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ORDER NO.
CRT3896
DVD MECHANISM MODULE(MS5)
CX-3212
- This service manual describes the operation of the DVD mechanism module incorporated in models
listed in the table below.
- When performing repairs use this manual together with the specific manual for model under repair.
Model Service manual DVD Mechanism Module
AVIC-D3/XU/UC CRT3879 CXK6601
AVIC-D3/XU/EW5
CONTENTS
1. CIRCUIT DESCRIPTIONS................................................................................................................................ 2
2. MECHANISM DESCRIPTIONS ...................................................................................................................... 19
3. DISASSEMBLY ............................................................................................................................................... 24
PIONEER CORPORATION 4-1, Meguro 1-chome, Meguro-ku, Tokyo 153-8654, Japan
PIONEER ELECTRONICS (USA) INC. P.O. Box 1760, Long Beach, CA 90801-1760, U.S.A.
PIONEER EUROPE NV Haven 1087, Keetberglaan 1, 9120 Melsele, Belgium
PIONEER ELECTRONICS ASIACENTRE PTE. LTD. 253 Alexandra Road, #04-01, Singapore 159936
PIONEER CORPORATION 2007
K-ZZU. FEB. 2007 Printed in Japan
1 2 3 4
1. CIRCUIT DESCRIPTIONS
1. Front end section (MN2DS0016AAUB : IC1501)
MN2DS0016AAUB is a 1 chip LSI for DVD-Player. A DVD-Player system can be constructed by connecting this LSI,
A driver IC, SDRAM, Flash-ROM, Audio-DAC, etc.
This LSI includes a front end (SODC/FE) which executes RF signal processing, servo processing and decode
processing, a back end (AV decoder/BE) which executes video decode processing such as MPEG1/MPEG2/JPEG
and audio decode processing such as DVD-Audio/Dolby Digital 2 /DTS/MP3, and a system controller which controls
the system.
The front end section realizes optical head signal computation processing and RF signal processing, digital signal
processing (16-8 demodulation, error correction) for DVD-ROM playback according to the DVD specifications,
digital signal processing of CD-DA/CD-ROM (error correction), AV decoder transfer, servo control, spindle motor control
and seek control.
In the case of MN2DS0016AAUB, the front end servo system waveforms, such as FE, TE and AS, are not observed
as in the case of DVD mechanism module (MS4) CX-3183. Please pay attention.
B
1.1 Analog block (MN2DS0016AAUB : IC1501)
The functions of the analog block are as described below.
1. Reference power circuit
2. SERVO system/DPD system signal processing circuit
Gain switching amplifier and Low Pass Filter (LPF)
3. RF signal processing circuit
RF adding circuit, circuit to make inline, Variable Gain Amplifier (VGA) circuit
4. Laser power control (LPC) circuit
5. A/D converter for SERVO (10 bit, DPD system-4ch), PWM
C 1.1.1 APC circuit
The optical output of the laser diode (LD) has a large negative temperature characteristic.
Therefore, if the LD is driven by a constant current, a constant optical output cannot be obtained.
APC circuit is a circuit to control the current so that the output at the monitor diode (MD) will be constant.
MN2DS0016AAUB includes 2 types of APC circuit, one for DVD and the other for CD.
The LD current can be obtained by dividing the measured voltage between DVDLD1 (CDLD1) and 5 V by 6
(1.5 x 4=6 ), in the case of DVD (CD). It will be approximately 50 mA (45 mA) in the case of DVD (CD).
The potential difference between DVDLD1(CDLD1) and 5 V is set to approx. 300 mV(270 mV).
D
CDMPD 14
DVN Chip
E (MN2DS0016AAUB : IC1501)
DVDMPD
PU UNIT
F
CX-3212
2
1 2 3 4
1.1.2 FE forming circuit
Focus error (FE) forming circuit
5
5
The signal from PU, FE1 and FE2, are AD converted inside IC1501 and captured. After that, a differential is obtained by taking the offset cancellation into consideration,
and FE is obtained.
FE = (FE1) - (FE2)
CN1101
Input AMP LPF Buffer Selector Buffer AMP ADC driving AMP ADC
VIN6
LPF
FE2 137 50 k/100 kHz
12
Gain switching
G=0 dB Selector ADC
-6 dB, 0 dB, 9.5 dB
6
6
VIN5 Gain switching Gain switching
11 LPF 3 dB, 9 dB 6/7.5/9/10.5/
FE1 136 50 k/100 kHz 12/13.5/15/
16.5/17/19.5 dB
DVN Chip
After 10 bit ADC
FE signal forming circuit
CX-3212
1+Pfbal0,1/0x0100
FE1
AMP
7
7
+
Offset cancel Fbal coarse adjustment value FE
-
1-Pfbal0,1/0x0100
FE2
DVN Chip
8
8
3
E
A
D
C
F
B
F
E
B
A
D
C
4
1.1.3 TE forming circuit
Tracking error (TE) forming circuit
In the case of a DVD, the phase difference method is used for TE forming, and the TE is formed from the phase difference among (A+C) and (B+D).
1
1
In the case of a CD, 3 beam method is used, and after entering the signal into a variable amplifier for tracking offset adjustment via an external resistor, it is AD converted,
and a TE is formed by the equation of TE=(E+G_E+F)-(F+H_G+H).
DVD (phase difference TE)
CN1101
Input AMP LPF Buffer HPF AMP ADC Phase comparator LPF (integrator) TE signal forming circuit
Gain switching Gain switching