Technical description and composition of the TELEFUNKEN TF-LED40S28T2 TV, panel type and modules used. The composition of the modules.TELEFUNKEN LED
Model: TF-LED40S28T2
Chassis / Version: CV9202H
Panel: CX400DLEDM
LED driver (backlight): integrated into PSU
PWM LED driver: BIT3260
MOSFET LED driver: AOB254
Power Supply (PSU): CVB42001
PWM Power: LD7535 (PWM SOT23-6)
MOSFET Power: SMK1060
MainBoard: CV9202H-TPW
IC MainBoard: SPI FLASH: 25Q64BV
Tuner: ST03WS-2A-E
TF-LED40S28T2 Specifications
TELEFUNKEN TF-LED40S28T2
General recommendations for TV LCD LED repair
Possible manifestations of defects
- The TELEFUNKEN TF-LED40S28T2 TV does not turn on and does not show any signs of turning on. There is no reaction to the control buttons and to the remote control.
In such cases, the fault should be looked for first of all in the CVB42001 power supply module. It is necessary to measure its secondary output voltages, and in their absence, check the serviceability of the power switches of the converters and rectifier diodes for a possible 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 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 supply, damper circuits, or elements of OOS (negative feedback) stabilization. The reason for the breakdown of the power switch can also be PWM. It is checked only by replacing it with a known good one.
- There is no picture, but there is sound and reaction to the remote control. Or the image may appear for a second immediately after switching on.
The malfunction in most of these cases is found in the nodes and elements of the LED panel backlighting. 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 blinks or is on constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the CV9202H-TPW motherboard should begin with checking the stabilizers and power converters necessary to power the microcircuits and matrix. If necessary, you should update or replace the software (software). Complex repair of MB (SSB) is possible only in a service center with the necessary equipment. Checking or replacing SPI FLASH: 25Q64BV elements requires the necessary training and professional skills to repair modules at the component level. Problems associated with the use of BGA soldering technologies can sometimes be diagnosed by the warm-up method.
If there is no reception of TV channels, but the TV is working properly from external devices, first of all, you need to check the supply voltage of the ST03WS-2A-E tuner and update the software. I2C communication pulses must be monitored with an oscilloscope.
We remind users again! Attempts to repair the TELEFUNKEN TF-LED40S28T2 TV without proper qualifications and the necessary experience can lead to its complete non-repairability!
Additional MainBoard Repair
The MainBoard CV9202H-TPW is shown in the figure below:
CV9202H-TPW
CV9202H-TPW can be used in TVs:
AKAI LEA-39J29P (Panel HF390BGA-C1), BBK 32LEM-1001/T2C (Panel CX315DLEDM), DNS M39DM8 (Panel V390HJ1-P02 Rev C1), ERISSON 32LEE17 (Panel 720p HD 1366x768), FUSION FLTV-32T22 (Panel ST3151A05), FUSION FLTV-28T20 (Panel LCM-SM275TK301 (D0306)), FUSION FLTV-28T22 (Panel TH280L321-04), FUSION FLTV-32T23 (Panel ST3151A04-1 / Ver.2.4), FUSION FLTV-32T20 (Panel V320BK1-PS5 Rev.C7), TELEFUNKEN TF-LED40S28T2 (Panel CX400DLEDM), TELEFUNKEN TF-LED29S30T2 (Panel V290BJ1-XC01 CX290DLEDM), TELEFUNKEN TF-LED40S6T2 (Panel CX400DLEDM).
External view of the power supply
Main features of the TELEFUNKEN TF-LED40S28T2 device:
Installed matrix (LED panel) CX400DLEDM.
A converter combined with a power supply is used to power the backlight LEDs, and is controlled by a BIT3260 PWM controller. The keys of the AOB254 type are used as power elements of the LED driver.
The formation of the necessary supply voltages for all nodes of the TELEFUNKEN TF-LED40S28T2 TV is carried out by the CVB42001 power module, or its analogs using LD7535 microcircuits (PWM SOT23-6) and power switches of the SMK1060 type.
MainBoard - the main board (motherboard) is a CV9202H-TPW module, using SPI FLASH chips: 25Q64BV and others.
The ST03WS-2A-E tuner provides reception of television programs and tuning to channels.
TELEFUNKEN TF-LED40S28T2 TV with LCD CX400DLEDM, diagonal 40 "(102 cm) in 16: 9 format. The brightness of the screen is 280 cd / m² provided by LED backlighting. Contrast, as the ratio of maximum brightness to minimum brightness, is 3500: 1 The LED panel of this TV is equipped with Edge LED backlighting.The design and technical capabilities of the TV provide viewing of broadcasts and movies in high quality HD at a resolution of 1920x1080 pixels in graphic resolution according to the standard 1080p (Full HD) .Input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal shaping occurs in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, WMA, MPEG4, Xvid, DivX, MKV , JPEG.
Speaker power of 16 W (2x8 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, VGA, HDMI x3, USB. A headphone output is provided. 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, 1280x1024, 1360x768, 1920x1080.
The digital tuner is capable of receiving TV channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Overall dimensions: 910x571x210 mm.
TV weight: 9 kg.
Attention! Panel CX400DLEDM LED TV TELEFUNKEN TF-LED40S28T2 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.