Monday 30 December 2019

REPAIR / SERVICING TV SAMSUNG T28E310EX

Technical description and composition of the SAMSUNG T28E310EX TV, panel type and applicable modules. The composition of the modules.
SAMSUNG LED
Model: T28E310EX
Panel: HJ028AGH-R1
LED backlight: D4GE-280DC0-R2 BN41-02168A
LED driver (backlight): integrated into PSU; 63V 350mA
Power Supply (PSU): BN44-00695A
PWM Power: S3330 (FAN6755)
MOSFET Power: MMF60R580P
MainBoard: BN41-02105A
IC MainBoard: CPU: NT14L, Spi Flash W25Q40BL, Eeprom AT24C256, Audio: NTP7414
Tuner: BN40-00287A
Technical Specifications T28E310EX
SAMSUNG T28E310EX
General repair guidelines for TV LCD LED
Possible malfunctions
- SAMSUNG T28E310EX TV does not turn on, does not respond to the remote control and control panel buttons, indicators do not light up and do not blink.
Often in such cases, the BN44-00695A power module is faulty. It is necessary to measure its secondary output voltages, and if they are absent, check the power switches (MMF60R580P) and rectifier diodes in the converters for 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.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damper circuits, as well as in Negative Stabilization Feedback. PWM chipsets S3330 (FAN6755) are usually checked by replacement with new, or obviously working.
- There is no image, there is sound, there is a reaction to the remote control. Or immediately after turning on for a second, the image may appear and immediately disappear.
A malfunction is usually most likely in these cases at the backlight nodes of the display matrix. The reason can 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.
It is impossible to check the line of series-connected LEDs without a special current source, and for this purpose it is not safe to use any voltage sources above 12V for them. Then it remains only to open the panel and check each LED separately. Usually, Chinese 9V-powered multimeters light up a single 3-volt LED, if you connect the probes in the forward direction, the red probe to the anode, and the black to the cathode. In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as a health indicator. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
- The TV does not turn on, does not respond to the remote control. The indicator blinks or signals standby mode.
Repair or diagnostics of the BN41-02105A motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, you should update or replace the software (software). Board repair and replacement of CPU chips: NT14L, Spi Flash W25Q40BL, Eeprom AT24C256, Audio: NTP7414 are carried out with the necessary equipment, and the corresponding element base. Faults associated with the application of BGA processor soldering technologies can be localized by the heating method.
Before replacing the tuner BN40-00287A, if there is no tuning to the channels, you must first check the software and the supply voltage at its terminals. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus
Attention TV owners! Attempts to self-repair SAMSUNG T28E310EX are not recommended by the manufacturer and can lead to serious negative consequences!


FIRMWARE FOR  SPI FLASH ----->  SAMSUNG T28E310EX , Main: BN41-02105A, Panel: HJ028AGH-R1

 The appearance of the MainBoard BN41-02105A is shown in the figure below:
BN41-02105A
BN41-02105A can be used in TVs:
SAMSUNG T24D310EX (Panel V236BJ1-LE2 REV.C5), SAMSUNG UE28H4000AK (Panel HH028AAGH-R1), SAMSUNG T28D310EX (Panel HH028AGH-R2), SAMSUNG UE22H5000 UE22H5000AK (Panel MG28HT28) UE28J4100AK UE28J4100A (Panel HH028AGH-R2 ST2751A02-1).
The appearance of the power supply
Main features of the SAMSUNG T28E310EX device:
Installed matrix (LED panel) HJ028AGH-R1.
To power the backlight LEDs, a converter is used, combined with a power supply.
The necessary supply voltages for all nodes of the SAMSUNG T28E310EX TV are generated by the BN44-00695A power module or its analogs using S3330 microcircuits (FAN6755) and power switches of the MMF60R580P type.
MainBoard - the main board (motherboard) is a BN41-02105A module, using CPU chips: NT14L, Spi Flash W25Q40BL, Eeprom AT24C256, Audio: NTP7414 and others.
The tuner BN40-00287A provides the reception of television programs and tuning to channels.