I have been searching the ADI Engineering Zone but could not find my specific question, so I am posting it here and hope to get some answers very soon.
I have the AD2S1210 eval board.
from this, i am able to run and confirm on waveform that the default 10KHz excitation signal is good.
I used A1,A0 pin to put this device into normal velocity mode.
i configured digital Res1/Res0 pins to be 00 (10-bit) which according to the spec, i should be able to do so because i am in normal mode.
i do not have parallel bus and SPI is too slow for 10 KHz loop, so i decided to use emulated encoder output, A, B, and NM, feeding this to C2000 eQEP module.
i am to confirmed that the max P2P of differential signal of Sine to SineLo is less than 4v. so it is all good there.
1- w/o SPI or parallel bus configuration, the spec said that the Encoder output resolution will be force encoder output resolution to be the same as digital resolution which is 10. Is it correct?
" If the AD2S1210 is configured
such that the resolution of the encoder emulation outputs is
higher than the resolution of the digital outputs, the AD2S1210
internally overrides this configuration"
2- assume the answer to #1 is true. My motor is specified to run up to max 8000 rpm, 4 pole-pair. however, our application will only run max at 500 RPM. with 10-bit resolution, how do i determine the number of encoder lines? is it 256 line in 10-bit resolution? my resolver has 3 coils (sine, cosine, and excitation) and resolver is mounted directly at back of motor. What is the correct number of encoder output line for 10-bit emulation? I am confused on why we divide by 4 to get number of 256 lines for 10-bit resolution?