Rslv Resolver ADC sampling synchronization

[nizhang]

Hello Guys 

Recently I am studying NXP application note AN3943, RSLV resolver driver application note. 

There is one point that I am not quite understand: 

How to synchronize the ADC trigger signal that can make sure the ADC samples at the peak point of the resolver analog reference signal? 

From the diagram (Figure 9), I can see there are resolver digital reference and resolver analog reference (this should be the excitation signal). So in my understanding, the resolver digital reference is generated by the eTPU PWM function, so what is the relationship between the resolver digital reference and resolver analog reference? I am a little bit confused about that. How to configure this PWM output and the ADC trigger PWM from the eTPU to make sure the synchronization?

I attached both screenshots of the diagram. 

Thanks a lot for your help 

Ni 

[davidtosenovjan]

Hi, there is a hardware interface in between like this:

AN3943 references AN1942/D describing Resolver theory and hardware interface as well:

https://www.nxp.com/docs/en/application-note/AN1942.pdf 

Hope it helps

[nizhang]

Hi, these info helps, thanks a lot