Jvc THV 70 Service Manual 2
This is the 56 pages manual for Jvc THV 70 Service Manual 2.
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Extracted text from Jvc THV 70 Service Manual 2 (Ocr-read)
Page 1
TH-V70 1-2 1. This design of this product contains special hardware and many circuits and components specially for safety purposes. For continued protection, no changes should be made to the original design unless authorized in writing by the manufacturer. Replacement parts must be identical to those used in the original circuits. Services should be performed by qualified personnel only. 2. Alterations of the design or circuitry of the product should not be made. Any design alterations of the product should not be made. Any design alterations or additions will void the manufacturer`s warranty and will further relieve the manufacture of responsibility for personal injury or property damage resulting therefrom. 3. Many electrical and mechanical parts in the products have special safety-related characteristics. These characteristics are often not evident from visual inspection nor can the protection afforded by them necessarily be obtained by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified in the Parts List of Service Manual. Electrical components having such features are identified by shading on the schematics and by ( ) on the Parts List in the Service Manual. The use of a substitute replacement which does not have the same safety characteristics as the recommended replacement parts shown in the Parts List of Service Manual may create shock, fire, or other hazards. 4. The leads in the products are routed and dressed with ties, clamps, tubings, barriers and the like to be separated from live parts, high temperature parts, moving parts and/or sharp edges for the prevention of electric shock and fire hazard. When service is required, the original lead routing and dress should be observed, and it should be confirmed that they have been returned to normal, after re-assembling. 5. Leakage currnet check (Electrical shock hazard testing) After re-assembling the product, always perform an isolation check on the exposed metal parts of the product (antenna terminals, knobs, metal cabinet, screw heads, headphone jack, control shafts, etc.) to be sure the product is safe to operate without danger of electrical shock. Do not use a line isolation transformer during this check. Plug the AC line cord directly into the AC outlet. Using a "Leakage Current Tester", measure the leakage current from each exposed metal parts of the cabinet, particularly any exposed metal part having a return path to the chassis, to a known good earth ground. Any leakage current must not exceed 0.5mA AC (r.m.s.). Alternate check method Plug the AC line cord directly into the AC outlet. Use an AC voltmeter having, 1,000 ohms per volt or more sensitivity in the following manner. Connect a 1,500 10W resistor paralleled by a 0.15 F AC-type capacitor between an exposed metal part and a known good earth ground. Measure the AC voltage across the resistor with the AC voltmeter. Move the resistor connection to each exposed metal part, particularly any exposed metal part having a return path to the chassis, and meausre the AC voltage across the resistor. Now, reverse the plug in the AC outlet and repeat each measurement. Voltage measured any must not exceed 0.75 V AC (r.m.s.). This corresponds to 0.5 mA AC (r.m.s.). 1. This equipment has been designed and manufactured to meet international safety standards. 2. It is the legal responsibility of the repairer to ensure that these safety standards are maintained. 3. Repairs must be made in accordance with the relevant safety standards. 4. It is essential that safety critical components are replaced by approved parts. 5. If mains voltage selector is provided, check setting for local voltage. Good earth groundPlace this probe on each exposed metal part. AC VOLTMETER (Having 1000 ohms/volts, or more sensitivity) 1500 10W 0.15 F AC TYPE ! Burrs formed during molding may be left over on some parts of the chassis. Therefore, pay attention to such burrs in the case of preforming repair of this system. In regard with component parts appearing on the silk-screen printed side (parts side) of the PWB diagrams, the parts that are printed over with black such as the resistor ( ), diode ( ) and ICP ( ) or identified by the " " mark nearby are critical for safety. (This regulation does not correspond to J and C version.)
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TH-V70 1-3 Conductive material (conductive sheet) or iron plate (caption) Anti-static wrist strap Short lands DVD servo board Flexible wire CN202 CN201 DVD mechanism assembly Connector 5. Attention when traverse unit is decomposed *Please refer to "Disassembly method" in the text for the DVD pickup unit. Apply solder to the short lands before the flexible wire is disconnected from the connector on the DVD servo board. (If the flexible wire is disconnected without applying solder, the DVD pickup may be destroyed by static electricity.) In the assembly, be sure to remove solder from the short lands after connecting the flexible wire. Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged, can destroy the laser diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs. Preventing static electricity 1. Grounding to prevent damage by static electricity Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as DVD players. Be careful to use proper grounding in the area where repairs are being performed. 2. About the earth processing for the destruction prevention by static electricity Ground the workbench by laying conductive material (such as a conductive sheet) or an iron plate over it before placing the traverse unit (optical pickup) on it. 2-1 Ground the workbench 2-2 Ground yourself Use an anti-static wrist strap to release any static electricity built up in your body. In order to maintain quality during transport and before installation, both sides of the laser diode on the replacement optical pickup are shorted. After replacement, return the shorted parts to their original condition. (Refer to the text.) Do not use a tester to check the condition of the laser diode in the optical pickup. The tester's internal power source can easily destroy the laser diode. 3. Handling the optical pickup 1. 2. Do not subject the traverse unit (optical pickup) to strong shocks, as it is a sensitive, complex unit. Remove solder of the short lands on the flexible wire after replacing the optical pickup. For specific details, refer to the replacement procedure in the text. Remove the anti-static pin when replacing the traverse unit. Be careful not to take too long a time when attaching it to the connector. Handle the flexible wire carefully as it may break when subjected to strong force. It is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it. 4. Handling the traverse unit (optical pickup) 1. 2. 3. 4.
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TH-V70 1-37 162 163 - 168 169 170 171 172 - 176 177 178 - 180 181 182 183 184 - 187 188 189 190 191 192 193 194,195 197 - 200 202,203 205 - 209 211 196 201 204 210 212 213 214 215 216 217 218 219 - 223 224 225,226 227 228 229 230 231,232 233 234 - 236 237 238 - 240 Vssio AD13 - AD8 Vddio PWE1- Vss AD7 - AD3 Vssio AD2 - AD0 Vddio PWE0- ALE LA0 - LA3 Vssio RD- LHLDA LHLD Vdd PCS0 XIO1,XIO2 XIO3 - XIO6 XIO7,XIO8 XIO9 - XIO13 XIO14 Vddio Vss Vssio Vddio Vdd DSYNC DREQ DCLK DSTB DVD0 Vssio DVD1 - DVD5 Vddio DVD6,DVD7 MD0 Vssio MD1 Vss MD2,MD3 Vddio MD4 - MD6 Vssio MD7 - MD9- I/O - I/O - I/O - I/O - I/O I/O I/O - I/O O I - O I/O - - - - - I O I I I - I - I I/O - I/O - I/O - I/O - I/O Function I/O Pin No. Symbol Ground P multiplexed address/data bus Power supply (3.3V) Byte write enable for FLASH, EEPROM,SRAM or peripherals Ground P multiplexed address/data bus Ground P multiplexed address/data bus Power supply (3.3V) Byte write enable for FLASH, EEPROM,SRAM or peripherals Address latch enable Latched address [3:0] Ground Read Bus hold acknowledge in slave mode Bus hold request from external master in slave mode Power supply (1.8V) Peripheral chip select 0, generally used for enabling the program store ROM/FLASH Programmable general purpose external input/output (XIO) also used as peripheral chip select, interrupt, Pulse Width Modulator (PWM) output and other system signals Power supply (3.3V) Ground Ground Power supply (3.3V) Power supply (1.8V) DVD parallel mode Sector Sync DVD parallel mode Data Request Data sampling clock Parallel mode Data Valid, serial mode left/right clock DVD drive parallel data port Ground DVD drive parallel data port Power supply (3.3V) DVD drive parallel data port SDRAM data bus Ground SDRAM data bus Ground SDRAM data bus Power supply (3.3V) SDRAM data bus Ground SDRAM data bus
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TH-V70 1-42 1 2 3 4 5 6 7 8 9 10 1133 32 31 30 29 28 27 26 25 24 23 12 13 14 15 16 17 18 19 20 21 2244 43 42 41 40 39 38 37 36 35 34 SDOS I2C SMUTE BICK LRCK SDTI1 SDTI2 SDTI3 SDTO D. AU X DFSDZF2 RIN+ RIN- LIN+ LIN- ROUT1 LOUT1 ROUT2 LOUT2 ROUT3 LOUT3 NC DZFE TVDD DVDD DVSS PDN TST NC ADIF CAD1 CAD0LOOP1 CDTI CCLK CSN P/S MCLK DZF1 AVSS AVDD VREFH VCOM 1.Terminal layout LIN+ LIN- RIN+ RIN- LOUT1 ROUT1 LOUT2 ROUT2 LOUT3 ROUT3LPF LPF LPF LPF LPF LPFDAC DAC DAC DAC DAC DACDATT DATT DATT DATT DATT DATT ADC ADCHPF HPFAudio I/F MCLKBICKLRCK SDOUT SDIN1 SDIN2 SDIN3SDTO SDTI1 SDTI2 SDTI3SDOS D. AU X Format Converter Block Diagram (DIR and AC-3) DSP are external parts) 2.Block diagram AK4527BVQP (IC401) : A/D,D/A Converter SDOS I2C SMUTE BICK LRCK SDTI1 SDTI2 SDTI3 SDTO D. AU X DFS NC DZFE TVDD DVDD DVSS PDNSDTO Source select pin "L" : Internal ADC output, "H" : DAUX input ORed with serial control register if P/S="L". MCKO Clock frequency select pin "L" : MCLK, "H" : MCLK/2. ORed with serial control register if P/S= "L". Connect to GND Audio serial data clock pin Input/Output channel clock pin DAC1 Audio serial data input pin DAC2 Audio serial data input pin DAC3 Audio serial data input pin Audio serial data output pin AUX Audio serial data input pin Double speed sampling mode pin "L" : Normal speed, "H" : Double speed, the ADC is powered down. ORed with serial control register if P/S="L". De-emphasis pin (Not connect) ORed with serial control register if P/S="L" De-emphasis Pin ORed with serial control register if P/S="L" Master clock output pin Digital power supply pin Digital ground pin Power-down & Reset pin When "L", the AK4527 is powered-down and the control registers are reset to default state. If the state of CAD0-1 changes, then the AK4527 must be reset by PDN. I I I I I/O I I I O I I - I O - - I 3. Pin function 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Pin No. Symbol I/O Function