Technical description and composition of the LG 32LE7500 TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 32LE7500
Chassis / Version: LD03D
Panel: LC320EUH (SC) (A4)
T-CON: LGE7378A
LED driver (backlight): 3PHAC40003A-R (integrated into PSU)
PWM LED driver: AS3693B, MEGA48PA
Power Supply (PSU): PLDC-L901A EAY60802801
PWM Power: FAN6961 (PFC), L6599D (PWM Resonant), VIPer27L (STB)
MOSFET Power: SD14N60, 04N60C3
MainBoard: EAX61762608 (1)
IC MainBoard: CPU: LGE3556C, Micom: UPD78F0513A, Audio: NTP7000, NAND: TC58NVG2S3, DDR: NT5TU128M8DE, HDMI: TDA19997
Tuner: TDFR-G155D
Specifications 32LE7500
LG 32LE7500
General repair guidelines for TV LCD LED
Possible malfunctions
- The LG 32LE7500 TV does not turn on, does not respond to the remote control and the control panel buttons, the indicators do not light up and do not blink.
Often in such cases, the PLDC-L901A power 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 any breakdown of semiconductors in the secondary circuits, the converter can usually work normally in emergency short circuit mode. There are no output voltages. And with a short circuit in the power elements of the primary circuit, as a rule, the mains fuse breaks and less often the current sensor at the source of the key.
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 microcircuits are usually checked by replacement 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 some of these cases, the malfunction is caused by a lack of backlighting on the display. The reason can be both in the power of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
When diagnosing, it is necessary to take into account that it is impossible to check the open in the chain of LED lines without disassembling the panels using a tester or multimeter. To open all PN junctions connected in series, a voltage of the order of several tens of volts is required, and ideally, a current source. By opening the panel, each LED can be checked separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect probes in the forward direction to it. 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 indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the EAX61762608 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). Sometimes it is necessary to check or replace (if necessary) the elements of the MainBoard board - CPU: LGE3556C, Micom: UPD78F0513A, Audio: NTP7000, NAND: TC58NVG2S3, DDR: NT5TU128M8DE, HDMI: TDA19997. In cases where the BGA processor is used, its malfunction is usually detected by the local heating method.
If the TV works normally from external devices, but does not tune into television channels, the TDFR-G155D tuner may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding conclusions. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus. Sometimes the cause of the inoperability of the tuner may be a software failure.
Attention! For users and owners of 32LE7500 TVs who do not have the appropriate qualifications, knowledge and experience, we strongly recommend against attempting self-repair in order to avoid negative consequences that could lead to complete non-repairability of the device.
Service manual and schematic diagram LG 32LE7500 Chassis LD03D.
LG 32LE7500, 32LE750N , 32LE7500-ZA, 32LE750N-ZA, 32LE7800, 32LE77900 , 32LE7800-ZA, 32LE7900-ZA, 32LE7510, 32LE77910, 32LE7510-ZB, 32LE7910-ZB
The appearance of the MainBoard EAX61762608 is shown in the figure below:EAX61762608
EAX61762608 can be used in TVs:
LG 32LE5500 (Panel LC320EUH (SC)(A1)), LG 37LE5500 (Panel LC370EUH), LG 32LE7500 (Panel LC320EUH (SC)(A4)).
The appearance of the power supply
Main features of the device LG 32LE7500:
Installed matrix (LED-panel) LC320EUH (SC) (A4).
The matrix control uses the Timing Controller (T-CON) LGE7378A.
To power the backlight LEDs, a converter is used, combined with a power supply unit, controlled by a PWM controller AS3693B, MEGA48PA.
The necessary supply voltages for all nodes of the LG 32LE7500 TV are generated by the PLDC-L901A power module, or its analogs using FAN6961 (PFC), L6599D (PWM Resonant), VIPer27L (STB) microcircuits and power switches of the type SD14N60, 04N60C3.
MainBoard - the main board (motherboard) is an EAX61762608 module, using CPU chips: LGE3556C, Micom: UPD78F0513A, Audio: NTP7000, NAND: TC58NVG2S3, DDR: NT5TU128M8DE, HDMI: TDA19997 and others.
The TDFR-G155D tuner provides television reception and channel tuning.
Additional technical information about the panel:
Brand: LG Display
Model: LC320EUH-SCA4
Type: a-Si TFT-LCD, Panel
Diagonal size: 31.5 inch
Resolution: 1920x1080, FHD
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 698.4x392.85 mm
Frequency: 120Hz
Lamp Type: WLED
