LG
Model: 47LD650
Chassis / Version: LB03B / LD03B
Panel: LC470WUG (SC) (A1)
Inverter (backlight): integrated into PSU
PWM Inverter: BD9270F
MOSFET Inverter: 2SK3868
Trans Inverter: LIF47-100L NYB-003
Power Supply (PSU): EAX61289601 / 12 REV1.2 - LGP47-10LF
PWM Power: STR-W6053N, R2A20112 (PFC 16pin)
MOSFET Power: 13NM60N
MainBoard: EAX61531908 (4) 10.03.22L.E.S
IC MainBoard: Scaler: LGE3556C, LGE7378B-LF, SDRAM: K4B1G1646E-HCH9, Video Processing: TDA19997HL / C1, ULF: NTR-7100, flash Nand: SAA35042620 Ver.3.5.7
Tuner: TDFR-G135D
Control: AKB73715650
Specifications 47LD650
LG 47LD650
General recommendations for repairing TV LCD
Repair and diagnostics of any electronic device, in particular LG 47LD650, it is advisable to start with a careful external examination of internal and external elements. Based on visible external changes in the state of the components, it is often possible to determine the direction of the troubleshooting before making the necessary measurements. Electrolytic capacitors of filters with a swollen casing, as well as ring cracks formed in the soldered leads of heating elements, or a layer of coal on burnt resistors sometimes tell the repairman the causes of the malfunction and possible consequences.
In cases where the LG 47LD650 TV does not turn on, does not respond to the remote control and buttons, no indicators on the front panel light up or blink, and there are no sounds and no signs of operability when turning on, the EAX61289601 / 12 REV1 power supply module is most likely to be faulty. 2 or there is no standby power. In the absence of swollen filter capacitors of the secondary rectifiers, the power supply diagnostics should be started by checking the fuse and, if it is broken, it is first necessary to check all the power semiconductor elements of the primary circuit - AKB73715650 diodes and transistors for the possibility of an avalanche or thermal breakdown.
The reasons for the breakdown of the power switch in switching power supplies (IIPS) can be different, for example, a malfunction of semiconductor cells or electrolytic capacitors in the stabilization circuits of the primary circuit, as well as a failure in the operation of the PWM regulator chip STR W6053N or breakage of resistors in its bundle.
In cases where the LG 47LD650 TV has lost an image, and the sound is there and all the other functions are functional, there is a possibility of a malfunction of the inverter (converter for powering the backlight). When you turn on the TV, the image may appear briefly and immediately disappear. It must be borne in mind that with such manifestations, the lamps themselves also fail, the malfunction of which can be detected by replacement, by connecting to the connectors for diagnostics that are known to be serviceable and suitable in power. All necessary precautions must be observed when disabling the inverter protection during diagnostics and not leaving it disconnected after the repair is completed.
When trying to repair the motherboard, you should first check the serviceability of linear stabilizers or power converters of microcircuits and, if necessary, update the software (software). In cases of complex repairs of MB (SSB) and with the necessary skills and equipment, sometimes it may be necessary to replace its Scaler chips: LGE3556C, LGE7378B-LF, SDRAM: K4B1G1646E-HCH9, Video Processing: TDA19997HL / C1, ULF: NTR-7100, flash Nand: SAA35042620 Ver.3.5.7 and other possible defective components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
If the TV works normally from external devices, but does not tune into television channels, the TDFR-G135D tuner may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding conclusions. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus. Sometimes the cause of the inoperability of the tuner may be a software failure.
- Once again, we remind TV users: you should not make attempts to repair it yourself without the appropriate knowledge, experience and the necessary qualifications! Trust the repair only to professionals with sufficient experience in the field of electronic equipment repair.
External manifestations may be different - the tuner or external inputs do not work, or the TV does not turn on, for example, the control lamp blinks or hangs on the screen saver.
If, when the processor warms up, performance is restored, in such cases a reball can sometimes help. Then there is the opportunity to extend the life of the TV with the help of an additional heat sink or cooler.
When replacing the processor, it should be borne in mind that they are discontinued and all LGE3556C, which sellers ALIexpress send, in most cases control units, are often already faulty.
Service manual and schematic diagram ---------------> LG 47LD650 Chassis LB03B.
CHASSIS : LD03B; MODEL : 47LD650, 47LD680, 47LD650, 47LD680-ZC, 47LD650N, 47LD650N-ZC, 47LD651, 47LD690, 47LD651, 47LD690-ZB
The appearance of the MainBoard EAX61531908 is shown in the figure below:
EAX61531908
PSU Advanced
The 47LD650 model uses the EAX61289601 / 12 REV1.2 power supply unit - LGP47-10LF using the PFC (Power Factor Correction) node - an active filter of higher harmonics of the consumed current. In fact, it is a boost converter based on the PWM controller R2A20112 16pin, which eliminates the charge current of the electrolytic capacitor of the rectifier filter directly from the network through open diodes when its charging current is determined by its reactance.
As a result of the operation of the converter, the envelope of the high-frequency pulses of the input current of the converter will repeat the shape and phase of the input voltage. The health of the PFC node can be indirectly judged by the presence of an increased constant voltage (about + 380V) on the capacitor of the rectifier network in operating mode.
The appearance of the power supply
Main features of the device LG 47LD650:
Installed matrix (LCD panel) LC470WUG (SC) (A1).
To power the backlight, a converter is used, combined with the power supply, controlled by the BD9270F PWM controller. The transformer LIF47-100L NYB-003 is installed in the inverter converter. As power elements of the inverter, keys of the 2SK3868 type are used.
The necessary supply voltages for all nodes of the LG 47LD650 TV are generated by the EAX61289601 power module or its analogs using STR-W6053N, R2A20112 (PFC 16pin) microcircuits and 13NM60N power switches.
MainBoard - the main board (motherboard) is an EAX61531908 module, using Scaler microcircuits: LGE3556C, LGE7378B-LF, SDRAM: K4B1G1646E-HCH9, Video Processing: TDA19997HL / C1, ULF: NTR-7100, flash Nand: SAA35042620.3 .7 and others.
The TDFR-G135D tuner provides TV reception and channel tuning.