Bose-500PM-spk-sm维修电路原理图.pdf

Model 500PM LoudspeakerService Manual1998 Bose CorporationPart Number 197275 REV 00RadioFans.CN 收音机爱 好者资料库2CONTENTSElectrostatic Discharge Sensitive (ESDS) Device Handling . 3Warranty Information. 3Specifications. 4Theory of Operation, Model 500PM Loudspeaker SmartProtect Crossover PCB. 5Disassembly/Assembly Procedures . 6-8Figure 1. Model 500PM Loudspeaker Driver Wiring Diagram. 7Test Procedures . 9Figure 2. Model 500PM Loudspeaker Test Setup Diagram . 9Main Part List, Model 500PM Loudspeaker (see Figure 3) . 10Figure 3. Model 500PM Loudspeaker Exploded View . 11Electrical Part List. 12-13Packing List, Model 500PM Loudspeaker (see Figure 4) . 14Figure 4. Model 500PM Loudspeaker Packing View . 14Figure 5. Model 500PM Loudspeaker Crossover PCB Topside Component andEtch Layout Diagram. 15Figure 6. Model 500PM Loudspeaker Crossover PCB Bottom Side Etch Layout Diagram . 16Figure 7. Model 500PM Loudspeaker SmartProtect Crossover Assembly Schematic Diagram. 17PROPRIETARY INFORMATIONTHIS DOCUMENT CONTAINS PROPRIETARY INFORMATION OFBOSE CORPORATION WHICH IS BEING FURNISHED ONLY FOR THE PURPOSE OF SERVICING THE IDENTIFIED BOSE PRODUCT BY AN AUTHORIZED BOSE SERVICE CENTER OR OWNER OF THE BOSE PRODUCT, AND SHALL NOT BE REPRODUCED OR USED FOR ANY OTHER PURPOSE.CAUTION: The Model 500PM Loudspeakercontains no user serviceable parts. To preventwarranty infractions, refer servicing to warrantyservice centers or factory service.RadioFans.CN 收音机爱 好者资料库Note: This manual has been updated using information from supplement197275-S1. This affects part numbers for PTC1, PTC2 and PTC3.3(ESDS) DEVICE HANDLINGELECTROSTATIC DISCHARGE SENSITIVEThis unit contains ESDS devices. We recommend the following precautions when repairing,replacing, or transporting ESDS devices:Perform work at an electrically grounded work station.Wear wrist straps that connect to the station or heel straps that connect to conductive floor mats.Avoid touching the leads or contacts of ESDS devices or PC boards even if properly grounded.Handle boards by the edges only.Transport or store ESDS devices in ESD protective bags, bins, or totes. Do not insertunprotected devices into materials such as plastic, polystyrene foam, clear plastic bags, bubblewrap, or plastic trays.WARRANTY INFORMATIONThe Model 500PM Loudspeaker is covered by a 5-year transferable limited warranty.4SPECIFICATIONSExternal Dimensions, Single Speaker,including grille:18.09L x 11.77D x 10.10H(45.95 x 29.90 x 25.65 cm)Weight:Packed Pair, 60lb (27.3kg)Shading Network Assembly:5.6uF capacitor with 0.13mH series inductor,33uF capacitor with 0.5mH series inductor, 33ufcapacitor with 3.9 parallel resistor and 0.8mHparallel inductor.Internal Cabinet Volume:19 Liters netPort (each side):Flared slot port tuned to 58HzImpedance:6 nominal, 4.8 minimum from 20Hz to 20kHzPower Handling:200W (34.6Vrms) continuous per IEC-268-5.Sensitivity:85dB SPL 1W/1m, free-field, per IEC-268-5for octave band centered at 400Hz.SmartProtect:Turn on voltage of the transistorsof the electronic switch:1.5-1.8VrmsResistance prior to turn on:3On resistance:0.2Max audio voltage applied to speaker:70VrmsMaximum cont. sinusoidal current, 1Khz:3.6Arms 15%Maximum cont. sinusoidal current, 150Hz: 5Arms 15%Reset time:200-400msTime to trip, as a function ofspeaker current:DC turn-off current:5ASpeaker CurrentI/ITime to Trip3.31-5ms30.8ms22s1.53s15THEORY OF OPERATIONModel 500PM Loudspeaker SmartProtect Crossover PCBNote: Refer to Figure 7. Model 500PM Loudspeaker SmartProtect Crossover AssemblySchematic Diagram, for the following explanation.The SmartProtect PCB is an electronic switch, in series with the speaker, used to protectthe drivers from high current and power levels. It has a fast turn-on time of about 100milliseconds. At turn-on, current flows through R1, C1, D1, D2, C2, Q1, C3 and R18.Capacitors C2 and C3 form a virtual power supply which is used to power theSmartProtect circuit to provide the bias to FETs Q8 and Q9, limited by the Zener diodeD6 to 10 V. Diodes D1 and D2 form a voltage doubler. Once C2 is charged, Q1 willconduct and provide a charge path for C3. Once C3 is charged, if the input audio voltagebecomes lower than 4V, Q1 will turn off, and the charge on C3 provides a voltage used tooperate the circuit for up to 5 hours. PTC1 provides the current path if the speaker mustplay for a long time at very low volume when input AC voltage to the speaker is less then1.5V.Resistors R16 and R17 form the current sensor. It allows the circuit to sense the speakercurrent and protect it from the following types of the abuse:1. DC offset - when too high a DC offset level is detected one, of the two transistors Q6or Q7 will be turned on through resistor R19, thus tripping the monostable multivibratorQ2, Q3.2. Fast DC/AC transients - works the same way for both transient polarities, thresholddepends on the ratio of resistors R19 and R20.3. Thermal overload - When the AC current is too high for a prolonged time, transistor Q4turns on through resistor R13, tripping the monostable multivibrator Q2, Q3. The timeconstant of current integration depends on C6, R13 while the time constant of “memory” isdefined by R6 and C6. AC voltage divider R15, R14, and C7 defines the frequencydependent threshold of current protection.The protection portion of the circuit works as follows: When monostable multivibrator Q2,Q3 is tripped, by one of the above conditions, transistors Q2 and Q3 turn on, reducingthe gate voltage of Q8 and Q9 to zero, and shutting them off. At this moment the speakerload is disconnected from the amplifier. During the off cycle, capacitor C4 is chargingthrough resistor R3, and when the charging is completed, Q2 and Q3 will shut off again,turning Q8 and Q9 back on, and allowing the speaker to operate again. If the overloadcondition persists, the monostable multivibrator will trip the circuit again, and shut off thespeaker again. Duty cycle depends on the current through the speaker.Troubleshooting1. If PTC1 is open, the unit will not play at low volume levels (Vin1.5 V) when thesystem is first turned on, but as the volume is increased, the SmartProtect circuit will turnon, and the speaker will operate. It will then operate for approximately 5 hours, until thecharge on C3 is too low to keep the circuit running, and then the speaker will shut offagain.2. If either R18, R1, D2 is open, or D1 is shorted there will be no charge of the virtualpower supply formed by C2 and C3, and the circuit will never turn on. The symptom willbe that the speaker will play at low volume levels, but as the volume is turned up, thespeaker will stop operating. This may also happen if for any reason Q7, Q8 or any othercomponent in the circuit fails, and internal safety “watchdog” C5 turns the Q3 onpreventing the Q8 and Q9 from being overheated.Shading NetworkThe shading network consists of one 5.6uF capacitor, one RXE040 PTC, and one 0.13mHinductor across the two front array drivers, one 33uF capacitor, one RXE040 PTC and one0.5mH inductor across the driver nearest the port and a trap filter consisting of a 3.9resistor, a 33uF capacitor, and a 0.8mH inductor. The inductors are iron core.6DISASSEMBLY/ASSEMBLY PROCEDURESNote: Refer to Figure 3. Model 500PMLoudspeaker Exploded View, for thefollowing procedures.1. Grille Removal1.1 Using your fingers, grasp the grille (14)edge nearest the curved end and gentlypull the grille away from the cabinet until itcomes free.1.2 Grasp the opposite edge of the grilleand gently pull it away from the cabinetuntil it comes free as well.2. Grille Replacement2.1 Align the two grille posts on the curvedgrille (14) edge with the cabinet grillesocket grommets (5) located on thespeaker cabinet curved section and pressthe grille edge into place.2.2 Align the two grille posts at theopposite grille edge with the cabinet grillesocket grommets and press the grille inplace. The grille should be neat and flushwith the cabinet.3. StarDriver Removal3.1 Remove the grille (14) usingprocedure 1.3.2 Remove the three screws (2 or 18) thatsecure the StarDriver (6) you wish toremove from the cabinet.Note: The StarDriver located on the angledportion of the baffle is secured using (2),the two StarDrivers located on the plasticbaffle are secured using (18).3.3 Using your fingers, grasp the plasticbasket of the StarDriver and pull gently.The StarDriver should come free.3.4 Note the driver wiring color code, andcut the wires from the harness assembly(3) as close to the terminals as possible.4. StarDriver replacement4.1 Observing polarity, solder the wiresfrom the harness assembly (3) to theStarDriver (6) terminals.4.2 Align the StarDriver correctly into thecabinet and secure it using the screws(2 or 18) removed in procedure 3.2.Do not overtighten the screws.4.3 Replace the grille (14) usingprocedure 2.5. Woofer RemovalNote: In order to gain access to thewoofers, you must first remove the arraybezel on which the forward-firingStarDrivers are mounted.5.1 Using a phillips-head screwdriver,remove the twelve screws (2) that securethe array bezel (12) to the loudspeakercabinet.5.2 Gently pull the array bezel away fromthe loudspeaker cabinet. Be careful not tobreak any wires. Slide the array bezel offto one side to allow access to the wooferassembly (11).5.3 Remove the batting material locatedbehind the array bezel. Retain it forreplacement later.Note: In order to remove the wooferassembly located behind the rod, youmust first remove the StarDriver locatedon the angled portion of the loudspeakercabinet using procedure 3. It is notnecessary to cut the StarDriver wires, asit can be moved out of the way to allowremoval of the woofer.5.4 Using a phillips-head screwdriver,remove the four screws (2) securing thewoofer assembly to the loudspeakercabinet.7DISASSEMBLY/ASSEMBLY PROCEDURESFigure 1. Model 500PM Loudspeaker Driver Wiring Diagram-+BLUEREDGREYWHITEGREENYELLOWBROWNORANGEPCB+-+-_+WHITEGREYREDBLUEBLUEREDYELLOWGREENBROWNORANGE-+-+-BLACKBLACKWOOFERWOOFERDRIVERDRIVERDRIVERNote: When removing the wooferassembly, it is not necessary to cut theblack wire used to connect the dual voicecoils in series. Refer to Figure 1.5.5 Make a note of the wiring color code,and cut the blue and red wires of theharness assembly (3) as close to theterminals as possible.5.6 Once you have the woofer assemblyout of the loudspeaker cabinet, remove theblack wire used to connect the dual voicecoils in the woofer assembly in series.Retain it for use on the replacement wooferassembly.6. Woofer Replacement6.1 Using the wiring diagram, solder theblue and red wires to the correct terminalson the woofer assembly (11) to bereplaced.Note: Be sure to replace the black wireused to connect the dual voice coils on thewoofer assembly in series.6.2 Align the woofer assembly (11) into thespeaker cabinet, making sure that thewoofer gasket (10) is located properlybehind the driver.6.3 Secure the woofer assembly to thespeaker cabinet using the four screws (2)removed in procedure 5.4.6.4 Replace the batting material removedin procedure 5.3.6.5 Align the array bezel (12) so that thetabs located on the sides of the array bezelare located toward the center of thespeaker cabinet.6.6 Secure the array bezel to the speakerusing the twelve screws (2) removed inprocedure 5.1.8DISASSEMBLY/ASSEMBLY PROCEDURES8.2 Using the four screws (9) removed inprocedure 7.5, secure the crossoverassembly to the binding post connector.8.3 Plug the speaker harness (3)connector onto the crossover assembly.8.4 Gently slide the crossover assemblyinto the the speaker cabinet, taking carenot to damage any components. Be surethat the black rubber bumper is installedinto the center of the crossover assembly,and that it remains in place during thisprocedure.8.5 Secure the binding post connector tothe speaker cabinet using the four screws(2) removed in procedure 7.1. Do notovertighten the screws.6.7 Replace the grille (14) usingprocedure 2.7. Crossover Assembly and Binding PostConnector Removal7.1 On the rear of the speaker cabinet,use a phillips-head screwdriver to removethe four screws (2) that secure the bindingpost connector (7) to the cabinet.7.2 Gently pull the binding post connectorstraight out of the speaker cabinet until yousee the crossover assembly (8).7.3 Angle the binding post connector sothat the crossover assembly can be pulledout through the opening on the rear of thespeaker cabinet. Gently pull the crossoverassembly out of the speaker cabinet. Becareful not to damage any components onthe crossover assembly.Note: Be sure to retain the rubber bumperthat is mounted in the center of the PCB.You will need to reinstall it with thecrossover assembly. It is used to preventvibration of the crossover assembly duringloudspeaker operation.7.4 Unplug the speaker harness (3)connector from the crossover assembly.7.5 Use a phillips-head screwdriver toremove the four screws (9) that secure thebinding post connector to the crossoverassembly.7.6 Slide the crossover assembly straightoff of the tabs on the binding postconnector.8. Crossover Assembly and Binding PostConnector Replacement8.1 Slide the crossover assembly (8) ontothe tabs located on the binding postconnector (7).9Figure 2. Model 500PM Loudspeaker TestSetup DiagramNote: Refer to Figure 1. Model 500PMDriver Wiring Diagram, for the followingprocedure.1. Phase Test1.1 Remove the speaker grille usingDisassembly/Assembly procedure 1.1.2 Observing polarity, apply an +8Vdclevel to the input terminals on the rear ofthe loudspeaker. The drivers should moveoutward.1.3 Replace the grille using procedure 2.Note: Refer to Figure 2. Model 500PMLoudspeaker Test Setup Diagram, for thefollowing tests.2. Rub and Tick Test2.1 Remove the grille using procedure 1.2.2 Apply a 6Vrms, 60Hz signal to the inputterminals on the rear of the speakercabinet.2.3 Listen carefully for any buzzes, rattles,or other extraneous noises from the driversor trim parts.TEST PROCEDURESNote: There is a normal suspension noise.To distinguish between a rub or a tick andsuspension noise, displace the driver coneslightly with a finger. If the noise stays thesame, it is suspension noise.2.4 Replace the grille using procedure 2.3. Air Leak Test3.1 Remove the grille using procedure 1.3.2 Apply a 6Vrms, 60Hz signal to theinput terminals on the rear of the speakercabinet.3.3 Test duration should be 15 secondsminimum.3.4 Listen carefully for air leaks along allglue joints, at the binding post connector,and at transducer mounting locations. Airleaks will be heard as a hissing or sputter-ing sound. All repairs must be hidden.3.5 Replace the grille using procedure 2.4. Power Sweep Test4.1 Apply a 6Vrms, 10Hz signal to the inputterminals on the rear of the speakercabinet. Leave the speaker port open.4.2 Sweep the input frequency from 10Hzto 5kHz, and then back down to 10Hz.Note: The whooshing noise from the portat approximately 60Hz is acceptable.4.3 Replace any transducer that has abuzzing noise. There shall not be anybuzzes or rattles from the int