MN662785TBUC Datasheet, PDF (27/89 Pages) Panasonic Semiconductor – LSI FOR COMPACT DISC/CD ROM PLAYER

MN662785TBUC
(C) Setting of gain crossover for optical servo loop
Before performing focus and tracking automatic adjustments, gain crossover after automatic adjustment can
be determined by writing data to the label name GSET (address: 10h) according to the table below.
In the automatic gain adjustment, disturbance is input to the servo loop, and gain is increased or decreased
according to the GSET setting after adjusting the gain so that the feedback gain at the disturbance frequency
becomes 0 dB (gain crossover is equal to the disturbance frequency).
(Setting for focus system)
Data
(D7 to D0)
Address (HEX)
(A7 to A0)
Command (HEX)
Table 7-1-4 (5)
Function (ˎ : Setting at reset)
Ì­ Ì­ Ì­ Ì­ D3 D2 D1 D0
10
Ì­Ì­Ì­Ì­ 0 1 1 1
Ì­Ì­Ì­Ì­ 0 1 1 0
Ì­Ì­Ì­Ì­ 0 1 0 1
Ì­Ì­Ì­Ì­ 0 1 0 0
Ì­Ì­Ì­Ì­ 0 0 1 1
Ì­Ì­Ì­Ì­ 0 0 1 0
Ì­Ì­Ì­Ì­ 0 0 0 1
Ì­Ì­Ì­Ì­ 0 0 0 0
Ì­Ì­Ì­Ì­ 1 1 1 1
Ì­Ì­Ì­Ì­ 1 1 1 0
Ì­Ì­Ì­Ì­ 1 1 0 1
Ì­Ì­Ì­Ì­ 1 1 0 0
Ì­Ì­Ì­Ì­ 1 0 1 1
Ì­Ì­Ì­Ì­ 1 0 1 0
Ì­Ì­Ì­Ì­ 1 0 0 1
Ì­Ì­Ì­Ì­ 1 0 0 0
F2
Focus gain at the disturbance frequency of 750 Hz
Approx. valueɿ ʵ3.92 dB
Approx. valueɿ ʵ3.36 dB
Approx. valueɿ ʵ2.80 dB
Approx. valueɿ ʵ2.24 dB
Approx. valueɿ ʵ1.68 dB
Approx. valueɿ ʵ1.12 dB
Approx. valueɿ ʵ0.56 dB
ˎ Approx. valueɿ
0 dB
Approx. valueɿ 1.05 dB
Approx. valueɿ 2.11 dB
Approx. valueɿ 3.16 dB
Approx. valueɿ 4.21 dB
Approx. valueɿ 5.27 dB
Approx. valueɿ 6.32 dB
Approx. valueɿ 7.37 dB
Approx. valueɿ 8.43 dB
(Setting for tracking system)
Data
(D7 to D0)
Address (HEX)
(A7 to A0)
Command
(HEX)
Table 7-1-4 (6)
Function (ˎ : Setting at reset)
D7 D6 D5 D4 Ì­ Ì­ Ì­ Ì­
10
0 1 1 1 Ì­Ì­Ì­Ì­
0 1 1 0 Ì­Ì­Ì­Ì­
0 1 0 1 Ì­Ì­Ì­Ì­
0 1 0 0 Ì­Ì­Ì­Ì­
0 0 1 1 Ì­Ì­Ì­Ì­
0 0 1 0 Ì­Ì­Ì­Ì­
0 0 0 1 Ì­Ì­Ì­Ì­
0 0 0 0 Ì­Ì­Ì­Ì­
1 1 1 1 Ì­Ì­Ì­Ì­
1 1 1 0 Ì­Ì­Ì­Ì­
1 1 0 1 Ì­Ì­Ì­Ì­
1 1 0 0 Ì­Ì­Ì­Ì­
1 0 1 1 Ì­Ì­Ì­Ì­
1 0 1 0 Ì­Ì­Ì­Ì­
1 0 0 1 Ì­Ì­Ì­Ì­
1 0 0 0 Ì­Ì­Ì­Ì­
F2
Tracking gain at the disturbance frequency of 1 kHz
Approx. valueɿ ʵ3.92 dB
Approx. valueɿ ʵ3.36 dB
Approx. valueɿ ʵ2.80 dB
Approx. valueɿ ʵ2.24 dB
Approx. valueɿ ʵ1.68 dB
Approx. valueɿ ʵ1.12 dB
Approx. valueɿ ʵ0.56 dB
ˎ Approx. valueɿ
0 dB
Approx. valueɿ 1.05 dB
Approx. valueɿ 2.11 dB
Approx. valueɿ 3.16 dB
Approx. valueɿ 4.21 dB
Approx. valueɿ 5.27 dB
Approx. valueɿ 6.32 dB
Approx. valueɿ 7.37 dB
Approx. valueɿ 8.43 dB
SDD00026AEM
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