Technical description and composition of the LG 42LM580T-ZA TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 42LM580T-ZA
Chassis / Version: LD21B
Panel: LC420EUE (SE) (F1)
LED backlight: 6922L-0016A 6916L0936A (Cool), AGS416 CF, 42 V12 Edge REV1.1 1 6920L-0001C
T-CON: 6870C-0401B
LED driver (backlight): integrated into PSU; 67V 0.78A
PWM LED driver: R5F100BCAFP, AAT2430AISX
MOSFET LED driver: PHT4NQ10LT * 4
Power Supply (PSU): EAX64427101 (1.4)
PWM Power: FAN7930BG (PFC), L6599AD (PWM Resonant), STR-A6059
MOSFET Power: STF13NM60N, STF10NM60N, FDT86106LZ
MainBoard: EAX64909901 (1.0) - EBR75084305, SAA35916785, SAA35948821
IC MainBoard: LGE2111A-T8, NAND FLASH: H27U1G8F2BTR / BC - 1 Gbit (128M x 8 bit), SPI: W25Q80, EEPROM: 24C256, AUDIO: STA380BWE
Tuner: TDSN-G301D EBL61080001
Control: AKB73615307; IR: EBR74986703, LM35-55, MB32B00, 1BF-3010B
Specifications 42LM580T
LG 42LM580T-ZA
General repair guidelines for TV LCD LED
Repair of all electronic devices, including the LG 42LM580T-ZA TV, it is advisable to start with an external examination of its external and internal elements. Specific external damage to some elements can sometimes indicate further actions to determine the malfunction of the TV and localize the defect before the necessary measurements are taken. Swollen electrolytic or cermet capacitors, charred resistors, ring cracks in the soldered terminals of the elements - all this can significantly help the master to determine the causes and consequences of the malfunction of the TV.
If the LG 42LM580T-ZA does not turn on, no control lights on the front panel light up or blink, therefore, there is a very high probability of a malfunction of the EAX64427101 power supply module (1.4). In some cases, only the processor power regulator may be faulty. In the absence of swollen filter capacitors of the secondary rectifiers, the diagnostics of the power supply 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 - diodes and transistors for the possibility of an avalanche or thermal breakdown.
It should be borne in mind that in the practice of repair it is extremely rare that key transistors in switching power supplies (SMPS) fail for no reason that should be sought by checking other components, for example, a breakdown of the key can provoke faulty elements of the damper circuits, or dried electrolytic capacitors or dangling primary resistors BP circuits involved in the stabilization process. In this case, all the semiconductor elements of the strapping of the PWM regulator chip FAN7930BG, L6599AD, STR-A6059, FDT86106LZ, D10100CT, which should be checked by replacement, are subject to verification.
If the LG 42LM580T-ZA does not have an image, but there is sound and the TV is controlled from the remote control, a malfunction in the backlight circuits of the panel is likely. The LEDs or the power converter - LED driver may be faulty. Often in such cases, when you turn on the TV, an image appears and immediately disappears. First of all, it is necessary to verify the operability of the electrolytic capacitors of the rectifier filter supplying the LED driver, and check the LEDs, connecting obviously known good diagnostics.
Often in the absence of backlighting, disassembling the panel is required. It is necessary to check the serviceability of the transitions of the LEDs, as well as the reliability of the contact connections in the rulers and connectors.
It is impossible to check the LED line for breaks without disassembling the panel with a multimeter or tester. For these purposes, it is necessary to open all series-connected PN junctions and a voltage of the order of tens of volts will be required, and ideally, a current source.
Attention to the owners! Attempts at self-repair of the LG 42LM580T-ZA TV are not recommended by the manufacturer and can lead to serious negative consequences!
SCHEMATIC DIAGRAM ---------> LG 42LM580S, 42LM580T, 42LM585S, 42LM580S, 42LM580T-ZA, 42LM585S-ZD Chassis LD21B.
PSU SCHEMATIC DIAGRAM ---------> LG EAX64427101 EAY62608901 LGP4247L-12LPB PLDF-L103A
To reduce the backlight current in LED drivers with the AAT2430AISX controller, increase the resistance of the resistor from terminal 50 (ISET) to the housing, for example, from 3 KOhm to 4.7 KOhm. Currents will proportionally decrease in each of the 16 channels. With a parallel connection of channels, currents are summed.
The appearance of the MainBoard EAX64909901 is shown in the figure below:EAX64909901
EAX64909901 can be used on TVs:
LG 42LM580T-ZA (Panel LC420EUE (SE)(F1)), LG 42LM340T (Panel LC420DUN (SE)(U3)), LG 32LM580T (Panel LC320EUN (SE)(F3)), LG 42LM585T ZD (Panel LC420EUE (SE)(F1)), LG 42LM615T (Panel LC420EUE (SE)(F1)), LG 42LS560T 42LS560T-ZC (Panel T420HVN01.1).
PSU Advanced
According to the conditions of compliance with modern world standards for household switching power supplies, the EAX64427101 module provides for the use of a Power Factor Correction unit. The PFC circuit is a flyback converter based on the FAN7930BG PWM controller. The reactance of an electrolytic capacitor of a line filter at a frequency of 50-60 Hz is usually not more than 20-30 ohms and its charge directly from the network through open diodes could reach tens of amperes per pulse if no filtering were applied.
As a result of the PFC conversion, an increased voltage on the capacitor (about 380V) cannot directly open the rectifier diodes, on the anode of which the voltage will always be slightly less (about 300V) and then its charging current will always be limited by the elements of the PWM controller. As a result, the envelope of the high-frequency pulses of the consumed current will repeat the shape and phase of the input sinusoidal voltage. The presence of an increased voltage (+ 380V) on the network capacitor indicates the serviceability of the PFC node.
The appearance of the power supply
Main features of the device LG 42LM580T-ZA:
Installed matrix (LED-panel) LC420EUE (SE) (F1).
The matrix control uses the Timing Controller (T-CON) 6870C-0401B.
To power the backlight LEDs, a converter is used, combined with a power supply unit, controlled by a PWM controller R5F100BCAFP, AAT2430AISX. As power elements of the LED driver, keys of the type PHT4NQ10LT * 4 are used.
The necessary supply voltages for all nodes of the LG 42LM580T-ZA TV are generated by the EAX64427101 power module or its analogs using FAN7930BG (PFC), L6599AD (PWM Resonant), STR-A6059 chips and power switches of the STF13NM60N, STF10NM60N, FDT86106 type.
MainBoard - the main board (motherboard) is an EAX64909901 module using LGE2111A-T8 chips, NAND FLASH: H27U1G8F2BTR / BC - 1 Gbit (128M x 8 bits), SPI: W25Q80, EEPROM: 24C256, AUDIO: STA380BWE and others.
The TDSN-G301D EBL61080001 tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: LG Display
Model: LC420EUE-SEF1
Type: a-Si TFT-LCD, Panel
Diagonal size: 42 inch
Resolution: 1920x1080, FHD
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 930.24x523.26 mm
Surface: Antiglare (Haze 1%), Hard coating (3H)
Brightness: 360 cd / m²
Contrast Ratio: 1400: 1
Display Colors: 16.7M (8-bit), CIE1931 68%
Response Time: 6 (G to G)
Frequency: 60Hz
Lamp Type: 6 strings WLED Without Driver
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V