Technical description and composition of the LG 32LH595U TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 32LH595U
Chassis / Version: LD66K / LD66Y
Panel: HC320DXN-ABVS2-5112
LED driver (backlight): integrated into MainBoard
PWM LED driver: MP3378E
Power Supply (PSU): LCAP45 19V 2.5A
MainBoard: EAX66853404 (1.1) - LD66K-LD66Y
IC MainBoard: EEPROM: 24C256
Tuner: TDJM-G301D EBL61741401
Specifications 32LH595U
LG 32LH595U
General repair guidelines for TV LCD LED
In the case when the 32LH595U 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 LCAP45 19V 2.5A power supply module is probably faulty in this case. 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 rectifier bridge of the mains voltage and the power key (s) of the converter. The complete inoperability of the power supply unit can be caused by a short circuit in the power elements in the primary circuit, followed by an open fuse, or a short circuit in the loads.
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 PWM controller 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.
If the LG 32LH595U does not have an image, there is sound and the channels are switched, there is a possibility of a malfunction in the backlight LED circuit of the HC320DXN-ABVS2-5112 panel, or their power converter is an LED driver. Sometimes, when turned on, the image appears and immediately disappears. In such cases, it is necessary to check the electrolytic capacitors of the power filter of the backlight unit.
To check the health of the LEDs, as well as contact connections in the ruler circuit, it is necessary to disassemble the panel.
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 test 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
On the motherboard EAX66853404 (1.1) - LD66K-LD66Y, in case of a malfunction, you should first check the performance of all the stabilizers and power converters of the microcircuits, and also, if necessary, update the software (software).
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 EBL61741401. 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.
Attention! For users and owners of 32LH595U TVs who do not have the appropriate qualifications, knowledge and experience, we categorically do not recommend attempting self-repair in order to avoid negative consequences that could lead to complete non-serviceability of the device.To reduce the backlight current in LED drivers with the MP3378E PWM controller, it is necessary to proportionally increase the total resistance of the resistors from pin 3 (RISET) to the chassis. Calculation of current in milliamperes and resistance in kilo-ohms 977 / Rset for each channel. Parallel channels are summed. For example, for four parallel channels and a RISET 10 KOhm resistance, the total current will be 97.7 * 4 = 391 mA.
More details on this page
The appearance of the MainBoard EAX66853404 is shown in the figure below:EAX66853404
EAX66853404 can be used in TVs:
LG 32LH595U (Panel HC320DXN-ABVS2-5112), LG 32LH570U (Panel HC320DXN-VHVS1-214X).
Main features of the device LG 32LH595U:
Installed matrix (LED-panel) HC320DXN-ABVS2-5112.
To power the backlight LEDs, a converter is used, combined with the main board EAX66853404, controlled by the MP3378E PWM controller.
The formation of the necessary supply voltages for all nodes of the LG 32LH595U TV is carried out by the LCAP45 power supply module, or its analogs.
MainBoard - the main board (motherboard) is an EAX66853404 module, using EEPROM chips: 24C256 and others.
The TDJM-G301D EBL61741401 tuner provides TV reception and channel tuning.
