Technical description and composition of the LG 26LB75-ZE TV, panel type and applicable modules. The composition of the modules.LG
Model: 26LB75-ZE
Chassis / Version: LD73C
Panel: V260B1-L03 Rev. C3
Inverter (backlight): VTT70038.50 REV: 3
PWM Inverter: OZ964SN KIA78M05F AS324M E1
MOSFET Inverter: BA712U, BA7128
Power Supply (PSU): EAX31845101 EAY3303030
PWM Power: ICE3B0365J (Standby), FA5501A (PFC), U3037M, LAF0001, MIC4428YM
MOSFET Power: W20NM60, P9NK60Z, 62T03GH
MainBoard: EAX37632202 (0)
IC MainBoard: FLi8548H-LF, 24LC256, 29LV320CTTC-70G, HY825DC256160CE-5, CXA2069Q, MSP4450K E8, STi5100GUC
Tuner: TDFC-G107P
Control: MKJ40653802
Specifications 26LB75
LG 26LB75-ZE
General recommendations for repairing TV LCD
It is advisable to start repairing an LG TV with the LD73C chassis with a careful external inspection of both internal and external elements. It often happens that visible damage to elements or connections helps determine the direction of the troubleshooting. In some cases, faulty elements can be seen with the naked eye, for example, charred resistors or swollen metal-ceramic capacitors, or electrolytic in rectifier filters. Ring cracks formed in the soldered terminals of transformers or heating elements of the circuit are also frequent sources of many malfunctions with a variety of external manifestations.
In the absence of any signs of operability, when the LG 26LB75-ZE does not turn on and does not signal anything with the control lights on the panel, there is a possibility of a malfunction of the TV's EAY3303030 power module. With the same manifestations, the power regulator of the control processor on the motherboard may be faulty. 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 the transistors W20NM60, P9NK60Z, 62T03GH and rectifier bridge diodes should be checked for avalanche (thermal) breakdown.
It should be remembered that in the practice of repair, usually the power switches in switching power supplies (SMPS) do not fail due to their poor quality and, in such cases, it is necessary to look for the cause that led to a malfunction and provoked a breakdown of the key. Most often, the culprits of the accident are dried electrolytic capacitors or dangling resistors in the primary circuit, or the ICE3B0365J, 5501A, U3037M, LAF0001, MIC4428YM PWM chip itself may be faulty. It is also necessary to check all the semiconductor elements of the stabilization circuit in the primary and secondary circuits.
In cases where the LG 26LB75-ZE TV has lost an image, and the sound is there and all other functions are operational, there is a possibility of an inverter (converter for powering the backlight) malfunction. 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 the inverter protection (to enable diagnostics), special care must be taken in view of the risk of failure of power elements. After completing all repair work, it is imperative to restore the protection circuits for full and safe further operation of the TV by the user.
Diagnosis and repair of the EAX37632202 (0) 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. In some cases, it is necessary to check or replace (if necessary) the elements of the MB board (SSB) - FLi8548H-LF, 24LC256, 29LV320CTTC-70G, HY825DC256160CE-5, CXA2069Q, MSP4450K E8, STi5100GUC, Tuner - TDFC-G107P. In cases where the BGA processor is used, its malfunction is usually detected by local heating.
Owners of 26LB75-ZE TVs are recommended to contact qualified specialists with experience for repairs! Self-repair attempts without the appropriate knowledge and skills can lead to serious negative consequences!
SCHEMATIC MANUAL -------------------------> LG 26LB75, 26LB75-ZE, 26LB76, 26LB76-ZF Chassis LD73C.
The appearance of the MainBoard EAX37632202 is shown in the figure below:EAX37632202
EAX37632202 can be used in TVs:
LG 26LB75-ZE (Panel V260B1-L03 Rev. C3), LG 32LB76-ZD (Panel LC320WX6 (SL)(A3)), LG 32LB75 (Panel LC320WXN (SA)(A1)).
PSU Advanced
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 5501A PWM boost converter. 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 26LB75-ZE:
Installed matrix (LCD panel) V260B1-L03 Rev. C3
The VTT70038.50 inverter is used to power the backlight, controlled by the OZ964SN KIA78M05F AS324M E1 PWM controller. As power elements of the inverter, keys of the type BA712U, BA7128 are used.
The necessary supply voltages for all nodes of the LG 26LB75-ZE TV are generated by the EAX31845101 power module or its analogs using ICE3B0365J (Standby), FA5501A (PFC), U3037M, LAF0001, MIC4428YM microchips and power switches of the type W20NM60, P9NK60Z, 62T03H.
MainBoard - the main board (motherboard) is an EAX37632202 module, using chips FLi8548H-LF, 24LC256, 29LV320CTTC-70G, HY825DC256160CE-5, CXA2069Q, MSP4450K E8, STi5100GUC and others.
The TDFC-G107P tuner provides TV reception and channel tuning.
Information from an alternative source:
LG 26LB75-ZE chassis LD73C MATRIX: V260B1-L03 Rev. C3 (China)
Motherboard:EAX37632202 (0), IC700 - FLi8548H-LF, IC701 - 24LC256, IC703 - 24C04WP, IC201, IC802 - 29LV320CTTC-70G, IC202, IC801 - HY825DC256160CE-5, IC103 - 24LC256, IC1400 - CXA2069Q, IC1301 - STA3350W, IC1302 - MSP4450K E8, IC100 - STi5100GUC, IC410 - LCX157F828, Tuner - TDFC-G107P
Inverter: VIT70038.50 REV: 3, U5 - OZ964SN, U1 - KIA78M05F, U3 - AS324M E1, Q8, Q9 - BA712U, Q10, Q11 - BA7128
PSU: - EAY3303030, U500 - ICE3B0365J, U600 - 5501A, U201 - U3037M, U100 - LAF0001, U101 - MIC4428YM, Q606 - W20NM60, Q150, Q151 - P9NK60Z, Q205, Q207 - 62T03GH
Remote control: - MKJ40653802 TV scheme, ENTERING THE SERVICE MENU: simultaneously press and hold the OK buttons on the remote control and the TV.
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
