Technical description and composition of the LG 22LN457U TV, panel type and modules used. The composition of the modules.
LG LED
Model: 22LN457U
Chassis / Version: LD31T
Panel: LC216EXN (SF) (A1)
LED backlight: 6916L-1237A 21.6 V13 EDGE REV0.1 2 6920L-0001C
T-CON: 6870S-1619B LC216EXN_SFA1_Source_Ver 0.7 H / F; TL2345ML, TPS65170
LED driver (backlight): integrated into T-CON
PWM LED driver: BD9472EFV SOP24
MOSFET LED driver: RSD050N10
Power Supply (PSU): Adapter 19V 2.1A
MainBoard: EAX65077504 (1.0)
IC MainBoard: CPU: LGE2121-MS, SPI Flash: MX25L8005, DRAM: H5TQ1G63EFR, Audio: TNP7513
Tuner: TDSQ-G601D (B)
Specifications 22LN457U
LG 22LN457U
General recommendations for TV LCD LED repair
Possible malfunctions
- The LG 22LN457U TV does not turn on, does not respond to the remote control and control panel buttons, does not light or blink indicators.
Most often, with similar manifestations, the main adapter power module turns out to be faulty.
The power source in this model is an external Adapter 19V 2.1A, usually the owners of TVs can purchase them on their own, and their repair may be impractical. But sometimes it is not difficult to open the unit and eliminate simple typical defects characteristic of most SMPS. It is necessary to measure its secondary output voltages, and if they are absent, check the power switches and rectifier diodes in the converters for a short circuit.
In case of diode breakdowns in the secondary circuits, the converter can operate in an emergency mode of short circuit without output voltages, and with a short circuit in the power elements of the primary circuit, the mains fuse and / or the current sensor in the source of the key usually breaks off.
Mos-Fet power switches used in switching power supplies sometimes fail due to a malfunction of any other elements that can disable it in the key mode, or create an excess of the maximum permissible key parameters. These can be elements supplying a PWM regulator, frequency setting or damper circuits, or elements of negative feedback in the stabilization circuit. PWM controllers, in the absence of visible damage or outright short circuits between the terminals, are checked by replacing them with new ones, or knowingly working properly.
- There is no image, there is sound, it reacts to the remote control. Or, immediately after switching on for a second, the image may appear and immediately disappear.
In such cases, the most likely malfunction of the LED panel backlighting elements. Most often the reason for this is a break in the LEDs, or poor contact in the connectors of the brackets, less often the LED driver may be faulty.
When trying to detect a break in the LED lines, it should be borne in mind that it is difficult to do this without disassembling the panel. For example, a current source is required to open PN junctions connected in series.
If the LG 22LN457U has no picture, but there is sound, often the LCD backlight LC216EXN (SF) (A1) simply does not work. Moreover, in LED TVs, the LEDs inside the panel usually fail, less often the LED driver.
In such cases, you can see a barely noticeable image with a successful hit of external light on the screen.
Replacing the LEDs requires disassembling the LC216EXN LCD panel, a process that requires experience and qualifications from the technician. We do not recommend doing such work on your own to the owners of TVs and craftsmen who do not have experience in repairing LCD panels
If there is no image, and the backlight is on, the screen becomes slightly lighter when turned on, and in an open TV, light is visible through the holes in the panel case.
In this case, the panel may also be faulty - damage to strips, loops, for example, as a result of moisture ingress after unsuccessful washing of the screen, the T-CON (Timing Controller) board may be faulty. But the main board MainBoard EAX65077504 (1.0) often turns out to be faulty, a software failure is also possible.
Then, first of all, you need to check the panel supply voltage, the fuses on the T-CON board, as well as the supply and reference voltages of the column and line drivers - VGH, VGL, Vcom.
If these measurements are within normal limits, it is necessary to trace the passage of LVDS signals from MainBoard EAX65077504 (1.0) with an oscilloscope, as well as synchronizing signals to loops with drivers.
Flooded or unsuccessfully washed screens of LED TVs can be restored, in about half of the cases, usually if significant damage has not formed in the loops and panel strips.
- The indicator blinks or is on constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the EAX65077504 motherboard should begin with checking the stabilizers and power converters required to power the microcircuits and matrix. If necessary, you should update or replace the software (software). In some cases, to repair the MB (SSB) board, it may be necessary to replace the chips - CPU: LGE2121-MS, SPI Flash: MX25L8005, DRAM: H5TQ1G63EFR, Audio: TNP7513 with new or known good ones. In cases where BGA technologies are used, defects are usually localized by heating.
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 supply voltage of the TDSQ-G601D tuner (B) and update the software. I2C communication pulses must be monitored with an oscilloscope.
Remember! Attempts to self-repair the LG 22LN457U TV, in the absence of the necessary qualifications and experience, are categorically not recommended and are fraught with negative consequences, up to the complete non-repairability of the device!
DOWNLOAD FIRMWARE FOR SPI FLASH -----------> 22LN457U
Driver current limitation. BD9472EFV LC216EXN_SFA1.
General recommendations
To reduce the backlight current in LED drivers with a BD9472EFV controller on the T-CON board, you can increase the total resistance of the resistors from pin 23 (ISET) of the BD9472EFV to the case. The exact proportional relationship may not be observed, the values should be selected empirically.
BD9472EFV LED-Driver, T-CON 6870S-1619B LC216EXN_SFA1:
In LED drivers with a BD9472EFV chip on the T-CON bar, you can increase the total resistance of the resistors from pin 23 (ISET) of the BD9472EFV to the case. The exact proportional relationship may not be observed, the values should be selected empirically.
The drawing was compiled by hand visually from the T-CON bar, there was no documentation for the BD9472EFV on the Internet.
For the LC216EXN (SF) (A1) panel and 6916L-1237A backlight bar, the current was initially 70 mA in each of the two channels at maximum (a few seconds after switching on without a signal).
After increasing one of the resistors from 91 kOhm to 160 kOhm, the current decreased to 50 mA.
Diodes of standard size 7020, double, but the transitions are connected in parallel inside, therefore - three-volt.
There are 28 LEDs on the bar - two channels of 14 each.
Additional MainBoard Repair
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 LG 22LN457U device:
Installed matrix (LED panel) LC216EXN (SF) (A1).
Matrix control uses the 6870S-1619B Timing Controller (T-CON).
An integrated LED driver is used to power the backlight LEDs, controlled by the BD9472EFV SOP24 PWM controller. RSD050N10 keys are used as power elements of the LED driver.
An external adapter 19V 2.1A is used to power all the internal components of the LG 22LN457U TV.
MainBoard - the main board (motherboard) is an EAX65077504 module using CPU chips: LGE2121-MS, SPI Flash: MX25L8005, DRAM: H5TQ1G63EFR, Audio: TNP7513 and others.
Tuner TDSQ-G601D (B) provides reception of TV programs and tuning 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
Instructions and updates
There are files to download for model 22LN457U from the manufacturer:
Files with updates and instructions:
File Description File Name Type Date Size
SW File (Version 03.10.13). Firmware (USB) Software_File (Version_03.10.13) .zip ZIP 30.11.2016 62777K
SW File (Version 03.10.13). Update instruction TV_Software_Update_Guide_v3.pdf PDF 30.11.2016 1938K
Compatible with 22LN450U-ZB, 22LN457U-ZI, 26LN450B-ZB, 26LN450U-ZB, 26LN457B-ZI, 26LN457U-ZI, 28LN450U-ZB, 28LN457U-ZI, 29LN450B-Z50N-29LN445
Software Upgrade Guide. Upgrade instructions Software_Upgrade_Guide (CIS) .pdf PDF 08/20/2013 743K
User Manuals and Instructions:
File type File name Language Date Size
User manual MFL67707907_ (1404) _04REV.pdf English, Russian 08/14/2014 56,952K
Quick Start Guide NC4_L_E_L05_140306_ENG.pdf English 03/07/2014 8,750K
The files can be downloaded from the manufacturer's website for the 22LN457U model.
LG 22LN457U TV with LCD display LC216EXN (SF) (A1), 22 "(56 cm) diagonal, 16: 9 format. This model uses a panel with edge LED backlighting - Edge LED.
The LC216EXN sensor and MainBoard EAX65077504 (1.0) software provide high quality HD viewing at a resolution of 1366x768 pixels in 720p (HD Ready). The input analog video signal is decoded in PAL, SECAM, NTSC systems. Graphic processing of a digital signal is performed in the 480i, 480p, 576i, 576p, 720p, 1080i, 1080p standards. Supported media file formats: MP3, MPEG4, Xvid, DivX, JPEG.
The power of the acoustic system of sound is 10 W (2x5 W), provided by two speakers. The NICAM stereo audio processing system and the Sound Surround function are used.
Communication with other devices via an external interface is supported by standard input and output connectors: antenna input (RF), AV, component, SCART, RGB, VGA, HDMI, MHL, USB. A headphone jack is provided. A VGA (D-Sub 15) connector is provided to connect a computer or laptop to this TV model. This interface supports standard resolutions: 640x480, 800x600, 1024x768, 1280x1024, 1360x768. The digital tuner is capable of receiving television channels in the DVB-T, DVB-T2, DVB-C, DVB-S, DVB-S2 standards.
The power consumed when operating from the mains is 30 W. External power supply Adapter 24V.
Dimensions: With stand 513x362x140 mm, Without stand 513x320x63 mm.
Attention! Panel LC216EXN LED-TV LG 22LN457U is an expensive and unreliable element.
Do not allow any impact on the glass and pressure on the screen surface to avoid damage to the LED panel!
It is also unsafe for liquid to spill onto the screen. Sometimes one drop is enough if it drips down the glass onto the cables to make the TV unrepairable.
