Technical description and composition of the LG 32LM3400 TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 32LM3400 32LM3400-ZA
Chassis / Version: LC21B
Panel: LC320DXN (SE) (U2)
T-CON: LC320EXN P / N: 6870C-0370A; TL2345ML, TPS65170, TPS65194, MAX9668E, 404RP
LED driver (backlight): PPW-LE32RG-0 (C) REV0.8
PWM LED driver: BD9285F
MOSFET LED driver: FDD390N15A, 2SC2938
Power Supply (PSU): LGP32F-12P EAX64560501 (1.7) REV 1.1
PWM Power: ICE3BR4765JZ, SC1S311
MainBoard: EAX64317404 (1.0)
IC MainBoard: LGE2111A-T8, H27U1G8F2BTR, W25Q80B, AT24C256C, STA3808WE
Tuner: TDSS-G101D
Specifications 32LM3400
LG 32LM3400
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The LG 32LM3400 TV does not turn on and does not show any signs of turning on; it does not respond to the control buttons or the remote control.
In some of these cases, the main switching power supply, the LGP32F-12P module, is faulty. In the absence of the necessary supply voltages in the secondary circuits of the converters, it is necessary to check the power switches and rectifier diodes for a possible partial or complete breakdown.
In case of breakdowns in the secondary circuits, the converter, as a rule, can emergency work in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse usually breaks.
Mos-Fet power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode, or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. PWM controllers ICE3BR4765JZ, SC1S311, in the absence of visible damage or frank short-circuit between the terminals, are checked by replacing with new ones, or obviously working.
- There is no image, there is sound, it responds to the remote control, the channels are switched. In some cases, the image appears when you turn on and immediately disappears.
In some of these cases, the malfunction is caused by the lack of a backlight display. The reason can be both in the power supply of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
To check the health in the LED circuit, it is better to use a current source with a maximum voltage of 200V. We do not recommend using any voltage sources for this purpose. You can check each LED individually with a simple Chinese multimeter (powered by 9 volts) in the P-N-junction test mode. If you connect the red probe of the multimeter to the anode of the LED, and the black to its cathode, then the 3-volt LED will light up slightly, and in the opposite direction you can detect the transition of the emergency zener diode. A zener diode PN junction indirectly indicates a LED-a
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the EAX64317404 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). When repairing an MB board, you need to check its components LGE2111A-T8, H27U1G8F2BTR, W25Q80B, AT24C256C, STA3808WE. Defective items should be replaced. If chips with BGA soldering technology are used, a problem in its implementation is detected by the local heating of the chip.
In the absence of tuning to the channels of on-air or cable television, you should make sure that the software is correct, as well as in accordance with the ratings of the supply voltage at the terminals of the TDSS-G101D tuner. It is also necessary to check the presence of pulses of data exchange between the tuner and the processor via the I2C bus using an oscilloscope.
For 32LM3400 TV owners, we recommend that you contact qualified personnel with the necessary work experience for repairs! Self-repair attempts without the appropriate knowledge and skills can lead to irreversible negative consequences!
LED current in the panel = 230 mA. If you remove one of the resistors R144-R148 (10th), Current = 170 mA
More details on this page
LG_CHASSIS : LD21C, MODEL: 32LM3400/340S/340T, 32LM3400/340S/340T-ZA SERVICE MANUAL
FIRMWARE SPI FLASH, EEPROM ----------> LG 32LM3400 32LM3400-ZA LC21B, Main: EAX64317404 (1.0) , Panel: LC320DXN (SE)(U2)
The appearance of the MainBoard EAX64317404 is shown in the figure below:EAX64317404
EAX64317404 can be used in TVs:
LG 32LS560T (Panel LC320EUN (SE)(M2)), LG 42LS5600 (Panel T420HVN01.1), LG 47LM580T (Panel LC470EUE (SE)(U1)), LG 42LM3400 (Panel LC420DUN (SE)(U2)), LG 37LS560T (Panel LC370EUN (SE)(M2)), LG 32LM340T (Panel LC320DXN (SE)(U3)), LG 47LM615S (Panel LC470EUE (SE)(U1)), LG 32LM3400 32LM3400-ZA (Panel LC320DXN (SE)(U2)).
The appearance of the power supply
Main features of the device LG 32LM3400:
Installed matrix (LED-panel) LC320DXN (SE) (U2).
The matrix control uses the Timing Controller (T-CON) LC320EXN.
To power the backlight LEDs, the PPW-LE32RG-0 LED driver is used, controlled by the BD9285F PWM controller. As the power elements of the LED driver, keys of the type FDD390N15A, 2SC2938 are used.
The necessary supply voltages for all nodes of the LG 32LM3400 TV are generated by the LGP32F-12P power module, or its analogs using ICE3BR4765JZ, SC1S311 microcircuits.
MainBoard - the main board (motherboard) is an EAX64317404 module, using chips LGE2111A-T8, H27U1G8F2BTR, W25Q80B, AT24C256C, STA3808WE and others.
The TDSS-G101D tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: LG Display
Model: LC320DXN-SEU2
Type: a-Si TFT-LCD, Panel
Diagonal size: 31.5 inch
Resolution: 1366x768, WXGA
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 697.685x392.256 mm
Surface: Antiglare (Haze 1%), Hard coating (2H)
Brightness: 300 cd / m²
Contrast Ratio: 1200: 1
Display Colors: 16.7M (6-bit + Hi-FRC), CIE1931 68%
Response Time: 6 (G to G)
Frequency: 60Hz
Lamp Type: WLED Embedded (LED Driver)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 12.0V