Technical description and composition of the LG 37LC41 TV, panel type and applicable modules. The composition of the modules.LG
Model: 37LC41 ZA
Chassis / Version: LP78A / B
Panel: LC370WX4-SLA1
Lamp backlight: 16 Lamp EEFL
T-CON: 6870C-0158A
Inverter (backlight): integrated into PSU
PWM Inverter: FAN7382, MSC1691AI
MOSFET Inverter: SD20N60
Power Supply (PSU): EAX32268301 / 8 PLHL-T603A rev: 1.0 EAY34796801
PWM Power: 5501A, ICE3B1565J, FAN7601
MOSFET Power: 04N60C3
MainBoard: EAX32572506 // EAX32572502
IC MainBoard: ANX9021, TPA3107D2, STMAV340, VST7993P, 24C32
Tuner: TAFT-W005D
Specifications 37LC41
LG 37LC41
General recommendations for repairing TV LCD
Possible malfunctions
- The LG 37LC41 TV does not turn on and does not show any signs of turning on, it does not respond to the control buttons or to the remote control.
Often in such cases, the EAX32268301 power module is faulty. It is necessary to measure its output voltages, and in case of their absence, check the operability of the power switches of the converters and rectifier diodes for the probability of a short circuit.
In case of any breakdown of semiconductors in the secondary circuits, the converter can usually work normally in emergency short circuit mode. There are no output voltages. And during short circuit in the power elements of the primary circuit, as a rule, the mains fuse breaks and less often the current sensor at the source of the key.
Mos-Fet power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. 5501A PWM controllers, in the absence of visible damage or open faults between the terminals, are checked by replacing them with new ones, or obviously working.
- There is no image, but there is sound and reaction to the remote control. Or for a second, the image may appear immediately after switching on.
The defect can be caused by problems in the nodes or elements of the backlight of the display, or in the power supply of the lamps or inverter. If all the electrolytic capacitors of the filter according to the power supply of the inverter are working, make sure that the lamps are working, then you need to check the converter keys and the secondary windings of the transformers.
If in diagnosing a malfunction, it is necessary to disable the inverter protection, there is a risk of failure of the power elements of the inverter, and special care is required during work, and after they are finished, it is necessary to restore the protection circuits for further safe operation of the TV by the owner in normal mode.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the EAX32572506 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). Board repair and replacement of ANX9021, TPA3107D2, STMAV340, VST7993P, 24C32 microcircuits are carried out with the necessary equipment, and the corresponding element base. Faults associated with the application of BGA processor soldering technologies can be localized by the heating method.
Before replacing the TAFT-W005D tuner, if there is no tuning to the channels, you must first check the software and the supply voltage at its terminals. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus
Attention to users! Self-repair of the LG 37LC41 TV without the appropriate qualifications and necessary experience can lead to its complete non-repairability!
FIRMWARE FOR MICRONAS (VCT7993P) --------------------> LG 37LC41-ZA LP78A/B
The appearance of the MainBoard EAX32572506 is shown in the figure below:EAX32572506
EAX32572506 can be used in TVs:
LG 32LC43-ZE (Panel LC320WX6 SL A3), LG 32LC7RC TA (Panel LC320WX6 (SL)(A3)), LG 32LC41 (Panel LC320WX4 (SL)(D2)), LG 37LC41 ZA (Panel LC370WX4-SLA1).
The appearance of the power supply
Main features of the device LG 37LC41:
Installed matrix (LCD panel) LC370WX4-SLA1.
The matrix control uses the Timing Controller (T-CON) 6870C-0158A.
To power the backlight, a converter is used, combined with a power supply, controlled by a FAN7382, MSC1691AI PWM controller. As power elements of the inverter, keys of the type SD20N60 are used.
The necessary supply voltages for all nodes of the LG 37LC41 TV are generated by the EAX32268301 power module or its analogs using 5501A, ICE3B1565J, FAN7601 chips and 04N60C3 type power switches.
MainBoard - the main board (motherboard) is an EAX32572506 module, using ANX9021, TPA3107D2, STMAV340, VST7993P, 24C32 and other chips.
The TAFT-W005D tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: LG.Philips LCD
Model: LC370WX4-SLA1
Type: a-Si TFT-LCD, Panel
Diagonal size: 37 inch
Resolution: 1366x768, WXGA
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 819.6x460.8 mm
Surface: Antiglare (Haze 13%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 6 (Tr + Td)
Frequency: 60Hz
Lamp Type: 16 pcs EEFL Embedded (Inverter)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 12.0V