PIONEER CX 3017 Service Manual

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 2004

ORDER NO.

CRT3285

DVD MECHANISM MODULE(MG3)

CX-3017

This service manual describes the operation of the DVD mechanism modules incorporated in the models listed below. When performing repairs use this manual together with the speciﬁc manual for the model under repair.

Model No. Service Manual DVD Mechanism Module

FX-MG9637DVZT/RF FX-MG9637DVZT/RC

CRT3280 CXK7202

CONTENTS

1. CIRCUIT DESCRIPTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2. MECHANISM DESCRIPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

3. DISASSEMBLY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

K-ZZU. JULY. 2004 printed in Japan

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1.CIRCUIT DESCRIPTIONS

1.1 Front-end processor (FEP) section (AN8703FH: IC1101)

The AN8703FH generates servo signals for focus and tracking operations, processes the RF signal, and controls the laser power of the pickup. For servo signal processing, the IC contains a focus operational amplifier, a focus balance adjustment circuit, a threebeam tracking operational amplifier, a phase-difference tracking detection circuit, a tracking balance adjustment circuit, and an envelope detection circuit. For the RF signal processing, the AGC and equalizer functions are contained in the IC.

F or CD

170mV

–

F or DVD

180mV

– +

LPC02

LPC2

LPC01

LPC1

+5V

3.9Ω 3.9Ω 3.9Ω 3.9Ω

3.9Ω 3.9Ω 3.9Ω

3.9Ω

CDLD1

CDLD0

DVDLD1

DVDLD0

CN1101

78LD

78MD

65LD

65MD

CD LD

+5V

DVD LD

AN8703FH

PU UNIT

1.1.1 APC circuit

The light output of laser diodes (LD) has largely negative thermal characteristics. If they are driven with a constant current, the laser power level will not be constant. The APC circuit is designed to control the current so that the laser power becomes constant through the monitor diode (MD). The IC AN8703FH contains two APC circuits, one for DVDs and the other for CDs. The LD current values for DVDs can be calculated by dividing the voltage between the DVDLD1

(or CDLD1 for CDs) and 5V line by 15.6 ohms (3.9 ohms x 4): approximately 26mA and 44mA for DVDs and CDs respectively.

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CX-30172

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1.1.2 Focus error (FE) generating circuit

CN1101

57 VIN1

The pin numbers and names in the brackets are for CDs. The circuits for CDs and DVDs are identical, except for the input terminals of the signals B1 through B4.

(49 VIN5)

58 VIN2

(50 VIN6)

59 VIN3

(51 VIN7)

60 VIN4

(52 VIN8)

AN8702 FH

G4 1+f

G4 1–f

–

Control

FBAL7

VHALF

1.65V

21 FEN

FEY FEX FE

–

22 FEOUT

VHALF

117 AD0

MNZS26EDCUB

Focus error (FE) generating circuit

The signals B1 through B4, obtained by dividing the output in the pickup, are applied to the FE generating circuit. Inside the circuit, the (B1 + B3) and (B2 + B4) signals are generated via the internal resistors, fed into the variable amplifier for the focus balance adjustment, and finally the FE signal is generated by amplifying the {(B1 + B3) – (B2 + B4)} signal.

CX-3017

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1.1.3 Tracking error (TE) generating circuit

• CD (three-beam TE)

CN1101

VIN12

TBAL

VIN11

TEOUT

TEY TEX TE

118 ADI

AN8703FH

TBAL

TEN

VHALF

MNZS26EDCUB

• DVD (phase difference TE)

VIN1 15

VIN2 13

VIN3

VIN4

TBAL

AN8703FH

Differential Phase Det.

TBAL

TEOUT

TEN

VHALF

118 ADI

TEY TEX TE

MNZS26EDCUB

Tracking error (TE) generating circuit

For DVDs, the TE signal is generated by utilizing the phase difference between the (B2 + B4) and (B1 + B3) signals (the phase difference method). For CDs, the A and C signals are applied to the TE generating circuit via the external resistors. Inside the circuit the signals are fed to the variable amplifier for the tracking balance adjustment, and finally the TE signaal is obtained by amplifying the (A – C) signal (the three-beam method).

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CX-30174

Near the disk

Away from the disk

Lens

VHALF

Focal point

RFENV

5678

1.2 Optical disc controller (SODC) section (MNZS26EDCUB: IC1301)

The MNZS26EDCUB, an optical disc controller (SODC) for DVD-ROM/DVD players, is one of a signal processing LSI conformingto the DVD standards. This IC works as a servo controller for the focus, tracking and traverse operations, a spindle motor controller, a seek controller, a digital signal processor for DVD-ROM/RAM reproduction (8/6 demodulation and error correction), and a digital signal processor for CD-ROMs (error correction). In the DSC (Disc Servo Controller) employing an arithmetic processor as a core, analog circuits such as A/D and D/A converters and PLL, and digital circuits including a PWM converter and a cycle timer are contained. In the CIRC, a digital signal processor for CD-DA and CD-ROMs (EFM demodulation and error correction), a spindle motor digital servo processor, and a 1-bit D/A converter with a digital filter (with a secondary low-pass filter, differential OP amplifier output) are prepared. This LSI has easily realized a complete CD/DVD-ROM system.

1.2.1 Focus close

FODRV

After a focus close command is issued, the following procedures are performed irrespective of DVDs and CDs:

1. Measuring and optimizing the signal levels The pickup lens initially moves away from the disc, and then toward the disc. When the pickup lens passes the focal

point, the FE, AS and RFENV signal levels are measured to optimize the FE and AS signal levels (1 and 2 shown in the above diagram).

CX-3017

2. Focus closing Next, the pickup lens moves away from the disc to detect the focus closing levels for FE and AS signals. The focus

loop filter operates to close the focus loop (3 through 6 in the above diagram).

3. Verifying focus close completion The focus close completion is verified by observing the AS and RFENV signal levels (6 and 7 in the above diagram).

In the test mode, focus search is used to verify the FE, AS and RFENV signal levels and the focus drive voltage.

1.2.2 Tracking close

After a tracking-close command is issued, the following procedures are performed irrespective of DVDs and CDs:

1. Tracking brake A half cycle of the track-cross (TKC) signal is measured. If the measured cycle falls within the prescribed range, then a brake pulse signal is output. The direction of the brake pulse depends on the relation in phase between the

OFTR signal and TKC signal (which is obtained by converting the TE signal into a binary signal). When it is confirmed that the stability in lens operation against the disc has been obtained, the brake pulse output will be terminated, and the operation will proceed to the track-closing mode. If it is not confirmed, the brake pulse output will be terminated 10msec. after the brake pulse signal is output, then the operation will automatically proceed to the track-closing mode.

2. Tracking closing The tracking drive-hold process is performed with the OFTR signal.

3. Verifying tracking close completion The success or failure in tracking close depends on the number of tracks that the pickup crosses within the prescribed period. That is, when the number is the prescribed one or less, the system senses that the tracking close is completed. The time limit for the tracking close verification process is 20msec. The retry operation will be carried out with the command from the microcomputer if the verification has not been completed within the time limit.

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1.2.3 Track jump

This system performs track jumps by selecting the following three modes depending on the number of tracks to be skipped: Interval jump, multi jump and traverse jump.

1. Interval jump In this mode, a single-track jump is performed repeatedly. This mode is used for fine seek operation when the

pickup has approached the target track or adjacent tracks are targeted.

2. Multi jump

This mode performs the pickup track-count movement by counting both edges of the TKC signal to jump the target number of tracks.

3. Traverse seek

In this mode, the time is measured with the TKC signal to control the pickup speed. During the movement of the pickup, its vibration is minimized.

The track-jump mode settings for DVDs and CDs are shown below:

Target number of tracks Tr DVD 1~10 11~100 Multi jum 101~500 Combination of multi jump and interval jump 501~ Traverse seek

CD 1~10 11~32 33~500 501~

ack jump mode

Interval jum

The waveform in each of the track-jump modes is shown in the following pages.

CX-30176

1234

5678

Tracking–on process

Interval jump (one track)

Toward outer tracks Toward inner tracks

TE Y

CO±

CX-3017

Multi jump (32 tracks)

Toward outer tracks Toward inner tracks

TEY TEY

1234

CO±

Traverse seek (501 tracks)

Toward outer tracks Toward inner tracks

CO±

TEYTEY

CO±

Traverse seek (5,000 tracks)

Toward outer tracks Toward inner tracks

TEY TEY

CO±

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CX-30178

(Layer 1)

(Layer 0)

Objective lens

L0 L1

5678

1.2.4 Focus jump

Focus jump is used for single-sided, double-layered or double-sided, double-layered discs. The layer closest to the objective lens is called layer 0 (L0), and the other layer is layer 1 (L1).

The waveforms in the focus jump mode are shown below:

Focus jump waveform

L0→L1 L1→L0

The focus-jump operation flow is described below:

1. The tracking loop is unlocked on the layer that is being played.

2. A jump command is issued to jump to the targeted layer.

3. The tracking loop closes on the targeted layer and reproduction starts.

The detailed processes after a jump command is issued are as follows:

1. The pickup lens is accelerated towards the target layer until the FE signal detects the focus jump acceleration completion level. If the acceleration timeout occurs before the acceleration completion level is detected, the acceleration is forcibly terminated.

2. No drive voltage is applied until the FE signal detects the deceleration starting level, and the lens is kept moving by the inertia.

3. With the deceleration starting level detected, the lens starts decelerating, and continues it until the deceleration completion level is detected. If the deceleration timeout occurs before the deceleration completion level is detected, the deceleration is forcibly terminated.

CX-3017

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1.3 Automatic adjustment functions

This system automatically performs all circuit adjustments by combined operations of the ICs AN8703FH (FEP) and

MNZS26EDCUB (SODC). Each automatic adjustment function is explained below:

1.3.1 FE, TE and AS offset cancel The analog signals FE, TE and AS, generated by the FEP, are A/D-converted by the A/D converter inside the SODC. When the power is turned on, the offset cancel works to cancel the input offset of the A/D converter.

1.3.2 Data slice balance (DBAL) adjustment The DBAL adjustment is made to adjust the data-slice level that is used when the RF signal from the FEP is converted to a binary signal in the SODC. When the power is turned on, the test signal of the constant frequency is output from the SODC and the jitter component of the signal is adjusted to the minimum.

1.3.3 In the same manner as the above, the PLL balance (PBAL) adjustment is made to optimize the current level balance

between the P-ch and N-ch sides of the chargeable pump.

1.3.4 FE regulating adjustmen

t The FE signal level measured when the focus loop is closed is A/D-converted in the SODC. Then it is adjusted so that it becomes 190LSB at the input stage of the digital equalizer.

1.3.5 Spindle gain learning The time is measured that is required for the spindle motor to start rotating in the stop mode and reach the prescribed rotation. The measured time is used to adjust the SPDL gain, thereby absorbing the variation in the motor torque.

1.3.6 Tracking balance (TBAL) adjustment

In the focus close and tracking open mode, the lens is vibrated in the tracking direction. The tracking balance is adjusted so that the DC offset becomes zero (the balance point) by using the Newton-Raphson’s method.

1.3.7 Tracking error amplitude learning In the focus close and tracking open mode, the lens is vibrated in the tracking direction. After A/D-converted in the ADSC, the amplitude level of the TE signal is adjusted so that it becomes 190LSB at the input stage of the digital equalizer.

1.3.8 Focus balance (FBAL) adjustment In the tracking close mode, the focusing position is adjusted by minimizing the RFENV.

1.3.9 Focus gain and tracking gain adjustments

In the tracking close mode, some disturbance signal is applied to the servo loops. The focus and tracking gains are adjusted to the target gain cross points.

1.3.10 AS regulating adjustment In the tracking close mode, the AS signal level is sampled the prescribed times. After A/D-converted in the ADSC, this signal is adjusted so that it becomes 64LSB at the input stage of the digital equalizer.

CX-301710

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+ 21 hidden pages