Technical description and composition of the LG 40LF634V TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 40LF634V
Chassis / Version: LD51H / LE51H
Panel: V400HJ6-PE2 Rev. C1 HC400DUN-VCKN1-214X
LED backlight: DRT4.0 REV0 7 B-Type SVL400
T-CON: CM2801C, CM805, CM603
LED driver (backlight): integrated into PSU
PWM LED driver: LC5901
Power Supply (PSU): EAX66163001 (1.8) P / N: EAY63630401
PWM Power: MAP8800, SSC3S901
MOSFET Power: MMP60R360P 11A 600V
MainBoard: EAX66207203 (1.0)
IC MainBoard: AT24C256, H26M31001HPR (e-NAND), K4B4G1646D-BCK0, K4B2G1646Q-BCK0, TPS65175B, NTP7515D
Tuner: TDJM-G301D
Specifications 40LF634V
LG 40LF634V
General repair guidelines for TV LCD LED
Possible manifestations of defects
- LG 40LF634V does not turn on, the indicators on the front panel do not light or flash. The TV does not respond to the control buttons and the remote control.
With such manifestations, in some cases, the EAX66163001 power module turns out to be faulty. It is necessary to measure its output voltages, and in case of their absence (full or partial), it is necessary to check the serviceability of the power switches of the converters and rectifier diodes for the presence of a possible short circuit.
In case of breakdowns of semiconductors in the secondary circuits, the converter can usually work abnormally in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse often breaks.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damping circuits, as well as in Negative Stabilization Feedback. PWM chips MAP8800, SSC3S901 are usually checked by replacing with new ones, or obviously working.
- There is no image, but there is sound and reaction to commands from the remote control. Or the image appears immediately after turning on and disappears.
In such cases, the most likely malfunction of the LED backlight elements. 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.
It is impossible to check the line of series-connected LEDs without a special current source, and for this purpose it is not safe to use any voltage sources above 12V. Then it remains only to open the panel and check each LED separately. Usually, Chinese 9V-powered multimeters light up a single 3-volt LED, if you connect the probes in the forward direction, the red probe to the anode, and the black to the cathode. In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as a health indicator. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the EAX66207203 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). In some cases, to repair the MB board (SSB), it may be necessary to replace the chips - AT24C256, H26M31001HPR (e-NAND), K4B4G1646D-BCK0, K4B2G1646Q-BCK0, TPS65175B, NTP7515D with new or obviously working ones. In cases where BGA technologies are used, defects are usually localized by the heating method.
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 tuner TDJM-G301D. 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.
Once again, remind users! Attempts to self-repair the LG 40LF634V TV without the appropriate qualifications and the necessary experience can lead to its complete unrepairability!
LED current in the panel = 220mA. To reduce the current DRT4.0 REV0 7, you can increase the value of the resistor EAX66163001 R816 3 ohm current = 220mA, 3.9ohm current = 173mA.
Schematic diagram ------------> LG 40LF634V Chassis LD/LE51H. CHASSIS : LB51H; MODEL : 40LF63**, 40LF63**-T*
FIRMWARE EEPROM 24C256 ------------> LG 40LF634V LD51H/LE51H, Main: EAX66207203(1.0), Panel: V400HJ6-PE2 Rev.C1 HC400DUN-VCKN1-214X
The appearance of the MainBoard EAX66207203 (1.0) is shown in the figure below:EAX66207203 (1.0)
The appearance of the power supply
Main features of the device LG 40LF634V:
Installed matrix (LED-panel) V400HJ6-PE2 Rev. C1 HC400DUN-VCKN1-214X.
The matrix control uses the Timing Controller (T-CON) CM2801C.
To power the backlight LEDs, a converter is used, combined with the power supply, controlled by the LC5901 PWM controller.
The necessary supply voltages for all nodes of the LG 40LF634V TV are generated by the EAX66163001 power module or its analogs using MAP8800, SSC3S901 microcircuits and power switches of the MMP60R360P 11A 600V type.
MainBoard - the main board (motherboard) is an EAX66207203 (1.0) module, using AT24C256, H26M31001HPR (e-NAND), K4B4G1646D-BCK0, K4B2G1646Q-BCK0, TPS65175B, NTP7515D and others.
The TDJM-G301D tuner provides TV reception and channel tuning.