Model : SC - 148B CD-ROM service manual CONTENTS • Specifications • Cautions at Service • External Part Name • Disassembly Method • Exploded Views & Part List • Packing Options • Operational Position Diagram • Block Diagram • Troubleshooting •...
Specifications 1. General Specifications - Drive type : Computer built-in - Frequency response : 20Hz~20KHz (Limeout) - Power consumption : DC + 5V, 1.7A 100Hz~20KHz (H/pout) DC + 12V, 1.0A - Signal to noise ratio : 75dB(1KHz, Limeout) - Dimensions : 149mm(W)X42.5mm(H)X200mm(L) 65dB(1KHz, H/pout) - Net Weight : 950g - Distortion factor : 0.15% Less than(1KHz)
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Main Components Block Diagram and Pin Descrition TA2143FN(I.C-RF)
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PIN DESCRIPTIONS PIN NO PIN NAME FUNCTION POWER SOURCE/VOLTAGE TERMINAL RFGC RF FREQUENCY CONTROL SIGNAL INPUT TERMINAL RPBW SEL TERMINAL COMBINATIAU DETELTOR CONTROL TERMINAL RPBW FC [kHz] L / HiZ L / HiZ L / HiZ L / HiZ L / HiZ L / HiZ MAIN BEAM AMP INPUT TERMINAL MAIN BEAM AMP INPUT TERMINAL...
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PIN DESCRIPTIONS SYMBOL DESCRIPTIONS SYMBOL DESCRIPTIONS VSS3 DIGITAL GND TERMINAL VDD3 DIGITAL +3.3V POWER SOURCE TERMINAL BIT CLOCK OUTPUT TERMINAL (1.4112MHz) APC CIRCUIT ON/OFF SIGNAL OUTPUT TERMINAL AOUT AUDIO DATA OUTPUT TERMINAL FLGA INTERNAL SIGNAL MONITOR OUTER FLAG OUTPUT TERMINAL DOUT DIGITAL OUT OUTPUT TERMINAL FLGB...
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PIN DESCRIPTIONS NO ORIGIN NAME FUNCTION ORIGIN NAME FUNCTION EXT PROM CHIP ENABLE P1.4 PRODUCT TEST PINO /UCS INTERFACE CHIP SELECT P1.3 PRODUCT TEST PIN1 /RD7 /URD INTERFACE CHIP READ P1.2 PRODUCT TEST PIN2 /UWR INTERFACE CHIP WRITE P1.2 TRO_SW TRO CONTROL SWITCH VOLTAGE LEVEL DETECT P1.0...
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PIN DESCRIPTIONS SYMBOL DESCRIPTIONS SYMBOL DESCRIPTIONS MICOM ADDRESS INPUT POWER SOURCE TERMINAL MICOM ADDRESS INPUT POWER SOURCE TERMINAL MICOM ADDRESS INPUT GROUND TERMINAL MICOM READ SIGNAL INPUT TEST0 TEST TERMINAL MICOM WRITE SIGNAL INPUT TEST1 TEST TERMINAL CHIP ENABLE SIGNAL INPUT TEST TERMINAL MINT INTERRUPT REQUEST OUTPUT...
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7S32(I.C-OR GATE) 4S66F(I.C-SWITCH) PQ20WZ51(I.C-REGULATOR) Pin No Pin Name DC input(VIN) ON/OFF control terminal(VC) DC output(VO) Output voltage minute adjustment terminal(VADJ) DAP202K(DIODE ARRAY)
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29EE512-70(I.C-FLASH MEMORY) - PIN DESCRIPTION Symbol Pin Name Functions A15-A7 Row Address Inputs To provide memory addresses. Row addresses define a page for a write cycle. A6-A0 Column Address Inputs Column Addresses are toggled to load page data. DQ7-DQ0 Data Input/output To output data during read cycles and receive input data during write cycles.
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M56788FP(I.C-DRIVE) - PIN DESCRIPTION Terminal Symbol Terminal function Terminal Symbol Terminal function CH3IN CH3 non-inverted input VREF0 Reference voltage output OUT3 E3 amplifier output VREF Reference voltage input IN3- E3 amplifier inverted input SS.GND Small signal GND VBS2 Bootstrap power supply MUTE2 CH5 mute Motor power supply...
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PIN ASSIGNMENT TERMINAL TERMINAL FUNCTION REMARKS SYMBOL L b (G) b-phase upper side power transistor Keep open. (base)output terminal L a (G) a-phase upper side power transistor Keep open. (base)output terminal a-phase output terminal Connect to the coil. V M2 Supply voltage terminal for motor drive Connect to V externally.
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Troubleshooting Equipments required at repair 1. Oscilloscope(100MHz or more ) 2. PROBE for Oscilloscope(10:1) 3. PC(486 ormore) Verify the circuit of power unit and the first status(Plug-in the power cable without I/F cable and verify.) +5V, +12V of CN701 is normally inputted Check power short and power supply cable after connection of power cable? connection state...
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Check after SET assembly Input Voltage of IC201 9pin, 21pin 3.6V ? Pick up moves in at power on after moving out ? 1TRACK JUMP TE Tray in / out ? Refer to Tray open / close Laser diode on ? Refer to No laser diode on Laser diode on ? Refer to No focus lock...
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FPC : Flexible Printed Circuit No tray open/close Start FPC is normally inserted in CN702? Retest after inserting FPC in CN702 properly IC301 44pin is 0V at pressing SW702? Check SW702 pattern and soldering Replace SW702 After FPC short check, no error, check SW soldering of deck CN702 4pin FPC of CN702 is normally inserted? IC301 29pin is 0V with tray in?
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No laser on Open and close tray(Disc insettion) Refer to ‘No tray open/close’ IC101 10pin changes from 0V to +3.3V? Refer to ‘Check power source and initial state’ IC101 9pin changes from 4.2V to 3.6V? Check IC101 power input and replace. CN501 3pin changes from 2V to 2.5V? Check D101, L101, Q102, R102, C103 soldering CN501 2pin changes from 0V to 0.7V?
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No SLED operation Move pick-up out. Insert 2 FPC and power cord. Pick-up moves in? SLED runs normally. The below waveform is outputted in Refer to 'Check power source and initial state' IC301 22Pin, 23pin ? Voltage of IC501 4pin - 12V, Check R506, R507, The below signal is inputted 5pin - 5V?
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No spindle motor rotation Insert disc. Focus lock? Refer to 'No focus lock' The below waveform is Refer to 'No focus lock' inputted in IC502 22Pin? Spindle motor kick signal IC502 4Pin, 29pin is 12V? Check IC301 38pin soldering IC502 5Pin is 5V? Check R323 soldering Check C519 soldering The below waveform is inputted in IC502...
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No audio output Insert audio disc. Focus lock? Refer to 'No focus lock' Spindle Motor rotates? Refer to 'No Spindle Motor rotation' Audio signal is outputted in Replace IC201 Check IC201 power and soldering. IC201 77, 80Pin? Audio signal is outputted in Check IC701 power input and Replace IC701 IC701 1.
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When installing is impossible Connect power cable and I/F cable between PC and CD-ROM Does INSTALL message appear? Normal Is IC301 55PIN 5V when main power turns on? Check main power-end and initial state Is IC201 95PIN 5V? Does X401 oscillate? Check soldering of C401, C402 Do the digital signal of IC301 and IC401 Check the soldering of IC401, IC301...
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Troubleshooting Equipments required at repair 1. Oscilloscope(100MHz or more ) 2. PROBE for Oscilloscope(10:1) 3. PC(486 ormore) Verify the circuit of power unit and the first status(Plug-in the power cable without I/F cable and verify.) +5V, +12V of CN701 is normally inputted Check power short and power supply cable after connection of power cable? connection state...
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Check after SET assembly Input Voltage of IC201 9pin, 21pin 3.6V ? Pick up moves in at power on after moving out ? 1TRACK JUMP TE Tray in / out ? Refer to Tray open / close Laser diode on ? Refer to No laser diode on Laser diode on ? Refer to No focus lock...
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FPC : Flexible Printed Circuit No tray open/close Start FPC is normally inserted in CN702? Retest after inserting FPC in CN702 properly IC301 44pin is 0V at pressing SW702? Check SW702 pattern and soldering Replace SW702 After FPC short check, no error, check SW soldering of deck CN702 4pin FPC of CN702 is normally inserted? IC301 29pin is 0V with tray in?
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No laser on Open and close tray(Disc insettion) Refer to ‘No tray open/close’ IC101 10pin changes from 0V to +3.3V? Refer to ‘Check power source and initial state’ IC101 9pin changes from 4.2V to 3.6V? Check IC101 power input and replace. CN501 3pin changes from 2V to 2.5V? Check D101, L101, Q102, R102, C103 soldering CN501 2pin changes from 0V to 0.7V?
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No SLED operation Move pick-up out. Insert 2 FPC and power cord. Pick-up moves in? SLED runs normally. The below waveform is outputted in Refer to 'Check power source and initial state' IC301 22Pin, 23pin ? Voltage of IC501 4pin - 12V, Check R506, R507, The below signal is inputted 5pin - 5V?
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No spindle motor rotation Insert disc. Focus lock? Refer to 'No focus lock' The below waveform is Refer to 'No focus lock' inputted in IC502 22Pin? Spindle motor kick signal IC502 4Pin, 29pin is 12V? Check IC301 38pin soldering IC502 5Pin is 5V? Check R323 soldering Check C519 soldering The below waveform is inputted in IC502...
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No audio output Insert audio disc. Focus lock? Refer to 'No focus lock' Spindle Motor rotates? Refer to 'No Spindle Motor rotation' Audio signal is outputted in Replace IC201 Check IC201 power and soldering. IC201 77, 80Pin? Audio signal is outputted in Check IC701 power input and Replace IC701 IC701 1.
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When installing is impossible Connect power cable and I/F cable between PC and CD-ROM Does INSTALL message appear? Normal Is IC301 55PIN 5V when main power turns on? Check main power-end and initial state Is IC201 95PIN 5V? Does X401 oscillate? Check soldering of C401, C402 Do the digital signal of IC301 and IC401 Check the soldering of IC401, IC301...
Disassembly Method 1. COVER BOTTOM ASSY disassembly Remove 4 screws on the bottom of COVER BOTTOM ASSY, lift the back up and disassemble COVER BOTTOM ASSY as shown in the figure of the next page. 2. COVER-TOP disassembly After disassembling 6 hooks of FRONT ASSY from COVER TOP , pull COVER TOP forward...