Technical description and composition of the LG M2450D TV, panel type and applicable modules. The composition of the modules.LG LED
Model: M2450D
Chassis / Version: LD02D
Panel: M240HW01
LED driver (backlight): EAX63282604 (REV .0)
PWM LED driver: MAX16814B
Power Supply (PSU): Adapter 19V
MainBoard: EAX62877803 (1)
IC MainBoard: CPU: LGE4369A, DDR: H5PS5162FFA, NAND: HY27US08121B, Sound: NTP7050
Tuner: TDSN-G001D
Technical Specifications M2450D
LG M2450D
General repair guidelines for TV LCD LED
Repair and diagnostics of any electronic device, in particular the LG M2450D, it is advisable to start with a careful external examination of internal and external elements. Often, based on certain external signs, it may be possible to draw certain conclusions about the reasons for the failure of certain elements of the circuit even before the necessary measurements are made, which will determine the further algorithm for troubleshooting and localizing the defect. If charred resistors, swollen electrolytic or cermet capacitors, ring cracks in the solders of the terminals of transformers or heating elements are found, it is advisable to establish the causes and consequences of the malfunction that has arisen, as well as to check the connected elements and assemblies.
If the LG M2450D does not turn on, no control lights on the front panel light up or blink, therefore, there is a very high probability of a malfunction of the Adapter 12V power module. In some cases, only the processor power regulator may be faulty. 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 converter.
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 there is no image when you turn on the LG M2450D, or it appears for a second and disappears, but there is sound, most likely a malfunction in the backlight LED circuit of the M240HW01 panel, or in the power converter. It is necessary to check the electrolytic capacitors of the filter of the secondary rectifiers in the general power supply unit.
In most cases of lack of backlight, it becomes necessary to disassemble the panel in order to check the LEDs, connectors, loops and all contact connections. If one or several LEDs does not work in one line, therefore, they are broken and should be replaced.
When trying to detect a break in the LED lines, it should be taken into account that it is difficult to do this without disassembling the panel. For example, a current source is needed to open PN junctions connected in series.
When trying to repair the motherboard, you should first check the serviceability of linear stabilizers or power converters of microcircuits and, if necessary, update the software (software).
Board repair and replacement of CPU chips: LGE4369A, DDR: H5PS5162FFA, NAND: HY27US08121B, Sound: NTP7050 are carried out with the necessary equipment, and the corresponding element base. Faults associated with the application of BGA processor soldering technologies can be localized by the heating method.
Before changing the TDSN-G001D tuner, if it is not possible to tune to television channels, make sure that there are supply voltages, including varicap power (30-33V), which must be measured at the corresponding tuner pins.
Owners and users of the LG M2450D TV must remember that self-repair without special knowledge, skills and qualifications can be fraught with negative consequences that can lead to complete non-repairability of the device!
Service manual / schematic diagram -------------> LG chassis LD02D; M2450D, M2450D-PZM, M2450D-PCM, M2450D-PRM SERVICE MANUAL
To reduce the backlight current in LED drivers with a PWM controller MAX16814 (TSSOP20 MAX16814B), it is necessary to proportionally increase the total resistance of the resistors from terminal 10 (SETI) to the housing. The maximum current in each of the four channels (in milliamps) for the resistance Rseti (in kilo-ohms) is determined from the ratio 1500 / Rseti.
Main features of the device LG M2450D:Installed matrix (LED-panel) M240HW01.
The EAX63282604 LED driver is used to power the backlight LEDs, it is controlled by the MAX16814B PWM controller.
To power all the internal components of the LG M2450D TV, an external adapter 19V type source is used.
MainBoard - the main board (motherboard) is an EAX62877803 module using CPU chips: LGE4369A, DDR: H5PS5162FFA, NAND: HY27US08121B, Sound: NTP7050 and others.
The TDSN-G001D tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: AUO
Model: M240HW01 V80A
Type: a-Si TFT-LCD, Panel
Diagonal size: 24.0 inch
Resolution: 1920x1080, FHD
Display Mode: TN, Normally White, Transmissive
Active Area: 531.36x298.89 mm
Surface: Antiglare, Hard coating (3H)
Brightness: 350 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (6-bit + Hi-FRC), CIE1931 72%
Response Time: 3.5 / 1.5 (Tr / Td)
Frequency: 120Hz
Lamp Type: 14S4P WLED Without Driver
Signal Interface: LVDS (4 ch, 8-bit), 66 pins
Voltage: 5.0V
