About EPWM BLOCK - TI C2000 DC/DC Buck Converter Example
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I have basic question about f28379d EPWM block in this example -> (https://www.mathworks.com/help/supportpkg/texasinstrumentsc2000/ug/dc-dc-buck-converter.html)
And I watched the related video about this example ---- > (https://www.youtube.com/watch?v=CstjgrGR7dY)
According to working principle of ADC , We don't make the ADC start of conversion,while pwm transitioning . For this reason ADC start of conversion launchs the conversion before the X(any time) of period.
In buck example with f28379d , and its EPWM block as following:
This is provided via CMPB value. Period is 1000. When counter is equai to CMPB value , ADC will start conversion as you can see at CMPB value.
But I didn't understand how to choose CMPB value as (15+54)/2 ? What are the mean 15 and 54 values ? Where do they come from ?
Can you explain briefly ?
回答 (1 件)
Venkatesh Chilapur 2020 年 9 月 16 日
The first factor i.e 15 is related to the ADC SOCx acquisition window. The second factor i.e 54 is time from the end of the S+H window until the ADC results latch in the ADCRESULTx register. Refer the ADC block in the model and the controller TRM for more details. Since we have 2 SOC's configured here, hence the mutiplication factor of 2.