Technical description and composition of the SAMSUNG UE55NU7100U TV, panel type and modules used. The composition of the modules.
SAMSUNG LED
Model: UE55NU7100U
Chassis / Version: KANT-M2E
Panel: CY-NN055HGLV2V
LED backlight: EDGE LED 55NU
LED driver (backlight): integrated into PSU
PWM LED driver: SLM4283A SOP-20 StepDown
MOSFET LED driver: N-FET TO-220F
Power Supply (PSU): BN44-00932B L55E6_NSM
PWM Power: PFC, PWM
MOSFET Power: N-FET TO-220F
MainBoard: BN41-02635B BN94-13275E
IC MainBoard: CPU, eMMC: KLM4G1FEPD, SPI 25Q40, EEPROM: 24C512, DRAM, AUDIO: TAS5749M
Tuner: BN40-00331A
UE55NU7100U Specifications
SAMSUNG UE55NU7100U
General recommendations for TV LCD LED repair
Possible manifestations of malfunctions
- SAMSUNG UE55NU7100U TV does not turn on at all. No response to the remote control and front panel control buttons. Indicator lamps do not light up or flash.
Most likely in this case, the main switching power supply (SMPS) BN44-00932B is faulty. It is necessary to measure its output voltages, and in case of their absence (full or partial), the serviceability of the power switches (N-FET TO-220F) of the converters and rectifier diodes should be checked for a possible short circuit.
In case of any breakdowns in the secondary circuits, the converter can operate in an emergency mode of a short circuit, and with a short circuit in the power elements of the primary circuit, the mains fuse or the current sensor at the source of the key is often cut off.
Breakdown of power switches (MosFet) in switching sources is sometimes caused by malfunctions of other circuit elements, for example, in the circuits supplying the PWM controller, frequency setting or damper, as well as in the circuits of Negative Feedback (OOS) stabilization. PWM controllers (PWM) PFC, PWM, if they do not have visible damage to the case and an outright short circuit between the pins, are usually checked by replacement.
- No picture, sound, all other TV functions are working. When turned on, the image may sometimes appear for a second.
The backlight of the matrix (LED panel) is usually faulty in these cases. The reason may be found in the malfunction of the LEDs, in the violation of the contact connections of the EDGE LED 55NU LED strips, or in the provision of their power supply (LED driver).
It is impossible to check the line of series-connected LEDs without a special current source, and it is unsafe for them to use any voltage sources above 12V for this purpose. Then all that remains is to open the panel and check each LED separately. Usually, Chinese multimeters with 9V power supply lightly light up one 3-volt LED, if you connect the probes to it in the forward direction, the red probe to the anode, and the black one to the cathode. For dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of the LED health. In the event of a malfunction of the LED, its zener diode will either be cut off or pierced in the K / Z.
If SAMSUNG UE55NU7100U has no picture, but there is sound, often the display backlight CY-NN055HGLV2V simply does not work. Moreover, in LED TVs, the LEDs inside the panel usually fail, less often the LED driver.
In such cases, you can see a barely noticeable image with a successful hit of external light on the screen.
Replacing the LEDs requires disassembling the LCD panel CY-NN055HGLV2V - a process that requires experience and qualifications from the master. We do not recommend doing such work on your own to the owners of TVs and craftsmen who do not have experience in repairing LCD panels
If there is no image, and the backlight is on, the screen becomes slightly lighter when turned on, and in an open TV you can see light through the holes in the panel case.
In this case, the panel may also be faulty - damage to strips, loops, for example, as a result of moisture ingress after unsuccessful washing of the screen, the T-CON (Timing Controller) board may be faulty. But often the main board MainBoard BN41-02635B turns out to be faulty, a software failure is also possible.
Then, first of all, you need to check the panel supply voltage, fuses on the T-CON board, as well as the supply and reference voltages of the column and line drivers - VGH, VGL, Vcom.
If these measurements are within normal limits, it is necessary with an oscilloscope to track the passage of LVDS signals from the MainBoard BN41-02635B, as well as synchronization signals to the loops with drivers.
Flooded or unsuccessfully washed screens of LED-TVs can be restored, in about half of the cases, usually if significant damage has not formed in the loops and panel strips.
- 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 BN41-02635B 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). In some cases, to repair the MB (SSB) board, it may be necessary to replace chips - CPU, eMMC: KLM4G1FEPD, SPI 25Q40, EEPROM: 24C512, DRAM, AUDIO: TAS5749M with new or known good ones. In cases where BGA technologies are used, defects are usually localized by heating.
If the TV operates normally from external devices, but does not tune to TV channels, the BN40-00331A tuner may be faulty. In such cases, first of all, you should make sure that there are supply voltages at its corresponding terminals. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus. Sometimes the reason for the inoperability of the tuner may be a software failure.
Once again, we remind TV users: do not try to repair yourself without the appropriate knowledge, experience and the necessary qualifications! Trust the repairs to professionals with sufficient experience in the field of electronic repair.
Additional MainBoard Repair
The appearance of the MainBoard BN41-02635B is shown in the figure below:
BN41-02635B
External view of the power supply
Main features of the SAMSUNG UE55NU7100U device:
The matrix (LED-panel) CY-NN055HGLV2V is installed.
A converter combined with a power supply is used to power the backlight LEDs, and is controlled by the SLM4283A SOP-20 StepDown PWM controller. N-FET TO-220F switches are used as power elements of the LED driver.
The formation of the necessary supply voltages for all nodes of the SAMSUNG UE55NU7100U TV is carried out by the BN44-00932B power module, or its analogs using PFC, PWM microcircuits and N-FET TO-220F power switches.
MainBoard - the main board (motherboard) is a BN41-02635B module, using CPU chips, eMMC: KLM4G1FEPD, SPI 25Q40, EEPROM: 24C512, DRAM, AUDIO: TAS5749M and others.
The BN40-00331A tuner provides reception of television programs and tuning to channels.
Instructions and updates
There are files to download for the UE55NU7100U model from the manufacturer:
Latest firmware updates (latest firmwares):
File type File name Version Date Size
Update instruction 2018_TV_Firmware_Upgrade_Instruction_T-KTM2LDEUC.pdf 1.0 23.06.2020 0.5 Mb
Update file (USB) T-KTM2LDEUC.zip 1310.4 02.11.2020 1117.74 Mb
Update file (USB) T-KTM2LDEUC_1310.4.exe 1310.4 02.11.2020 1117.49 Mb
Update file (USB) T-KTM2LDEUC_1310.4_RU.exe 1310.4 02.11.2020 1117.49 Mb
User Manuals and Instructions:
File type File name Version Date Size
User manual BN68-08987G-02_UNU7100X_EN_L02_180710.1.pdf 02 13.07.2018 1.22 Mb
Brief instructions BN68-08995L-01_QSG_UNU7100X_CIS_180314.0.pdf 01 23.05.2018 0.3 Mb
Instruction PDF ENG_KM2DVBEUN-3.0.2_181205.0.pdf 3.0.2 02.01.2019 11.33 Mb
Instruction PDF RUS_KM2DVBEUN-3.0.2_181205.0.pdf 3.0.2 02.01.2019 11.42 Mb
Files can be downloaded from the manufacturer's website for the UE55NU7100 model.
SAMSUNG UE55NU7100U TV with LCD CY-NN055HGLV2V, diagonal 54.6 "(139 cm) in 16: 9 format. This model uses a panel with edge LED backlighting - Edge LED.
CY-NN055HGLV2V sensor and MainBoard BN41-02635B software are capable of realizing images in the highest UHD quality at 3840x2160 resolution in 4K UHD, HDR standard. Image processing is performed using modern High Dynamic Range (HDR) technology with an extended range of brightness gradations.
TV model UE55NU7100U has built-in software (software) SMART and installed Tizen Operating System. The connection to the network can be carried out via Wi-Fi wireless connection. Supported media file formats: MP3, WMA, MPEG4, HEVC (H.265), DivX, MKV, JPEG.
Speaker sound system power 20 W (2x10 W) is provided by two speakers. The NICAM stereo audio processing system and the Sound Surround function are used.
Communication with other devices via an external interface is supported by standard input and output connectors: antenna input (RF), AV, component, HDMI x3, USB x2, Ethernet (RJ-45), Wi-Fi 802.11ac, Miracast. The digital tuner is capable of receiving television channels in the DVB-T, DVB-T2, DVB-C, DVB-S, DVB-S2 standards.
The power consumed when operating from the network is 150 W. BN44-00932B power supply.
Dimensions: with stand 1239x793x261 mm, without stand 1239x714x59 mm.
TV weight: with stand: 17.7 kg, without stand: 17.3 kg.
Attention! Panel CY-NN055HGLV2V LED TV SAMSUNG UE55NU7100U is an expensive and unreliable element.
Do not allow any impact 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 unrepairable.
