Technical description and composition of the LG 22LN548M TV, panel type and applicable modules. The composition of the modules.LG LED
Model: 22LN548M
Panel: LC216EXN (SF) (A1)
LED driver (backlight): LC216EXN_SFA1
PWM LED driver: DT1641AS (TPS40210)
MOSFET LED driver: AOD478
Power Supply (PSU): Adapter
MainBoard: EAX65077504 (1.0)
IC MainBoard: LGE2121-MS A7M4987ZC, MX25L8006E, TNP7513, H5TQ2G63DFR, H5TQ1G63EFR
Tuner: TDSQ-G601D (B)
Technical Specifications 22LN548M
LG 22LN548M
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The LG 22LN548M TV does not turn on and does not show any signs of operability at all. There is no reaction to the remote control and control buttons from the front panel.
In such cases, the adapter power supply is usually faulty.
This TV model is equipped with an external adapter type power supply, which the owner can purchase independently, and repairing it may not always be advisable, however, sometimes it makes sense to open it and eliminate simple typical defects typical of IPS. It is necessary to measure its output voltages, and in case of their absence, check the operability of the power switches of the converters and rectifier diodes for the probability of a short circuit.
In case of breakdowns in the secondary circuits, the converter can operate in a short circuit mode, and during short circuit in the elements of the primary circuit, the mains fuse usually breaks.
Mos-Fet power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. PWM controllers, in the absence of visible damage or frank short-circuit between the terminals, are checked by replacing with new, or obviously working.
- There is no image, there is sound, it is responding to the remote control. Or immediately after turning on for a second, the image may appear and immediately disappear.
In some of these cases, the malfunction is caused by a lack of backlighting on the display. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
It should be remembered that it is not possible to determine the open circuit in the LED lines without disassembling the panels with a tester or multimeter without an additional device, for example, a current source. To open all PN junctions connected in series at once, a voltage of several tens of volts may be required. Then it is necessary to open the panel and check each LED separately with a multimeter. If the capabilities of your multimeter do not allow you to open the LED in the forward direction or dual LEd are used, then the PN junction of the emergency zener diode can indirectly serve as a health indicator. In case of LED-a failure, the zener diode PN junction 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 EAX65077504 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). In cases of attempts to repair the MB board (SSB), it is necessary to check the health of its elements - LGE2121-MS A7M4987ZC, MX25L8006E, TNP7513, H5TQ2G63DFR, H5TQ1G63EFR which may require replacement with new ones. If a BGA processor is installed, there is a possibility of a violation of the soldering of the contacts of its conclusions with the board (it is diagnosed by heating).
In cases where there is no 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 TDSQ-G601D (B) tuner. 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.
It should be remembered! Attempts to self-repair the LG 22LN548M 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!
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 22LN548M:
Installed matrix (LED panel) LC216EXN (SF) (A1).
The LED driver LC216EXN_SFA1 is used to power the backlight LEDs, it is controlled by the PWM controller DT1641AS (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 22LN548M TV, an external adapter 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