CXA2542AQ
Tracking Error Amplifier
R23
R24
100k
150k
C3
C4
0.01µ 0.01µ
GND
GND
TEO
LPFI
42
41
VIN > VH L
VIN < VH H
R2
260k
R5
13k
VH
TE AMP
R16
96k
BALH
NORMAL
R14
13k
C2
12p
R3
26k
SENS1
20mV
23
VC
TGFL
R9
17k
VIN
VC
BALL
38
F
R18
15k
GAIN UP
GAIN UP
VF
R8
17k
VL
–
VIN > VL H
+
SENS
SELECTOR
–20mV VIN < VL L
VC
F I-V AMP
R13
13k
V
VIN > VH L
VIN < VH H
VC
VC
R4
6.8k
R1
260k
TGFL
NORMAL
VH
TGH
200mV
R12
96k
C1
12p
39
E
SENS2
CPU
VC
24
VIN
TGL
VE
VC
VL
VC
E I-V AMP
150mV
VIN > VL H
VIN < VL L
RE
XRST
DATA
XLT
VC
21
20
19
18
COMAND
COMAND
CONTROL
CONTROL
VC
CLK
The difference between E I-V amplifier output VE and F I-V amplifier output VF is taken and output from TEO.
The tracking error amplifier has built-in balance and gain adjustment circuits to enable software-based
automatic adjustment.
The balance adjustment is performed by varying the combined resistance value of the T-configured feedback
resistance at the E I-V amplifier.
R1 × R4
E I-V AMP feedback resistance = R1 + R4 +
RE
R2 × R5
F I-V AMP feedback resistance = R2 + R5 +
= 403kΩ
R3
Vary the combined resistance value of the E I-V amplifier's feedback resistance by using the balance
adjustment switches (BAL1 to BAL4).
The gain adjustment is performed by resistance dividing the TE AMP output by the gain adjustment switches
(TOG1 to TOG4).
The balance and gain adjustment switches are controlled with commands.
Set the cut-off frequency of the external LPF between 10Hz and 100Hz.
– 19 –
SONY [ SONY CORPORATION ]
