Technical description and composition of the TELEFUNKEN TF-LED28S18 TV, panel type and modules used. The composition of the modules.TELEFUNKEN LED
Model: TF-LED28S18
Chassis / Version: MS82MT
Panel: TH280-L03
LED backlight: TC280-F1004-YTJ-LA2
T-CON: ST3151A05-4-XC-3
LED driver (backlight): integrated into PSU
PWM LED driver: OB3362RP
Power Supply (PSU): 40-ES2820-PWE1XG
MainBoard: 40-MS82MT-MAB2HG
IC MainBoard: MST6M300ST, 24C32
Tuner: NoName
TF-LED28S18 Specifications
TELEFUNKEN TF-LED28S18
General recommendations for TV LCD LED repair
Possible manifestations of malfunctions
- TELEFUNKEN TF-LED28S18 TV does not turn on. There are no signs of operability. The indicators on the front panel do not light up or blink, the TV does not respond to the remote control and control buttons.
With similar manifestations, in some cases, the 40-ES2820-PWE1XG power supply module is faulty. Then we recommend measuring its output voltages and, if they are absent, you should check the serviceability of the power switches and rectifier diodes of the converters for a possible short circuit.
In case of breakdowns of semiconductors in the secondary circuits of any converter, as a rule, it can operate in an emergency mode of short circuit without output voltages, and with a short circuit in the elements of the primary circuit, the mains fuse most often breaks off immediately and, less often, the current sensor in the source of the key.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can disable it in the key mode, or provoke an excess of the maximum current or voltage values. These can be circuits supplying the PWM controller, damper or frequency setting circuits, or OOS (negative feedback) elements in the stabilization circuit. PWM controllers (PWM), in the absence of external damage and a short circuit between the terminals, are checked by replacing them with a known good one.
- 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.
Usually, in such cases, a malfunction is detected in the nodes of the backlight of the LED panel. The reason may be both in the power supply of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
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 needed to open PN junctions connected in series.
- The indicator on the front panel blinks, the TV does not turn on in operating mode, does not respond to the remote control.
Repair or diagnostics of the 40-MS82MT-MAB2HG 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). Repair of the board and replacement of microcircuits MST6M300ST, 24C32 are performed if the necessary equipment and the corresponding element base are available. Malfunctions associated with the use of BGA soldering technologies can be localized by warming up.
Before replacing the NoName tuner, if there is no tuning to the channels, you must first check the software and the supply voltage at its outputs. You also need to make sure that the tuner and processor can exchange data via the I2C bus
Once again, we remind TV users: do not attempt to repair yourself without the appropriate knowledge, experience and the necessary qualifications! Trust the repair to professionals with sufficient experience in the field of electronic repair.
DOWNLOAD FIRMWARE FOR SPI FLASH -----------> TELEFUNKEN TF-LED28S18, Main: 40-MS82MT-MAB2HG, Panel: TH280-L03
To reduce the backlight current in LED drivers with OB3362RP (TSOP16) controller, increase the total resistance of the resistors from pin 5 (ISET) to the case. The maximum current in each of the four channels (in milliamperes) for the Rset resistor (in kilo-ohms) is determined from the ratio 3000 * 1.2V / Rset.
Additional MainBoard RepairThe appearance of the MainBoard 40-MS82MT-MAB2HG is shown in the figure below:
40-MS82MT-MAB2HG
External view of the power supply
Main features of the TELEFUNKEN TF-LED28S18 device:
Installed matrix (LED panel) TH280-L03.
Matrix control uses the ST3151A05-4-XC-3 Timing Controller (T-CON).
A converter combined with a power supply is used to power the backlight LEDs, and is controlled by the OB3362RP PWM controller.
The formation of the necessary supply voltages for all nodes of the TELEFUNKEN TF-LED28S18 TV is carried out by the 40-ES2820-PWE1XG power module, or its analogs.
MainBoard - the main board (motherboard) is a 40-MS82MT-MAB2HG module, using MST6M300ST, 24C32 and others.
Tuner NoName provides reception of television programs and tuning to channels.
TELEFUNKEN TF-LED28S18 TV with LCD TH280-L03, 28 "(71 cm) 16: 9. Brightness of the screen of 300 cd / m² is provided by LED backlighting. Contrast, as the ratio of maximum brightness to minimum, is 3000 : 1. The LED panel of this TV is equipped with Edge LED, which can display high quality HD images at a resolution of 1366x768 pixels in 720p (HD Ready). , SECAM, NTSC Graphic processing and digital signal shaping takes place in 480i, 480p, 576i, 576p, 720p standards Supported multimedia file formats: MP3, WMA, MPEG4, Xvid, DivX, MKV, JPEG.
Speaker power of 10 W (2x5 W) is provided by two speakers. The NICAM STEREO audio processing system is used.
External interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, audio x2, component, VGA, HDMI, USB. To connect a computer or laptop to this TV model, use the VGA (D-Sub 15) connector on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768, 1360x768.
Overall dimensions: 657x454x140 mm.
TV weight: 5 kg.
Attention! The panel TH280-L03 of the TELEFUNKEN TF-LED28S18 LED TV is an expensive and unreliable element.
Do not allow any impacts 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 non-repairable.