DP驱动电路分析(以TH-42PA20C为例).ppt

TH-42PA20C驱动电路分析,5-1ENERGYRECOVERYCIRCUIT（能量回收电路）,C(PANEL屏幕),S1,L,1/2Vo,Vo,S2,S3,Vo,1/2Vo,S1,S2,S3,ON,ON,ON,ON,为了节约电能，用此电路,产生维持脉冲,5-2.ENERGYRECOVERYCIRCUITforSCBOARD（能量回收电路-SC板）,CHASSIS（型号）,(42寸),S1,Q6621,Q6622,Q6623,Q6624,Q6625,Q6626,DISCHARGE（放电）,CHARGE（充电）,S2,S3,Q6601,Q6602,Q6603,Q6604,Q6605,Q6606,Q6607,Q6608,L,L6611,L6612,L6613,L6614,L6615,L6616,C(1/2V0),C6621,C6622,C6623,C6624,C6625,C6626,V0,Vsus（维持电压）,CHECKLED（检测指示灯）,D6583（不亮则SC板有问题）,5-3.ENERGYRECOVERYCIRCUITforSSBOARD（能量回收电路-SS板）,CHASSIS（型号）,42寸,S1,Q6721,Q6722,Q6723,Q6724,Q6725,Q6726,DISCHARGE（放电）,CHARGE（充电）,S2,S3,Q6701,Q6702,Q6703,Q6704,Q6705,Q6706,Q6707,Q6708,L,L6711,L6712,L6713,L6714,L6715,L6716,C(1/2V0),C6721,C6722,C6723,C6724,C6725,C6726,C6727,C6728,C6729,C6730,V0,Vsus,CHECKLED（检测指示灯）,D6785(不亮则SS板有问题）,5-4SCAN&SUSTAINSIGNAL,SCANDRIVESIGNAL,SUSTAINDRIVESIGNAL,+,5-5-1SCANSIGNAL,VSET,SCANPULSEonSU/SD,SCANGROUND,SUSTAINPULSE,VSETBASE(vsus),+,=,VSCAN,VBK,VAD,SETUP,SC,5-5-2SCboard,VSUS,1/2V0,ENERGYRECOVERYCIRCUIT,S2,S3,S1CHARGE,S1DISCHARGE,L,VBK,BK,VADGEN.,VSET2GEN.,VSETREGURATOR,VSCNGENELATOR,VSUS,15V,SCOUT(VF0),SCGND(VF),Q6520-Q6521,Q6511,Q6512,Q6551Q6552,Q6553Q6555,Q6522-Q6527,Q6542-Q6547,Q6641,42,Q6601Q6602,Q6605Q6606,Q6621,Q6624,175V,28V,-90V,155V,175V,CSH,CSL,CMH,CML,CPH,n-CPH,CEL,CBK,N-CEL,SCSU,N-CE,CE,CMH,CML,CBK,CPH,CPH,CSH,CSL,Vset218V,Vsus170V,Vbk155V,CEL,CEL,SC,SC,Vad90V,SCSU,M/I,M/I,IC6401IC6404IC6405IC6408,Vscn28V,Vset,Vsus,Vbk,Vad,CMH,CPH,CEL,CML,CSH,CSL,CBK,SC,Vf,Vfo,5-5-3SCboard,S1,S2,S3,480lines,SDModels,5-5-4SUSTAINSIGNAL,VE,SUSTAINPULSE,VE2,SS,5-5-5SSboard,VSUS,1/2V0,ENERGYRECOVERYCIRCUIT,S2,S3,S1CHARGE,S1DISCHARGE,L,VEREGULATOR,VSUS,VE(5V),SSOUT,Q6745,Q6746,C6747,Q6741Q6742,+,-,158V,UMH,Q6724,Q6721,Q6701Q6702,Q6705Q6706,175V,175V,UML,USH,USL,UEH,n-VEL,VEL,SUSTAINPULSE,UEH,UEL,UEL,UML,UMH,USH,USL,VE158V,VE2155V,Vsus170V,5-5-6SSboard,42”/37”SD/42”HD,5-6-1SCANPULSEOUTPUT(SU&SDBoard),240PULSES,240PULSES,SHIFTRESISTOR,SCANPULSEOUTIC,x4x2,SU,SD,240PULSES,240PULSES,IC6401IC6404IC6405IC6408,Upperside48BIT+64BIT3,AddressPulse,FCLK,FCL,FSI,PRO,1480,64BIT3+48BITBottomside,FCLK,FCL,FSI,480Pulses,A,B,FromPROPulse,FromB,FromB,From,Vf,Vfo,5-6-2SCANPULSEOUTPUTAddressPulse(SU&SDBoard),SUS,SDModels,5-6-3SCANPULSEOUTPUT(SU&SDBoard),SD板：IC6405-64线IC6406-64线IC6407-64线IC6408-48线,SU板：IC6401-48线IC6402-64线IC6403-64线IC6404-64线,5-8-1故障检测,SC板主要电压和驱动波形：Vsus=170VVbk=155VVset=218VVscn=30VVad=-90V,SS板主要电压和驱动波形：Vsus=170VVe=150VVda=67V,SC/SS板电压与图像变化情况,5-8-2故障检测,主要故障现象：保护，指示灯闪烁2次。图像负像或有斑点图像水平拉丝图像水平一条线或宽带,5-8-3修理实例,故障现象：保护，指示灯闪烁2次。,分析：指示灯闪烁2次，通过前面讲述的修理流程，判断是SC板。在SC板上有5路保护，输出2路保护信号。D6584是1/2V0的保护控制。D6468是VF0的保护控制。D6459是VF的保护控制。D6470是VSCN的保护控制。D6480是VAD的保护控制。,检修经过：开机测量D6584、D6468、D6459、D6470、D6479正端的瞬间电压。检测D6479时发现正端瞬间有电压变化。估计是VAD电压异常造成保护。测量VAD发生器Q6471、D6474、T6471、IC6471，发现IC6471异常。更换IC6471，故障解除。,特别提示：对于VAD和VSCN引起的保护，我们可以仅仅提供15V电源来进行修理。,