Technical description and composition of the LG 26LC41-ZA TV, panel type and applicable modules. The composition of the modules.LG
Model: 26LC41-ZA
Chassis / Version: LP78A
Panel: V260B1-L03 Rev. C3
Inverter (backlight): VIT70038.50
PWM Inverter: OZ964SN
MOSFET Inverter: AO D413, AO D454
Power Supply (PSU): EAX31845101 EAY3302510 LGLP2627HEP
PWM Power: ICE3B0365J (Standby), LAF001 (FAN7601 PWM 8pin), FA5501 (PFC)
MOSFET Power: W20NM60, P9NK60Z, 62T03GH
MainBoard: EAX32572503 (1) 73EBR36475002002
IC MainBoard: ANX9021 VCT6993P TEA6420 TPA3107D2 OZ964SN AS324M-E1 CM1671A PS65161
Tuner: TAFT-W005D
Control: MKJ39170805
Specifications 26LC41
LG 26LC41-ZA
General recommendations for repairing TV LCD
It is recommended that you start troubleshooting diagnostics and repairing LGs with the LP78A chassis, as well as other electronic devices, with an external inspection of the external and internal elements. In some cases, visible external damage to the elements can indicate the direction of troubleshooting and localization of the defect even before the start of the necessary measurements at the control points of electronic circuit nodes. 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 TV does not turn on, no indicators on its front panel are lit or blinking. Also, if the TV does not respond to the remote control and buttons, does not make any sounds or any signs of operability when turned on, there is a certain chance that the EAY3302510 EAX31845101 LGLP2627HEP power supply module is defective and needs repair. Sometimes with similar manifestations a problem can only occur in the absence of processor power, which is typical for certain LG models. When diagnosing and repairing the power supply, after replacing the swollen capacitors of the secondary rectifier filters (if any), you must first check the mains fuse. When it is broken, the power elements of transistors and rectifier bridge diodes should be checked for avalanche (thermal) breakdown.
As a rule, the keys in switching power supplies (SMPS) are reliable enough and rarely fail for no reason to be looked for by checking other components of the circuit - electrolytic capacitors, resistors and semiconductor elements of the primary circuit. The PWM chip is verified by replacing it with a known good one.
In cases where the LG 26LC41-ZA TV has lost its image, and the sound is there and all the other functions are operational, 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. When disabling protection for diagnostic purposes, it must be remembered that in this case there is a risk of failure of the power elements of the inverter. Upon completion of the diagnosis, all regular protection circuits should be restored.
Diagnosis and repair of the LP78A EAX32572503 (1) 73EBR36475002002 motherboard is carried out by checking the performance of the stabilizers or power converters of the module chips. In some cases, a software update is required. If it is not possible to replace the MB (SSB) card, you need to check the health of its elements - ANX9021, VCT6993P, TEA642,0 TPA3107D2, OZ964SN, AS324M-E, 1 CM1671A, PS65161, tuner TAFT-W005D. Defective components should be replaced.
Remember! Attempts to self-repair by users of the LG 26LC41-ZA TV without the appropriate qualifications and necessary experience can lead to serious negative consequences!
SCHEMATIC MANUAL ----------------> LG 26LC41/4R, 26LC41/4R-ZA, 26LC42, 26LC42-ZC Chassis LP78A.
According to the conditions of compliance with modern world standards for household switching power supplies, the EAX31845101 module provides for the use of a Power Factor Correction unit. The PFC circuit is a flyback converter based on the FA5501 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 26LC41-ZA:
Installed matrix (LCD panel) V260B1-L03 Rev. C3.
The VIT70038.50 inverter is used to power the backlight lamps, it is controlled by the OZ964SN PWM controller. As power elements of the inverter, keys of the type AO D413, AO D454 are used.
The necessary supply voltages for all nodes of the LG 26LC41-ZA TV are generated by the EAX31845101 power module or its analogs using ICE3B0365J (Standby), LAF001 (FAN7601 PWM 8pin), FA5501 (PFC) microcircuits and power switches of the type W20NM60, P9NK60Z, 62T03GH.
MainBoard - the main board (motherboard) is an EAX32572503 module, using ANX9021 VCT6993P TEA6420 TPA3107D2 OZ964SN AS324M-E1 CM1671A PS65161 chips and others.
The TAFT-W005D tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: CMO
Model: V260B1-L03
Type: a-Si TFT-LCD, Panel
Diagonal size: 26.0 inch
Resolution: 1366x768, WXGA
Display Mode: TN, Normally White, Transmissive
Active Area: 575.769x323.712 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 800: 1
Display Colors: 16.2M (6-bit + FRC), CIE1931 72%
Response Time: 3/5 (Tr / Td)
Frequency: 60Hz
Lamp Type: 12 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 12.0V