Technical description and composition of the LG 26LC51-ZA TV, panel type and applicable modules. The composition of the modules.LG
Model: 26LC51-ZA
Chassis / Version: LP78A
Panel: V260B1-L03 Rev. C3
T-CON: V260B1-C03, CM1671A-KQ, 324A / 6G97 x2, HX8904TB, P2003EVG, TPS6516
Inverter (backlight): VIT70038.50 REV: 3
PWM Inverter: AS324H-E1, OZ9648N,
MOSFET Inverter: BH6N2N, BA7H1B
Trans Inverter: T51.0104 / 211 B x12
Power Supply (PSU): EAX31845101 Rev1.0
PWM Power: ICE3B0365J (Standby), LAF001 (FAN7601 PWM 8pin), FA5501 (PFC)
MOSFET Power: W20NM60, P9NK60Z, 62T03GH
Mainboard: EBR35843501
IC MainBoard: ANX9021, TPA3107D2, 74ACT253, STMAV340, VCT7993P, HC4066AG, TEA6420, MP2355DN
Tuner: TAFT-W005D
Control: MKJ39170805
Specifications 26LC51
LG 26LC51-ZA
General recommendations for repairing TV LCD
Repair and diagnostics of any electronic device, in particular LG with the LP78A chassis, it is advisable to start with a careful external examination of internal and external elements. Many visible changes in the state of the elements make it possible to determine the future direction of troubleshooting and localizing the defect. Elements with visible damage, for example, capacitors swelled up after boiling the electrolyte, charred resistors in certain nodes of the circuit, as well as ring cracks in solders will help the master to guess the causes and possible consequences of the malfunction.
In the case when the 26LC51-ZA does not turn on, does not respond to the remote control and the front panel buttons, does not blink bulbs and does not show any signs of operability, the EAX31845101 Rev1.0 ICE3B0365J power supply module is probably faulty in this case. If it is serviceable with such manifestations, it is necessary to check the power supply stabilizer (converter) of the processor on the motherboard. When repairing the power supply, it is advisable to start the diagnostics by checking the mains fuse and the electrolytic capacitors of the filters of the converter secondary rectifiers. In the event of a fuse breaking, the reason should be sought in the power semiconductor elements of the pulse converter of the main power supply. First of all, it is necessary to check the diodes of the bridge of the rectifier of the mains voltage and the power switch (s) of the W20NN60 converter.
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.
If the LG 26LC51-ZA TV does not have an image, but there is sound, the malfunction should be sought in the power converter of the backlight (inverter). It is also necessary to check the serviceability of the electrolytic capacitors of the filter of the secondary rectifiers of the BP (power supply) for an overstated ESR. 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.
On the EBR35843501 motherboard, in case of a malfunction, you should first check the operation of all the stabilizers or power converters of the microcircuits and, if necessary, update the software (software). In cases of attempts to repair the MB (SSB) board, it is necessary to check the health of its elements - ANX9021, TPA3107D2, 74ACT253, STMAV340, VCT7993P, HC4066AG, TEA6420, MP2355DN, Tuner: TAFT-W005D, which may require replacement with new ones. If a BGA processor is installed, there is a possibility of a violation of the soldering of the contacts of its conclusions with the board (it is diagnosed by heating).
Owners of 26LC51-ZA TVs are recommended to contact qualified specialists with experience for repair! Self-repair attempts without the appropriate knowledge and skills can lead to serious negative consequences!
SCHEMATIC MANUAL ------------> LG 26LC51(C), 26LC51(C)-ZA, 26LC7R, 26LC7R-ZA 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 26LC51-ZA:
Installed matrix (LCD panel) V260B1-L03 Rev. C3.
The matrix control uses the Timing Controller (T-CON) V260B1-C03.
To power the backlight, an inverter VIT70038.50 is used, controlled by a PWM controller AS324H-E1, OZ9648N,. A transformer T51.0104 / 211 B x12 is installed in the inverter converter. As power elements of the inverter, keys of the type BH6N2N, BA7H1B are used.
The necessary supply voltages for all nodes of the LG 26LC51-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 EBR35843501 module, using ANX9021, TPA3107D2, 74ACT253, STMAV340, VCT7993P, HC4066AG, TEA6420, MP2355DN and other chips.
The TAFT-W005D tuner provides TV reception and channel tuning.
Information from an alternative source:
LG 26LC51-ZA chassis LP78A
Panel Type (Matrix): V260B1-L03 Rev. C3
Motherboard: EAX32572506(0) EBR35843501, ANX9021, TPA3107D2, 74ACT253, STMAV340, VCT7993P, AMTEL7044C32AN, TEA6420, HC4066AG, MP2355DN, 4925B, 24C02BN x3, Tuner: TAFT-W005D
T-con: V260B1-C03, CM1671A-KQ, 324A / 6G97 x2, HX8904TB, P2003EVG, TPS6516
Inverter: VIT70038.50 REV: 3, AS324H-E1, OZ9648N, BH6N2N x2, BA7H1B x2, KIA78M05F, Tr-r: T51.0104 / 211 B x12, IR: EAX35661901 (2)
PSU: EAX31845101 Rev1.0, ICE3B0365J, W20NN60, FAN7601
Remote control: MKJ39170805,
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
