Technical description and composition of the LG 40LF570V TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 40LF570V
Chassis / Version: LD55T
Panel: HC400DUN-VCKN1-214X
LED backlight: DRT4.0 REV0 7 A / B-Type SVL400
LED driver (backlight): integrated into PSU
PWM LED driver: LC5901
Power Supply (PSU): EAX66163001 (1.6) EAY63630401
PWM Power: MAP8800, SSC3S901
MOSFET Power: MMP60R360P
MainBoard: EAX66203805 (1.2) EBU63186604
IC MainBoard: CPU: LGE2136, SPI Flash: MX25L8035EM2I, EEPROM: 24C256
Tuner: TDJM-G301D p / n: EBL61560001
Specifications 40LF570V
LG 40LF570V
General repair guidelines for TV LCD LED
Possible manifestations of defects
- LG 40LF570V does not turn on, the indicators on the front panel do not light or flash. The TV does not respond to the control buttons and the remote control.
In such cases, the malfunction should be sought first in the EAX66163001 power supply module. It is necessary to measure its output voltages and, in case of their absence, check the serviceability of power switches (MMP60R360P) and rectifier diodes in the converters for possible breakdown.
In case of diode breakdowns in the secondary circuits, the converter can operate in emergency short-circuit mode without output voltages, and during short circuit in the power elements of the primary circuit, the mains fuse and / or current sensor at the source of the key usually breaks.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damping circuits, as well as in Negative Stabilization Feedback. PWM microcircuits MAP8800, SSC3S901 are usually checked by replacing with new, 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.
Usually in such cases, a malfunction is detected in the backlight nodes of the LED panel. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
To check the LED strips, to open all the transitions of the LEDs, several tens of volts or more are needed, it is best to use a current source for such purposes. The breakage of several PN junctions connected in series cannot be detected with a multimeter or tester. In such cases, it is necessary to open the panel and check each LED. If your multimeter cannot open the LED transitions in forward bias, you can sometimes detect the presence of a PN junction of the protective zener diode by connecting the probes in the opposite direction. If the zener diode is broken or broken in short-circuit, then the LED is faulty and needs to be replaced.
- The TV does not turn on, does not respond to the remote control. The indicator blinks or signals standby mode.
Repair or diagnostics of the EAX66203805 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). If it is not possible to replace the MB board (SSB), you need to check the health of its elements - CPU: LGE2136, SPI Flash: MX25L8035EM2I, EEPROM: 24C256. Defective components should be replaced.
If the TV works normally from external devices, but does not tune into television channels, the TDJM-G301D p / n tuner may malfunction: EBL61560001. 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.
Owners and users of the LG 40LF570V TV should remember that self-repair without special knowledge, skills and qualifications can be fraught with negative consequences that can lead to complete non-repairability of the device!
schematic diagram -------------> LG 40LF570V-ZA Chassis LD55T
The appearance of the MainBoard EAX66203805 is shown in the figure below:EAX66203805
EAX66203805 can be used in TVs:
LG 32LF564U (Panel LC320DXE (MG)(A3)), LG 42LF550V (Panel LC420DUE (MG)(A6)), LG 32LF560U ZB (Panel NC320DXN VSBP5 ), LG 42LF560V (Panel LC420DUE (MG)(A3)), LG 32LF562V (Panel NC320DUN-VBBP3 (EAJ63171201)), LG 32LF564V (Panel NC320DUN VBBP3), LG 32LF560V (Panel NC320DUN-VBBP3), LG 49LF620V 49LF620V-ZB (Panel LC490DUE (MG)(P2)), LG 42LF551C (Panel LC420DUE-MGA6).
The appearance of the power supply
Main features of the device LG 40LF570V:
Installed matrix (LED-panel) HC400DUN-VCKN1-214X.
To power the backlight LEDs, a converter is used, combined with the power supply, controlled by the LC5901 PWM controller.
The necessary supply voltages for all nodes of the LG 40LF570V TV are generated by the EAX66163001 power module or its analogs using MAP8800, SSC3S901 microcircuits and power switches of the MMP60R360P type.
MainBoard - the main board (motherboard) is an EAX66203805 module, using CPU chips: LGE2136, SPI Flash: MX25L8035EM2I, EEPROM: 24C256 and others.
Tuner TDJM-G301D p / n: EBL61560001 provides the reception of television programs and tuned to channels.