[chbot] PWM challenge

[Mark Atherton]

The resolution of a digital based PWM is always(?) going to be limited 
by the associated highest available clock. You may be able to use 
additional switched delays to increase resolution. AFAIK similar work 
has been done in a similar vein by various extremely high resolution 
FPGA based time-to-digital converter designs.

However in the analogue domain using a ramp generator, a voltage source 
and a comparator almost limitless resolution is available. Accuracy 
however will (likely) be limited by thermal drift etc.

What are you hoping to achieve, prey tell ??

-M


On 2/11/2024 7:37 PM, Charles Manning wrote:
> Hi All
> 
> I have an idea I'd like to bounce around to see what others think.
> 
> I want to get a high precision PWM going to drive a buck switch mode at 
> a high enough frequency.
> Using a single PWM channel limits the precision I can get.
> 
> So I was thinking: maybe there is a way I can combine two PWMs to 
> generate a single high precision signal.
> 
> For example, maybe one PWM can run at a slower frequency and provide the 
> "most significant bits "and another can run at a faster frequency and 
> provide the least significant bits" and combine them with a flip flop or 
> such.
> 
> Has anyone tried similar trickery in the past or have any other cunning 
> tricks?
> 
> Thanks
> 
> Charles
> 
> 
> _______________________________________________
> Chchrobotics mailing list Chchrobotics at lists.ourshack.com
> https://lists.ourshack.com/mailman/listinfo/chchrobotics
> Mail Archives: http://lists.ourshack.com/pipermail/chchrobotics/
> Meetings usually 3rd Monday each month. See http://kiwibots.org for venue, directions and dates.
> When replying, please edit your Subject line to reflect new subjects.