CXD3018Q/R
Timing Chart 2-3
Measurement interval (approximately 3.8µs)
Reference window
(132.2kHz)
Measurement pulse
(VCKI/2)
Measurement counter
VF0 to VF7
Load
m
The relative velocity R of the disc can be expressed with the following equation.
m + 1
R =
(R: Relative velocity, m: Measurement results)
32
VF0 to VF7 is the result obtained by counting VCKI/2 pulses while the reference signal (132.2kHz) generated
from the crystal (384Fs) is high. This count is 31 when the disc is rotating at normal speed and 63 when it is
rotating at double speed (when DSPB is low).
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