LG CRD-8522B Service Manual

INTRODUCTION

GENERAL FEATURE

SPECIFICATIONS

1. MODEL: CRD-8484B

1) SUPPORTED SYSTEM

• IBM Compatible 486SX or Above (With PIO mode 4 recommended)

2) SUPPORTED OS

3) GENERAL PERFORMANCE

• Data Transfer Rate .........................................................................................Sustained Data Transfer Rate

22Times Speed (Inner side) : 3,300 kbytes/sec

48 Times Speed (max., Outer side) : 7,200 kbytes/sec

• Data Buffer Capacity.....................................................................................................................128 kbytes

• Access Time.......................................................................................Random Access Time : 75 ms Typical

4) POWER REQUIREMENTS

• Voltage ......................................................................................................................................+5V DC +5%

+12V DC +5%

• Ripple ..................................................................................................................+5V : Less than 100mVp-p

+12V : Less than 100mVp-p

• Current .......................................................................................................................+5V : 0.9A (Maximum)

+12V : 1.5A (Maximum)

5) AUDIO PERFORMANCE

• Frequency Response.....................................................................................................20Hz~20KHz(+3dB)

• S/N Ratio (IHF-A+20 KHz LPF) .......................................................................75 dB (Typical at 1 KHz 0dB)

70 dB (Limit at 1 KHz 0dB)

• T.H.D. (IHF-A+20 KHz LPF)............................................................................0.05% (Typical at 1 KHz 0dB)

0.15% (Limit at 1 KHz 0dB)

• Channel Separation (IHF-A+20 KHz LPF).............................................................................75 dB (Typical)

70 dB (Limit)

• Output Voltage (1kHz 0dB) 47KΩ Load...............................................................................0.75Vrms + 10%

• Headphone Level (1kHz 0dB) 33Ω Load...............................................................................0.7Vrms + 20%

• Enhanced IDE interface

• Internal 5.25 inch, halfheight CD-ROM Drive

• Fast 75ms Average Access Time

• Max 7,200KB/sec Sustained Transfer rate

• Photo-CD Multisession Disc Spec compliant

• Multimedia MPC-3 Spec compliant

• Power Tray Loading/Ejection Mechanism

• 3 Way Eject support (Software, O/C Button, Emergency Eject)

• Closed Enclosure

• Built-in ATAPI Interface Controller

• Software Volume Control

• 8 Times Digital Filter for CD Audio

• Built-in MODE-1 ECC/EDC

• MTBF 125,000h POH (at 10% Utilization)

• PIO Mode 4 & Multi DMA Mode 2 support

• Horizontal or Vertical Mounting

• Digital audio output connector

• Digital audio through ATAPI Interface

• Subcode (P-W) through ATAPI Interface

• Spin-down Mode for energy saving

• MS-DOS Version 3.1 or Higher

• Windows '95/'98/’2000

• Solaris Ver 2.4 or Higher

• Linux slackware Ver 2.3

• Windows NT 4.0 or later

• OS/2 Warp (Ver 3.0)

This service manual provides a variety of service information. It contains the mechanical structure of the CD-ROM Drive together with mechanical adjustments and the electronic circuits in schematic

form. This CD-ROM Drive was manufactured and assembled under our strict quality control standards and meets or exceeds industry specifications and standards.

2. Trouble List (Circuit)

A. LED doesn’t light. B. Pick-Up doesn’t move to the inner-track. C. The Laser of Pick-Up doesn’t light. D. Pick-Up lens doesn’t move up and down. E. Disc doesn’t rotate. F. TOC isn’t read. (The LED turns on, but doesn’t flicker.) G. During Audio CD Play, LED flickers, but Speaker is silent.

TROUBLESHOOTING GUIDE

1. Initial Lead-in Operation

Reset or Power-On.

LED Flickers.

Pick-Up moves to the inner-Track.

Laser on the Pick-Up lights.

Focus Search (through moving up and down the lens of Pick-Up)

Focus Servo On (FEO(TP15) signal generation)

Rotate disc.

Tracking Servo On (TEO(TP14) Signal generation)

Spindle Servo On (SPO(TP25) Signal generation)

Read TOC Area (LED Flickers)

Search the Start of Data Area and then pause.

3. Troubleshooting Guide

A. LED doesn’t light.

Check Power Voltage (TP1:3.3V, TP2:12V) Reference Voltage

[TP3:VC(2.5V) and GND.]

Does “H” output in IC501 pin ?

Check and replace R105, R106, Q12 and LED701 (LED702 for NECCI).

Is the CLOCK Frequency of IC501 pin ,

33.86MHz?

Check the power input pattern.

Check IC501.

Check and replace X10;

33.86MHz.

Is the CLOCK Frequency of IC501 pin

33.86MHz?

Check and replace IC501.

YES

170

A-1

B. Pick-Up doesn’t move to the inner track.

Do the signals appear at IC501 pin , ? (Refer to Fig. B-1.)

Do the signals appear in PN301 pin? (Refer to Fig. B-2.)

Does “H” output at IC201 pin ?

Is the 2.5V at IC201 pin ?

Check the pattern from IC501 pin to IC201 pin

Check IC501.

Replace IC102.

Check the PN301, and then replace the Sled Motor.

YES

Replace IC201.

107

CH1 PIN34 DA0

CH2 PIN35 DA1

CH1 TP4

(/A)

(A)

(/B)

(B)

CH2 TP5

CH3 TP6

CH4 TP7

Fig. B-1. DA0 and DA1 Signals

Fig. B-2. TP4, TP5, TP6 and TP7 Signals

Check the pattern from IC501 pin to R42 and then replace IC501.

Does “Low” output at IC102 pin ?

Is the voltage of IC102 pin

(LDD) 2V?

Check Pick-Up FFC, PN101.

Check Q10, C10, C32, R113, R114 and then replace IC102.

Replace IC501.

YES

157

Does the focus search signal appear at FDO (TP9)? (Refer to Fig. D-1.)

Is the 2.5V at IC201 pin ?

Replace IC102.

YES

Replace IC201.

Does the focus search signal appear between F+ (TP10) and F- (TP11)? (Refer to Fig. D-2.)

C. The Laser of Pick-Up doesn’t light.

D. The Pick-UP lens doesn’t move up and down.

D-1

Check the pattern from pin , of IC201 to pin , of PN101.

Check the PN101, Pick-Up FFC.

Replace the Pick-Up.

Replace PN101 or Pick-Up FFC.

CH1 TP9 (FDO)

CH1 TP10(F+) TP11(F-)

Fig. D-1. FDO Signal

Fig. D-2. Focus Search Signal

D-1

Does the signal appear at the SP0 (TP25)? (Refer to Fig. E-3.)

Do the signals appear at IC201 pin (W), (V), and (U)?

Replace IC501.

Replace IC201.

YES

Check the pattern from IC201 pin , , to PN201 , , .

YES

Check Spindle Motor FFC

and then replace the

Spindle Motor.

Does the signal appear at FEO (TP15) when the IC501 pin opened? (Refer to Fig. E-1.)

YES

Replace IC501.

Replace Pick-Up.

Do the signal appear at TP15 (FEO)? (Refer to Fig. E-2.)

Does the signal appear at F+(TP10) during focus search?

E. Disc doesn’t rotate.

144

Fig. E-2. FEO Signal

CH1 TP15: FEO

Fig. E-3. SPO Signal

CH1 TP25: SPO

Fig. E-1. S-Curve

CH1 TP15: S-Curve

+ 16 hidden pages