Technical description and composition of the SAMSUNG UE43NU7090U TV, panel type and applicable modules. The composition of the modules.SAMSUNG LED
Model: UE43NU7090U
Chassis / Version: KANT-SU
Panel: CY-NN043HGEVDH
LED driver (backlight): integrated into MainBoard
PWM LED driver: SOP-16
MOSFET LED driver: TO-252 N-FET
Power Supply (PSU): integrated into MainBoard
PWM Power: PFC & PWM 16 pin
MOSFET Power: N-FET TO-252
MainBoard: NU7090 KANT-SU
IC MainBoard: CPU, DC / DC, eMMC, DRAM, AUDIO
Tuner: BN40-00330B
Technical Specifications UE43NU7090U
SAMSUNG UE43NU7090U
General repair guidelines for TV LCD LED
Possible malfunctions
- The SAMSUNG UE43NU7090U TV does not turn on and does not show any signs of turning on, it does not respond to the control buttons or the remote control.
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 NU7090 main board. Then it is necessary to measure its output voltage and, in case of their complete or partial absence, it is necessary to check the serviceability of power switches (TO-252) and rectifier diodes of the converters for the presence of a possible short circuit.
In case of breakdowns in the secondary circuits, the converter, as a rule, can emergency work in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse usually breaks.
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 an excess of the maximum current or voltage. These can be circuits supplying the PWM controller, damping or frequency-setting circuits, or elements of OOS (negative feedback) in the stabilization circuit. PWM controllers (PWM) PFC & PWM 16 pin, in the absence of external damage and short circuit between the terminals, are checked by replacing with obviously good ones.
- There is no image, the screen is black, there is sound, with external illumination of the screen, you can sometimes see barely noticeable outlines of the image.
Usually in such cases, a malfunction is detected in the backlight nodes of the LED panel. The reason can be found in the failure of the LEDs, in the violation of the contact connections of the LED strips, or in the provision of their power (LED-driver).
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 indicator on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the NU7090 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).
If there is no reception of television channels, but the TV is working properly from external devices, first of all, check the voltage of the tuner BN40-00330B and update the software. The pulses from the I2C bus must be controlled with an oscilloscope.
Attention TV owners! Attempts to self-repair SAMSUNG UE43NU7090U are not recommended by the manufacturer and can lead to serious negative consequences!
The appearance of the MainBoard NU7090 is shown in the figure below:Main features of the SAMSUNG UE43NU7090U device:
Installed matrix (LED panel) CY-NN043HGEVDH.
To power the backlight LEDs, a converter is used, combined with the NU7090 main board, controlled by the SOP-16 PWM controller. As power elements of the LED driver, keys of the TO-252 N-FET type are used.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using PFC & PWM 16 pin microcircuits and N-FET TO-252 type power switches.
MainBoard - the main board (motherboard) is a NU7090 module, using CPU, DC / DC, eMMC, DRAM, AUDIO, and others.
The tuner BN40-00330B provides the reception of television programs and tuning to channels.