Technical description and composition of the TELEFUNKEN TF-LED39S35T2 TV, panel type and applicable modules. The composition of the modules.TELEFUNKEN LED
Model: TF-LED39S35T2
Chassis / Version: MSD3463-T8C1
Panel: K390WD5 K390WD5UB280H200
LED backlight: 44 LED * 3V
T-CON: T390XVN01.0 CTRL BD; AUO-11311, P301-16, M106-11, AUO-G1422, 4G32
LED driver (backlight): integrated into MainBoard
PWM LED driver: MP3394S
MOSFET LED driver: AOD256
Power Supply (PSU): integrated into MainBoard
PWM Power: OB5269CP
MOSFET Power: AOTF10N65
MainBoard: MSD3463-T8C1
IC MainBoard: MX25L6406E TPA3110D2
Control: IR: 4707-48L51F-A52A4F01; Service Mode: MENU 8202
Technical Specifications TF-LED39S35T2
TELEFUNKEN TF-LED39S35T2
General repair guidelines for TV LCD LED
Possible malfunctions
- TELEFUNKEN TF-LED39S35T2 TV does not turn on at all. There is no reaction to the remote control or to the control buttons from the front panel. Indicator lights do not light or flash.
First of all, in such cases, you should verify the operability of the common switching power supply (IIP) - AC / DC voltage converter of the mains voltage. All source elements in this TV model are located on the MainBoard MSD3463-T8C1 main board. Then we recommend that you measure its output voltages and, if they are absent, you should check the health of the power switches (AOTF10N65) and rectifier diodes of the converters for possible short circuit.
During thermal or avalanche breakdowns of semiconductors in the secondary circuits of any converter, as a rule, it can operate in emergency short circuit mode without output voltages, and during short circuit in the elements of the primary circuit, the main fuse and, less often, the current sensor at the source of the key are most often cut off.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can put it out of operation in key mode or provoke the excess of maximum current or voltage values. It can be supply, damper circuits, or elements of OOS (negative feedback) stabilization. The reason for the breakdown of the power key may be PWM (PWM) OB5269CP. It is checked only by replacement with a known good one.
- There is no image, there is sound, it responds to the remote control. Or the image may appear for a second when turned on and immediately disappears.
As a rule, in such cases there is no display backlight. 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 TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the motherboard MSD3463-T8C1 should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). If it is not possible to replace the MB board (SSB), you need to check the health of its elements - MX25L6406E TPA3110D2. Defective components should be replaced.
I recommend the owners of the TF-LED39S35T2 TV for repair only to qualified specialists with the necessary work experience! Self-repair attempts without the appropriate knowledge and skills can lead to irreversible negative consequences!
FIRMWARE SPI FLASH ----------------> TELEFUNKEN TF-LED39S35T2 , Main: MSD3463-T8C1, Panel: K390WD5 K390WD5UB280H200
Service mode: MENU 8202
TELEFUNKEN TF-LED39S35T2
Service mode: MENU 8202
On the panel 44 LED 3 volts.
You can reduce the current by changing the rating of two resistors connected between the case and the 6 pins of the MP3394S.
11k + 16k = 6.5k current = 283ma.
11k + 24k = 7.5k current = 240ma.
11k + 36k = current 8.4k = 219ma.
11k + 43k = 8.7k current = 208ma.
Current 11k = 167ma.
TV LED IC MP3394/MPS3394S LED Driver Diagnostics Throubleshooting
The earlier MP3394 was replaced by MPS3394S, which is an upgraded version of the same IC, and found in the 17IPS20 power supply board. It is the main heart of the backlighting LED drive and the failure of this IC can cause the TV not to start. This is a voltage step-up IC that takes 5-V to 28-V at its input pin 15 (Vin) and raises it to drive four independent strings of LEDs. It also performs other functions such as voltage regulation between the LED strings, and provides a dimming facility using pulse-width modulation (PWM). An important aspect of this IC is that it has built-in open and short LED protection circuitry. It is also able to sense the current and voltage of the LED matrix load and determine abnormal conditions. That means that if all the LEDs in the matrix go open or short, it will prevent the television from switching ON.
The IC has internal control logic that produces the GATE signal to drive an external MOSFET transistor. This is the transistor that is switched against an inductor to step-up the voltage, and the gate signal is produced only when the internal control logic detects normal conditions. It is able to determine normal/abnormal conditions through internal comparators, and one such is the LED Over-Voltage Protection (LED OVP) comparator that provides Short String Protection (SSP).
When the TV is switched ON, this IC is enabled through pin 2, by a voltage greater than 1.8-V. It first checks the circuit configuration, and then checks the over-voltage protection signal at (pin 12) to determine if the rectifier diode is open and whether the booster MOSFET (driven by the GATE signal) is short to ground. If the OVP voltage at pin 12 is lower than 70-mV (may be different for other board versions), then it disables itself and the TV will not start.
On the 17IPS20 board, the GATE signal is known as GATE_LED, which drives a bi-polar junction transistor (BJT) Q500 (BC858B). This transistor then drives Q502/Q503 MOSFET booster group of transistors to step-up the voltage (shown in the following pages of this article). In this circuit configuration the inductance coils are L500 and L501. The high voltage produced then goes into a group of rectifier diodes D503 and D504 producing a positive DC voltage for the LEDs. The over voltage protection signal is known as OVP_LED. Whilst all the LED strings take their power from this positive voltage source, they all have separate independent drain pins through the MPS3394S controller IC.
There are also other parameters to consider such as Under-Voltage Lock-Out (UVLO), which is determined by measuring the rising-edge of Vin. This parameter has to be between 3.5-V and 4.4-V, with 3.9-V being the typical value. It is a very clever IC as it can also detect open and short LED strings in the backlight array.
Although this diagnostic cannot tell you the condition of each individual diode, it can indicate the condition of each string of diodes in the backlight matrix. The MPS3394S IC (SOIC16 package) drives four separate strings of LEDs through dedicated open drain output pins. LED string 1 is driven by pin 11, LED string 2 by pin 10, LED string 3 by pin 9, and LED string 4 by pin 8. It also monitors the voltages at these pins so that if there was a shorted LED in one of the strings then it would disconnect that string. If the voltage at any of these pins is greater than 6.1-V, then this condition triggers the short circuit protection mechanism for disconnecting the string at that pin. It is also possible to determine an open string, and in this case, this condition is detected when the pin voltage is lower than 196-mV.
Interestingly, this IC is designed such that it will always try to light at least one string if it is working. The only time when the step-up converter shuts-down completely is if all the strings were either open, or short. Therefore, before you rush off to eBay to buy a new chip, measure the voltages at these pins to make sure that the diodes are not faulty. Otherwise, you will end up wasting a lot of time and money!
To reduce the backlight current in the LED drivers with the MP3394S controller (MP3394), increase the resistance of the pin 6 resistance (ISET) to the chassis. The maximum current in each channel (in milliamps) for the resistance Rset (in kilo-ohms) is determined from the ratio 790 * 1.23 V / (Rset + 0.4).Main board repair
The appearance of the MainBoard MSD3463-T8C1 is illustrated in the figure below:
MSD3463-T8C1
The MSD3463-T8C1 can be used in televisions:
PHILIPS 32PHT4001 / 60 (panel K320WD92), PHILIPS 43PFT4001 / 60 (panel K430WD9), TELEFUNKEN TF-LED39S35T2 (Panel K390WD5 K390WD5UB280H200), TELEFUNKEN TF-LED32S35T2 (Panel K390W35)
Main characteristics of the TELEFUNKEN TF-LED39S35T2 device:
Installed matrix (LED panel) K390WD5 K390WD5UB280H200.
The matrix control uses the synchronization controller (T-CON) T390XVN01.0.
To supply the backlight LEDs, a converter is used, associated with the main board MSD3463-T8C1, controlled by the MP3394S PWM controller. Keys of type AOD256 are used as power supplies for the LED driver.
The power module is combined with the MainBoard and is manufactured in accordance with the AC / DC Flyback voltage conversion circuit using OB5269CP chips and AOTF10N65 type power switches.
MainBoard - the motherboard (motherboard) is an MSD3463-T8C1 module, using the MX25L6406E TPA3110D2 and other chips.