S5L986F01 Datasheet, PDF (22/35 Pages) Samsung semiconductor – DIGITAL SIGNAL PROCESSOR FOR CDP

S5L9286F01
DIGITAL SIGNAL PROCESSOR FOR CDP
CLV SERVO
CNTL-C, E, G1, G2, and G3 registers are selected to control the CLV (Constant Linear Velocity) servo using the
data input from MICOM. Also, the design is such that the servo control is stable when setting the speed. When
setting the speed, the /(Pw≥64) signal can be detected from the /ISTAT pin only if the CNTL-D register is first set
before the CNTL-C register is selected.
Forward
This mode rotates the spindle motor in the forward direction. The related output pin status are as follows: .
SMDP
H
SMSD
Hi-Z
SMEF
L
SMON
H
Reverse
This mode rotates the spindle motor in the reverse direction. The related output pin status are as follows:.
SMDP
L
SMSD
Hi-Z
SMEF
L
SMON
H
Speed-mode
The spindle motor is controlled roughly by speed mode when track jumping or EFM phase is unlocked.
If a period of VCO is "T", the pulse width of frame sync is 22T. In case that the signal detected from EFM signal
exceeds 22T by noise on the disc and etc., it must be removed, if not, the right frame sync can't be detected. In this
case, the pulse width of EFM signal is detected by peak hold clock and bottom hold clock. ( Peak hold clock is
XTFR/2 or XTFR/4, and bottom hold clock is XTFR/16 or XTFR/32.)
The detected value is used for synchronized frame signal. If the frame signal is less than 21T, the SMDP terminal
outputs "L", eaqul to 22T, outputs "Hi-Z", and more than 23T, ouputs "H".
If the gain signal of CNTL-W register is "L", the output of SMDP terminal is reduced up to −12dB, if it is "H", there is
no reduction.
Output condition: SMSD="Hi-Z", SMEF="L", SMON="H".
Hspeed-Mode
The rough servo mode, which moves 20,000 tracks in high speed acts between the inside and outside of the CD.
The mirror domain of track which hasn't pit is duplicated with 20KHz signal to EFM. In this case, servo action is
unstable because the peak value of mirror signal which is longer than orignal frame sync signal which is detected.
In Hspeed mode, by using the 8.4672/256MHz signal against peak hold and XTFR/16 or XTFR/32 signal against
bottom hold, the mirror component is removed, and Hspeed servo action to be stable.
he output condition is as following.
SMDP
–
SMSD
Hi-Z
SMEF
L
SMON
H
22