Technical description and composition of the LG 49UB820V TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 49UB820V 49UB820V-ZH
Chassis / Version: LD48V
Panel: LC490EQE (XG) (F2)
T-CON: 6870C-0502C
LED driver (backlight): integrated into PSU; 74.9V 1.2A (55 inch)
Power Supply (PSU): EAX65613901 EAY63149401
PWM Power: ICE3BR4765JZ (Standby DIP-7), IW7025, 2843B
MainBoard: EAX66085703 EBT63174502
IC MainBoard: LGE7411 / LGE4331B4, 25L320BE, AT24C256C, H5TQ4G63AFR, NTP7514
Tuner: TDJM-G251D
Specifications 49UB820V
LG 49UB820V
General repair guidelines for TV LCD LED
Possible malfunctions
- The LG 49UB820V TV does not turn on, does not respond to the remote control and the control panel buttons, the indicators do not light or flash.
In some of these cases, a malfunction is detected in the EAX65613901 power module. It is necessary to verify the presence of its output voltages and, if they are completely absent, check the power switches and rectifier diodes for a probable short circuit.
In case of breakdowns of semiconductors in secondary circuits, the converter can usually operate abnormally in short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse often breaks.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can put it out of operation in key mode or provoke an excess of the maximum current or voltage. These can be circuits supplying the PWM controller, damping or frequency-setting circuits, or elements of OOS (negative feedback) in the stabilization circuit. PWM controllers (PWM) ICE3BR4765JZ (Standby DIP-7), IW7025, 2843B, in the absence of external damage and short circuit between the terminals, are checked by replacing with obviously good ones.
- There is no image, there is sound, it responds to the remote control, the channels are switched. In some cases, the image appears when you turn on and immediately disappears.
In such cases, the most likely malfunction of the LED backlight elements. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
When diagnosing, it is necessary to take into account that it is impossible to check the open in the chain of LED lines without disassembling the panels using a tester or multimeter. To open all PN junctions connected in series, a voltage of the order of several tens of volts is required, and ideally, a current source. By opening the panel, each LED can be checked separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect probes in the forward direction to it. In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as a health indicator. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
- The indicator on the front panel blinks, the TV does not turn on in operating mode, it does not respond to the remote control.
Repair or diagnostics of the EAX66085703 motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). Sophisticated MB board repair (SSB) is in some cases possible and practiced by repairmen. To do this, check and, if necessary, replace the elements LGE7411 / LGE4331B4, 25L320BE, AT24C256C, H5TQ4G63AFR, NTP7514. BGA chip malfunctions are usually easy to detect by warming up.
If the TV works normally from external devices, but does not tune into television channels, the TDJM-G251D 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.
Attention TV owners! Self-repair attempts by LG 49UB820V are not recommended by the manufacturer and can lead to serious negative consequences!
LG 49UB820V, Chassis-L * 48V. Panel: LC490EQE (XG) (M1), Main Board-EAX66085703 (1.0) EBT63174502 SPI Flash: W25Q32BV
FIRMWARE SPI FLASH ------------> LG 49UB820V, Main: EAX66085703, LC490EQE(XG)(M1)
The appearance of the MainBoard EAX66085703 is shown in the figure below:EAX66085703
EAX66085703 can be used in TVs:
LG 42UB820V 42UB820V-ZH.ARUWLJU (Panel LC420EQE (PG)(M1)), LG 49UB830V (Panel LC490EQE (XG)(F2)), LG 49UB820V 49UB820V-ZH (Panel LC490EQE (XG)(F2) ), LG 40UB800V 40UB800V-ZA (Panel V400DK1-KE1).
The appearance of the power supply
Main features of the device LG 49UB820V:
Installed matrix (LED-panel) LC490EQE (XG) (F2).
The matrix control uses the Timing Controller (T-CON) 6870C-0502C.
To power the backlight LEDs, a converter is used, combined with a power supply.
The necessary supply voltages for all nodes of the LG 49UB820V TV are generated by the EAX65613901 power module, or its analogs using ICE3BR4765JZ (Standby DIP-7), IW7025, 2843B microcircuits.
MainBoard - the main board (motherboard) is an EAX66085703 module, using chips LGE7411 / LGE4331B4, 25L320BE, AT24C256C, H5TQ4G63AFR, NTP7514 and others.
The TDJM-G251D tuner provides TV reception and channel tuning.
