Related log: klog24157
We measured DAC noise by using ADC and whitening filters, which has already been on IXV rack.
We disconnected the cable between DAC to coil driver and connected DAC output directly to whitening filter input.
Then, whitening filter output is connected to ADC and measured the spectra with the same whitening configurations as in IY (FM1+FM2 ON: +36dB in all frequency band).
Fig1-4 shows the results.
We measured with several situations (suspension was always SAFE, but we tried to measure with master swith open, or set offset 3 cnts, 800 cnts while taing care not saturates).
In all cases we can say measured DAC noise level is 3e-4 cnt/rtHz, which is corresponding to 9.15e-8 V/rtHz (3e-4 cnt/rtHz ✕ 3.05e-4 V/cnt = 9.15e-8 V/rtHz).
This value seems to be small compared to the theoretical limit of DAC noise (~1uV/rtHz ?) as in IY (?)
HW: calculate theoretical limit of DAC noise (16 bit, 64 kHz sampling)