Bose CD-20 Service Manual page 65

CD MECHANISM IC PIN CONFIGURATION TABLES
IC 821 (CXA1782BQ) Servo Signal Processor RF Amplifier Table (continued)
Pin I / O
No.
12 I
13 O
14 I
15 I
16 O
17 I
18
19 I
20 I
21 I
22 I
23 O
24 O
25 O
26 O
27 I
28 I
29 I
30 I
31 O
32 I
33 O
34 I
35 I
36 I
37 I
38 I
39 I
Terminal
Name
TA_M Tracking amplifier negative input pin.
TA_O Tracking drive output
SL_P Sled amplifier non-inversed input.
SL_M Sled amplifier negative input pin.
SL_O Sled drive output.
ISET Setting pin for focus search, Track
jump, and sled kick current.
N C
CLK Serial data transfer clock input from
CPU. (no pull up resistance)
XLT Latch input from CPU.
(no pull up resistance)
DATA Serial data input from CPU.
(no pull up resistance)
XRST Reset input; resets at low.
(no pull up resistance)
C.OUT Track number count signal output.
SENS Outputs FZC; DFCT.TZC. gain,
balance and others according to the
command from CPU.
FOK Focus OK comparator output.
(DC voltage: 10kΩ load resistance is
connected)
CC2 Input pin for the DEFECT bottom hold
output capacitance-coupled.
CC1 DEFECT bottom hold output.
C B Connection pin for DEFECT bottom
hold capacitor.
CP Connection pin for MIRR hold
capacitor. MIRR comparator non-
inversed input.
RF_I Input pin for the RF summing amplifier
output capacitance-coupled
RF_O RF summing amplifier output. Eye
pattern check point.
RF_M RF summing amplifier inversed input.
The RF amplifier gain is determined by
the resistance connected between this
pin and RFO pin.
LD APC amplifier output.
PHD APC amplifier input.
PHD1 Rf I-V amplifier inversed input. Connect
these pins to the photo diode A+C and
B+C pins.
PHD2 RF I-V amplifier inversed input.
Connect these pins to the photo diode
A+C and B+D pins.
FE_BIAS Bias adjustment of focus error amplifier.
F F I-V and E I-V amplifier inversed input.
Connect these pins to photo diodes F
and E.
E F I-V and E I-V amplifier inversed input.
Connect these pins to photo diodes F
and E.
65
Description