Other Parts Discussed in Thread: MSP430F6736A, EVM430-F6736
We use MSP430 to measure RMS current
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We use MSP430 to measure RMS current
Hi Marcel,
I'm sorry for the delayed response, but I've spent some time digging into this topic. Here's what I've found.
Like you observed, the return registers from the ESP430 are only updated with new values every 1 second. Unfortunately, this update rate is the fastest for the ESP430 in the MSP430FE427A. According to Section 1.2.4 in the ESP430CE1A Peripheral Modules User's Guide, the number of samples for a complete ESP430 calculation sequence is 4096 and is independent of the AFE sampling frequency (fM/SD16OSRx).
Since this may be a limitation for the customer, I'd recommend that they look at the MSP430F6736A and the EVM430-F6736 if they need to revise this design.
With regards to increasing the sampling frequency, I wouldn't recommend exceeding 1 MHz for the modulation frequency. Instead, keep this frequency at 1 MHz and decrease the OSR value to increase the sampling frequency. This is general feedback, since you don't need to increase the sampling frequency here.
Regards,
James
MSP Customer Applications
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