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PFC Circuit

Pin 16 of IC501 also goes low when pin 23 is “high”. When pin 16 goes “low”, the diode within the photo-coupler 
IC401 emits light to turn on the photo-transistor.
Pin 4 of IC401 goes “low”. This “low” is applied to the gate of Q401 turning it on to apply 12V to pin 8 of PFC 
circuit.

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Summary of Contents for TH-37PX60U

Page 1: ...Panasonic Service and Technology Company National Training 10th Generation Plasma Display Television Technical Guide ...

Page 2: ...n warnings or cautions to advise non technical individuals of potential dangers in attempting to service a product Products powered by electricity should be serviced or repaired only by experienced professional technicians Any attempt to service or repair the product or products dealt with in this service information by anyone else could result in serious injury or death Copyright 2007 by Panasoni...

Page 3: ...STB3 3V Distribution 25 12 Blinks SOS 70 Main CPU VCC Supply A Board 28 Signal Circuit Overview 75 TV_SUB_ON TUNER_SUB_ON 30 Video Process Block Diagram 77 TV_SUB_ON F_STB_ON 32 D Board Block Diagram 79 TV_SUB_ON Relay Drive Circuit 34 Panel Drive TH 42PX75U 81 PFC Circuit 36 Audio Process Block Diagram 83 ACFB Active Clamp Full Bridge Switching Circuit 37 Self Check Function 88 MAIN SUB Voltages ...

Page 4: ...Table of Contents Continued Subject Page Driver Setup Adjustment 96 Initialization Pulse Adjustment 97 Quick adjustment after P C B exchange 98 4 ...

Page 5: ...2007 Panasonic Plasma Line up 5 ...

Page 6: ...Models Comparison 6 ...

Page 7: ...Models Comparison 7 ...

Page 8: ...Models Comparison 8 ...

Page 9: ...PDP HD PDP approx 1 050 000 pixels 1366 768 Full HD PDP approx 2 070 000 pixels Image resolution about twice as high 1080 1920 When compared to the 50PX600 The Full HD plasma panel boasts a total of about 2 070 000 pixels 1920 x 1080 It renders true to life HD images with about twice the resolution of a standard HD panel 9 ...

Page 10: ...10 ...

Page 11: ...10th Generation Plasma Television 11 Board Layout ...

Page 12: ...12 ...

Page 13: ...dressing in the 42 HD models last year when the 9th generation of Plasma TV was introduced The single scan addressing was only used on standard definition models previously For this generation Panasonic has added the 50 models to the list of TV using single scan addressing 13 ...

Page 14: ...TH 42PX75U Board Layout Pictorial 14 ...

Page 15: ...Process Switching Circuit The 2007 42 plasma models have less boards than the previous generation The PA DT DG H and HC boards used on the 2006 42 models are now incorporated within the new A board of the 2007 models 15 ...

Page 16: ...Overall Block Diagram 16 ...

Page 17: ... unit to the AC voltage source the STB5V of the P board is provided to the A board for system control operation The F_STB15V is also provided to the signal switching processing circuit of the A board It remains present for approximately 25 seconds unless the power button is pressed This circuit also receives 15V for audio operation and fan drive for models with fan 3 Panel Drive Circuit The Panel ...

Page 18: ...18 ...

Page 19: ...10th Generation Plasma Television 19 Power Supply ...

Page 20: ...20 ...

Page 21: ...Standby Circuit 21 ...

Page 22: ...pplied to the D board in the Panel Drive Section is not used during standby operation 3 On the other hand when the A board receives the 5V from the Power supply it outputs the F_STB_ON command 4 This command is applied to the power supply board to generate the F_STB15V The F_STB15V is applied to the A board to energize the Signal SW Process Circuit 22 ...

Page 23: ...Standby Circuit 23 ...

Page 24: ...eives the 3 3V it outputs the TV_SUB_ON TUNER_SUB_ON command to the Power MCU IC501 located on the Power Supply board Subsequently the power MCU outputs the following commands 1 Relays ON OFF _ To turn on the circuit that activates on the AC relays The PFC Power Factor Control circuit goes into operation to create the DC voltage needed to power the ACFB circuit 2 VLOW ON OFF _ to turn on the ACFB ...

Page 25: ...s During standby this voltage is not used by the D board On the A board the STB5V is applied to a 3 3V regulator IC5604 to generate the STB3 3V to power the MAIN MICON Genx4 IC1100 The STB3 3V is also connected to the remote receiver IC and the power LED on the K board 25 ...

Page 26: ...ircuit combined with the circuit in the following page is used to explain the reason why the CPU IC9003 on the D board is not active during Standby The transistor Q9014 is on to keep PANEL_STBY_ON low 26 STB5V 2 ...

Page 27: ...IC9011 The output of this IC is controlled by the ON OFF pin Pin 6 The DC level of this pin is determined by the STB3 3V ON OFF circuit During standby pin 6 of IC9011 is low keeping IC9011 off When the power is turned on pin 6 goes high the IC turns on and outputs 3 3V on pin 3 27 STB5V 3 ...

Page 28: ...Main CPU VCC Supply A Board 28 ...

Page 29: ...4 is then applied to pins 31 50 74 78 81 85 and 100 of the CPU IC1100 This turns on the main CPU IC1100 and a high command TV_SUB_ON TUNER_SUB_ON is output on pin 1 This command splits in 2 TUNER_SUB_ON and TV_SUB_ON The TUNER_SUB_ON command together with the STB5V is applied to the SOS detect circuit to monitor the sub voltages generated in the A board The TV_SUB_ON command is applied to the powe...

Page 30: ...TV_SUB_ON TUNER_SUB_ON 30 ...

Page 31: ...ity Under normal operation the TUNER_SUB_ON voltage from pin 1 of the main CPU IC1101 turns on Q3504 When Q3504 is on a low is applied to the base of Q3502 turning it on When Q3502 is on 5V is applied to the emitter and base of Q3503 The transistor remains off until a short circuit or excessive voltage is developed in the supply lines connected to its base When Q3503 is off a low is output to pin ...

Page 32: ...TV_SUB_ON F_STB_ON 32 P P Board ...

Page 33: ... to develop 1 The relay commands high from pins 11 and 12 of IC501 are used to trigger the relays RL402 and RL403 2 A low from pin 16 of IC501 is used to turn on the power factor control IC IC406 to generate the 395V DC 3 A high from pin 15 of IC501 is used to turn on the V low power control IC IC520 to turn on the oscillator in the Active Clamp Full Bridge System circuit 4 A low from pin 18 of IC...

Page 34: ...TV_SUB_ON Relay Drive Circuit 34 ...

Page 35: ... on Q502 to trigger the inrush relay RL403 Approximately 300ms later pin 11 also goes high turning on Q501 to trigger the main relay RL402 300ms later pin 12 goes low allowing for only the main relay RL402 to remain on RL401 is triggered whenever RL402 or RL403 are triggered AC voltage flows through the relays contact the line filter and the bridge rectifier D401 for conversion into DC 35 ...

Page 36: ...when pin 23 is high When pin 16 goes low the diode within the photo coupler IC401 emits light to turn on the photo transistor Pin 4 of IC401 goes low This low is applied to the gate of Q401 turning it on to apply 12V to pin 8 of PFC circuit 36 ...

Page 37: ...ACFB Active Clamp Full Bridge Switching Circuit 37 ...

Page 38: ...ontrol IC IC520 to energize the primary of transformer T402 and allow the switching circuit to drive transformer T404 2 The secondary circuit of transformer T404 outputs the Vsus Vda and 15V voltage sources 3 The 15V is applied to the DC DC converter Q556 The output of Q556 is controlled by pin 4 4 Pin 18 goes low to turn off Q524 When Q524 is off 22V is applied to pin 4 of Q556 turning it on At t...

Page 39: ...MAIN SUB Voltages 39 ...

Page 40: ...are the ON OFF pins When pin 1 is high pin 3 outputs 5V When pin 15 is high pin 13 outputs 9V D3500 monitors the 15V line for OVER VOLTAGE condition If the 15V becomes excessive D3500 conducts to turn on Q3500 When Q3500 is on pin1 and pin 15 go low to disable IC3500 The 9V from pin 13 of IC3500 is applied to the 3 3V DC DC converter IC5600 to generate the SUB3 3V The 9V is also applied to the 1 2...

Page 41: ...F 15V DTV9V SUB5V SOS Detect Circuit 41 ...

Page 42: ...mes When the F STB15V line is shorted the base of Q3503 goes low turning it on When Q3503 is on a high is applied to pin 114 of IC1100 triggering the shutdown operation The same will happen if a short circuit develops in the DTV9V line and the SUB5V line The transistor Q3505 monitors the SUB5V and the DTV9V lines If any of these supply voltages becomes excessive the inline zener diode D3505 or D35...

Page 43: ...Power On Operation 43 ...

Page 44: ... and the F_STB_ON command The PANEL_STB_ON is provided to the D board to turn on the STB3 3V regulator The output voltage is applied to the CPU in the D board The F_STB_ON command is provided to the power supply to develop the F_STB 15V When the CPU on the D board is energized it outputs the PANEL_MAIN_ON command to the power supply This command turns on the power supply circuit that outputs the V...

Page 45: ...Power On 1 45 L H ...

Page 46: ... low to the key input line pin 18 of the CPU IC1100 on the A board The R C receiver receives the power on command of the remote control and outputs the IR data to the amplifier Q2510 of the A board The data is amplified and output to pin 45 of the MPU IC1100 A high from pin 49 of IC1100 enters the base of Q2511 to turn it on As a result the cathode of D2520A goes low causing the illumination of th...

Page 47: ...receiving the power on command the PANEL STB VCC ON pin of the main MPU IC1100 outputs 2 5V to the base of Q4015 turning it on Q4015 outputs a low to turn off Q4014 allowing pin 20 of the connector A5 D5 to go high 47 ...

Page 48: ...48 Power On 3 ...

Page 49: ...pin 20 of connector D5 is applied to the base of Q9044 on the D board turning it on Q9044 outputs a low to turn off Q9046 When pin 6 goes high IC9011 outputs the reset command at pin 1 and the STB3 3V at pin 3 The STB3 3V is applied to the VCC pins of the CPU IC9003 pins 24 39 61 63 68 and 88 The CPU then outputs a high 3 2V at pin 100 The 3 2V is directed to the power supply via pin 11 of connect...

Page 50: ...repeated when the F STB ON command from the A board is applied to pin 23 When the 3 2V PANEL MAIN ON command from the D board is applied to pin 24 of IC501 pin 10 goes high and pin 14 goes low The high from pin 10 turns on the 15V DC DC converter Q555 to output the P15V When pin 14 goes low the Vsus switching circuit is turned on to allow for Vsus and Vda to be output ...

Page 51: ...P15V P5V Circuit 51 ...

Page 52: ...uring standby the relays are closed the PFC circuit is on and pin 15 goes high to turn on the low voltage power control IC520 to drive the oscillator circuit Q408 Q409 Q412 and Q413 When this happens voltages are developed by the secondary circuit The rectified 15V from T404 is applied to the DC DC converter Q555 The output of Q555 is controlled by the voltage on pin 4 The high from pin 10 changes...

Page 53: ...Vsus Vda Circuit 53 ...

Page 54: ...path to turn on the LED within the photo coupler IC507 The light from the LED turns on the phototransistor within the photo coupler and its collector pin 4 goes low to turn off Q540 When Q540 is off the DC voltage from the rectifier D586 is applied to the gate of Q507 turning it on Q507 outputs the VSUS voltage The VSUS voltage is also used to turn on Q527 to output the VDA 54 ...

Page 55: ...rily go from 4 5V to 0V when the power button is pressed Is there 5V at pin 5 of connector A7 when the TV is plugged into the AC line Unplug the TV Disconnect connector A7 Does the TV turn on by itself with no picture and lit LEDs on the SS SC boards when it is plugged into the AC line Check connections and the S K boards Replace The A board Replace The D board Replace The P board Replace The P bo...

Page 56: ... AC relays click after the TV is plugged into the AC line If cable between connectors K1 and A1 is OK Replace the K board Continue from Previous slide NO NO NO Yes Yes Yes Replace The P board Disconnect connector A1 Do the AC relays click after the TV is plugged into the AC line Replace The A board If cable between connectors GS52 and A52 is OK Replace the GS board 56 ...

Page 57: ...10th Generation Plasma Television 57 Shutdown Circuits ...

Page 58: ...58 ...

Page 59: ...SOS Circuit Overview 59 ...

Page 60: ...sult the unit shuts down and the power LED blinks 2 times 3 Blinks SOS IC9807 is a 3 3V regulator located on the D board Its output is monitored by IC9003 If the 3 3V is not present at pin 86 the MPU shuts down the unit The power LED blinks 3 times 5 Blinks SOS Pin 85 of the MPU IC9003 monitors the 5V line During normal operation the transistors Q9051 and Q9052 output a high to pin 85 If the 5V li...

Page 61: ...normal operation pin 8 of connector SS23 outputs a low to pin 91 If the SS board becomes defective a high is provided to pin 91 As a result the unit shuts down and the power LED blinks 8 times 10 Blinks SOS The SUB5V and DT9V sources created on the A board are monitored by IC1100 If they are not present at pin 30 and 34 the MPU shuts down the unit The power LED blinks 10 times 10 Blinks SOS The F_...

Page 62: ... or the 15V lines develops a short to ground transistor Q2301 goes into conduction and applies a high to pin 118 of the MPU IC1100 triggering a SOS condition The power LED blinks 12 times 12 Blinks SOS We have also discovered that 12 blinks of the power LED may also be caused by a defective SS board To determine the source of the shutdown disconnect the connector D5 and connect the unit to the AC ...

Page 63: ...DRV_RST SOS 63 ...

Page 64: ... causes the collector of transistor Q9301 to become low As a result the base voltage of Q9302 also becomes low causing its collector to go high The output voltage is applied to IC9500 and IC9003 as DVR RST When the 5V SENSE circuit does not detect 5V from the C2 board the DVR RST output becomes low The unit goes into shutdown and the power LED blinks 12 times When troubleshooting 5 blinks SOS isol...

Page 65: ...Location of Q9302 65 ...

Page 66: ...Close up View of Q9302 66 ...

Page 67: ...5 Blinks SOS 1 67 ...

Page 68: ...ect the connector SS23 and measure the resistance between pin 12 of the connector C23 and ground The normal resistance is approximately 110000 ohms If the panel is shorted the resistance to ground is very low If the panel is determined to be shorted the left and right side of the panel can be isolated by disconnecting the connector C20 C10 Furthermore the ribbon cables of the panel data electrodes...

Page 69: ...SOS Drive reset 69 ...

Page 70: ...xchange 2 The improper installation of the connectors C11 and C21 may cause vertical lines to appear in the picture The improper connection of the connectors C11 C21 C10 and C20 causes a DVR_RST SOS The power LED blinks 6 times leading one to believe that there is a problem in the audio output circuit ...

Page 71: ...12 Blinks SOS 71 ...

Page 72: ...5V source to 12V for connection to the audio power amplifiers 3 The diode D2303 and transistor Q2301 monitor pin 5 of the power amplifiers for excessive current drain If a short circuit develops transistor Q2301 goes into conduction and outputs a high to pin 118 of the MPU IC1100 triggering an SOS condition 4 A short circuit of the 15V line causes the diode D2301 to go into conduction As a result ...

Page 73: ...10th Generation Plasma Television 73 Signal Processing ...

Page 74: ...74 ...

Page 75: ...Signal Circuit Overview 75 ...

Page 76: ...rast color tint etc The PEAKS firmware of the unit also resides in this board The RGB output of the A board passes through an LVDS Low Voltage Differential Signaling transmitter for conversion into serial data The output signal is then applied to the D board The D board is responsible for displaying the picture It provides the scan sustain and data drive signals to address the panel The scan pulse...

Page 77: ...Video Process Block Diagram 77 77 ...

Page 78: ...f the tuner is output in the form of an IF Intermediate Frequency signal IC8302 contains a detector circuit that retrieves the Transport stream from the IF signal The transport stream then enters the DTV I F Interface section of IC8001 where the video signal is extracted and converted to YUV data The output is provided to the Video Input I F for selection The JPEG data of the SD card enters the JP...

Page 79: ...D Board Block Diagram 79 ...

Page 80: ...t converter that changes the resolution of the signal to match the size of the panel It also contains the Plasma AI Adaptive brightness Intensifier circuits that analyzes the APL for the distribution of dark and bright components IC9900 subsequently converts the picture data into the 10 11 or 12 subfields data to feed the two C boards The C boards are buffer boards that are used to distribute data...

Page 81: ...PULSE SUSTAIN ELECTRODE 768Line 42 HD C1 C2 Drive IC 2 inside C11 C21 SC 20 C 23 SS23 SU Board IC6901 IC6906 SHIFT REGISTER UPPER SD Board IC6951 IC6956 SHIFT REGISTER LOWER CB1 CB2 CB3 CB4 CB5 CB6 CB7 CB8 D IC9500 DATA Processor Discharge Control IC9900 D 31 D 32 SC 20 VIDEO DATA SCAN CONTROL PULSE SUS CONTROL PULSE D 20 C Board IC7XXXX BUFFER IC7101 IC7102 IC7103 IC7104 IC7105 IC7201 IC7202 IC72...

Page 82: ... for converting the serial data output of the SC board into parallel data to drive the panel Each board drives one half of the panel horizontally The SS board is responsible for the generation of the sustain pulses Sustain pulses are used to initialize and control the brightness of the panel Data Drive IC9900 memorizes the 10 bit data into two field data to drive the left and right side of the pan...

Page 83: ...Audio Process Block Diagram 83 83 ...

Page 84: ...8302 contains a detector circuit that retrieves the transport stream from the IF signal The transport stream then enters The DTV I F Interface section of IC8001 where the audio signal is extracted and converted to serial data The output is provided to the switch located inside IC2106 The output of the switch enters the Audio Process section of the IC Volume bass treble and balance adjustments of t...

Page 85: ...85 ...

Page 86: ...10th Generation Plasma Television 86 Adjustments ...

Page 87: ...87 ...

Page 88: ...the TV for 5 seconds or disconnect the AC cord from the wall outlet To Exit the Self Check Mode Press and hold the Power button on the TV for 5 seconds or disconnect the AC cord from the wall outlet TV volume down OK on remote only does a basic IC self check It does NOT restore the unit to factory shipping settings It does not clear channel programmed settings picture settings channel labels LOCK ...

Page 89: ...Self Check menu appears on screen Then disconnect the AC cord from the wall outlet To Reset the Unit turn the TV on and while pressing the VOLUME button on the main unit press the Menu button on the remote control for more than 3 seconds The Self Check menu appears on screen Then disconnect the AC cord from the wall outlet Note All customer programmed parameters will be erased 89 ...

Page 90: ...Self Check Menu 90 ...

Page 91: ...Check point 91 ...

Page 92: ...e times within 3 seconds To enter the Serviceman Mode turn the TV on and while pressing the VOLUME button on the main unit press the RECALL button of the remote control three times within 3 seconds To exit the Serviceman Mode Press the Power button on the TV or the Remote Control To exit the Serviceman Mode Press the Power button on the TV or the Remote Control 92 ...

Page 93: ...nd 1 button Main items Selection in forward direction 2 button Main items Selection in reverse direction 3 button Sub items Selection in forward direction 4 button Sub items Selection in reverse direction VOL button Value of sub items change in forward direction in reverse direction ...

Page 94: ...Adjustment Sub Menu 94 ...

Page 95: ... the main adjustment menu and press the 3 or 4 button of the remote control to select the desired pattern To exit the Serviceman Mode Press the Power button on the TV or the Remote Control To exit the Serviceman Mode Press the Power button on the TV or the Remote Control 95 ...

Page 96: ...re controls as follows Picture menu Vivid Normal Set Aspect Full Caution 1 Perform the Vsus adjustment 2 Confirm the voltage level of VSCN This should be done after the adjustment of Vad which should be 105V When Vad 105V Vscn voltage is 35V 4V Note See the panel label for voltages that are not listed in the service manual 96 ...

Page 97: ... Adjustment 1 Input a 100 White signal to the unit 2 Set the picture controls as follows Picture menu Vivid Normal Set Aspect Full 3 Connect an Oscilloscope to test point TPSC1 Using VR6602 adjust T2 for 195 10µ Sec 97 97 ...

Page 98: ...Quick adjustment after P C B exchange 98 1 Caution Wait 1 minute for the electrolytic capacitors to discharge before removing any PCB from the unit 2 Quick adjustment after P C B or Panel exchange 98 ...

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