Technical description and composition of the LG 22LN450U TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 22LN450U 22LN457U
Chassis / Version: LD31T
Panel: LC216EXN (SF) (A1)
T-CON: LC216EXN SFA1 Ver 0.7
LED driver (backlight): integrated into MainBoard
PWM LED driver: DT1641AS (TPS40210)
MOSFET LED driver: AOD478
Power Supply (PSU): Adapter 24V
MainBoard: EAX65077504 (1.0)
IC MainBoard: LGE2121-MS A7M4987ZC, MX25L8006E, TNP7513, H5TQ2G63DFR, H5TQ1G63EFR
Tuner: TDSQ-G601D (B)
Technical Specifications 22LN450U
LG 22LN450U
General repair guidelines for TV LCD LED
Malfunctions of the Adapter 24V power supply module can be expressed in different ways, for example, LG 22LN450U does not turn on at all and the control lamps on its front panel do not light up and do not blink, there are no signs of operability. After checking the mains fuse and power elements of the primary power supply circuit, it should also check the absence of a short circuit in the loads of the secondary rectifiers.
If a breakdown of the power switch is detected, it should be remembered that in a switching power supply (IIP) it does not fail by itself without any reasons that should be sought by checking other elements of the primary circuit - electrolytic capacitors, PWM PWM controller, which can be checked only by replacement, as well as other semiconductor elements (diodes, transistors, zener diodes).
If the LG 22LN450U has no image, there is sound and the channels are switched, there is a possibility of a malfunction in the backlight LED circuit of the LC216EXN (SF) (A1) panel, or their power converter - 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.
The lack of backlight often occurs due to an open circuit in the LED circuit. There is a need for disassembling the panel and checking the LEDs themselves, as well as the same contact connections in the connectors and rations of the terminals.
It is impossible to detect a break in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and to open their transitions, a voltage of several tens of volts is required. Ideally, a current source is suitable for such purposes. You can open the panel and check each LED separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect the probes in the forward direction to it (red probe to the anode, black to the cathode). In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of health. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
In cases of attempts to repair the motherboard EAX65077504 (1.0), it is necessary to check the operability of the linear stabilizers and power converters of its microcircuits and, if possible, update the software (software). BGA chips can sometimes be diagnosed with local heating.
In cases of complex repairs of MB (SSB) and in the presence of the necessary skills and equipment, sometimes it may be necessary to replace its chips LGE2121-MS A7M4987ZC, MX25L8006E, TNP7513, H5TQ2G63DFR, H5TQ1G63EFR and other possible faulty components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
If there is no reception of television channels, but the TV is working properly from external devices, first of all you need to check the voltage of the tuner TDSQ-G601D (B) and update the software. The pulses from the I2C bus must be controlled with an oscilloscope.
Attention to the owners! Attempts to repair the LG 22LN450U TV independently are not recommended by the manufacturer and can lead to serious negative consequences!
Service manual and schematic diagram -----------> LG 22LN450U, 22LN457U, CHASSIS: LC31A / LD31T, MODEL: 22LN45** 22LN45**-Z*
LG 22LN457U - White body color. Main: EAX65077504(1.0); PANEL:LC216EXN(SF)(A1);
CPU: LGE2121-MS, SPI FLASH: MX25L8005, DRAM: H5TQ1G63EFR;
TUNER: TDSQ-G601D(B).
FIRMWARE FOR SPI FLASH -------------------> LG 22LN450U, 22LN457U
To reduce the backlight current in LED drivers with a DT1641AS controller (DT1641S), you can increase the total resistance of the resistors from pin 7 (RISET) to the chassis. The exact proportional dependence may not be observed if there is additional control on this input, then the ratings should be selected empirically.
More details on this page
The appearance of the MainBoard EAX65077504 is shown in the figure below:EAX65077504
EAX65077504 can be used in TVs:
LG 24MN33V PZ (Panel V236BJ1-LE1 Rev. C2), LG 22LN450U 22LN457U (Panel LC216EXN (SF) (A1)), LG 22LN548M (Panel LC216EXN (SF) (A1)).
Main features of the device LG 22LN450U:
Installed matrix (LED panel) LC216EXN (SF) (A1).
The matrix control uses the Timing Controller (T-CON) LC216EXN.
To power the backlight LEDs, a converter is used, combined with the EAX65077504 main board, controlled by the DT1641AS PWM controller (TPS40210). As the power elements of the LED driver, keys of the AOD478 type are used.
To power all the internal components of the LG 22LN450U TV, an external adapter 24V type source is used.
MainBoard - the main board (motherboard) is an EAX65077504 module, using chips LGE2121-MS A7M4987ZC, MX25L8006E, TNP7513, H5TQ2G63DFR, H5TQ1G63EFR and others.
The TDSQ-G601D (B) tuner allows you to receive television programs and tune to channels.
Additional technical information about the panel:
Brand: LG Display
Model: LC216EXN-SFA1
Type: a-Si TFT-LCD, Panel
Diagonal size: 21.6 inch
Resolution: 1366x768, WXGA
Display Mode: IPS, Normally Black, Transmissive
Active Area: 477.417x268.416 mm
Surface: Antiglare (Haze 1%), Hard coating (3H)
Brightness: 250 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (8-bit), 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