could find was that the ePWM's maximum frequency for the F2837xD device is 100 MHz.

LIU LIU said:

So how can I config the CLB to guarantee the CLB module(100MHz) can process the input signal from EPWM？ Or if the signal timing width is smaller than CLB timing period, CLB cannot deal with this situation？

Generally if you're trying to route in a specific signal, I recommend following the CLB Input Selection section of the CLB chapter in the technical reference manual. This section describes what filters/synchronization configurations are needed for different signals that are being used as CLB inputs. Generally, if the signal is changing faster than the CLB Tile clock, these changes will be missed (but this would essentially be passing in a 200 MHz clock signal into the CLB), there is no configuration I know of within the CLB to account for this.

LIU LIU said:

Also from Table26-2 I find CLB has local input from  ECAP/CPU outputs which working frequency may be 200MHz? How can I config the CLB for these input signal?

What I said before applies here too; if you're passing something like a 200 MHz clock signal into the CLB Tile the Tile will not be able to see every change that's happening at 200 MHz. However, keep in mind that signals from the eCAP or other peripherals don't necessarily toggle at this rate, so it may or may not affect the CLB Tile logic depending on what sort of signal you're passing through (essentially any pulse that is less than 10 ns). You can think of this as undersampling a signal, if that makes sense.

The reason for the lowered max CLB Tile frequency as compared to other peripherals comes from the fact that the CLB Tile logic goes through many paths for inputs/logic.

Best regards,

Omer Amir