Sunday 9 August 2020

REPAIRING / SERVICING TV SKYLINE 32U5010

Technical description and composition of the SKYLINE 32U5010 TV, panel type and modules used. The composition of the modules.
SKYLINE LED
Model: 32U5010
Chassis / Version: RR52CI.812A
Panel: HV320FHB-N02
T-CON: HV320FHB-N02 47-6021088
LED driver (backlight): integrated into MainBoard
PWM LED driver: SO-8
MOSFET LED driver: TO-252
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MOSFET Power: TO-252
MainBoard: RR52CI.812A
IC MainBoard: SPI Flash: MX25L6405D
Tuner: NoName
Specifications 32U5010
SKYLINE 32U5010
General recommendations for TV LCD LED repair
Possible malfunctions
- SKYLINE 32U5010 TV does not turn on at all. Control lamps do not light up or blink. The TV on the remote control and control panel buttons does not respond.
In this case, the main power supply, the AC / DC voltage converter, may be faulty, the elements of which in this model are located on the main board MainBoard RR52CI.812A. Then you should measure its output voltages and, in case of their complete or partial absence, it is necessary to check the serviceability of the power switches (TO-252) and the rectifier diodes of the converters for a possible short circuit.
In case of breakdowns in the secondary circuits, the converter, as a rule, can operate in an emergency in the short-circuit mode, and in the event of a short circuit in the power elements of the primary circuit, the mains fuse is usually cut off.
Breakdown of Mos-Fet switches used in switching power supplies is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM regulator, in frequency-setting or damper circuits, as well as in negative feedback stabilization. PWM microcircuits (PWM) PWM SOT23-6 are usually checked by replacing them with new ones, or knowingly working.
- There is no picture, there is sound, it reacts to the remote control, the channels are switched. In some cases, the image appears when turned on and disappears immediately.
A malfunction is usually in these cases most likely in the backlight units of the display matrix. The reason can sometimes be in the power supply of the LEDs, but more often in their malfunction (breakdown or open circuit), sometimes in the violation of the contact connections of the LED strips.
It should be remembered that it is not possible to determine an open circuit in the LED lines without disassembling the panels using 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 you need 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 LEds are used, then the PN transition of the emergency zener diode can indirectly serve as an indicator of serviceability. In the event of a malfunction of the LED-a, the PN-transition of the Zener diode will either be cut off or broken into the K / Z.
- The TV does not turn on, the indicator signals standby or operating mode, or blinks.
Repair or diagnostics of the RR52CI.812A motherboard should begin with checking the stabilizers and power converters required to power the microcircuits and matrix. If necessary, you should update or replace the software (software). If it is not possible to replace the MB (SSB) board, it is necessary to check the serviceability of its elements - SPI Flash: MX25L6405D. Defective components must be replaced.
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 NoName tuner and update the software. I2C communication pulses must be monitored with an oscilloscope.
Owners of the 32U5010 TV are advised to contact only qualified specialists with the necessary experience for repair! Attempts to repair yourself without the appropriate knowledge and skills can lead to irreversible negative consequences!
Additional MainBoard Repair
The appearance of the MainBoard RR52CI.812A is shown in the figure below:
RR52CI.812A
The main features of the SKYLINE 32U5010 device:
The matrix (LED panel) HV320FHB-N02 is installed.
Matrix control uses the HV320FHB-N02 Timing Controller (T-CON).
To power the backlight LEDs, a converter combined with the RR52CI.812A main board is used, controlled by the SO-8 PWM controller. TO-252 switches are used as power elements of the LED driver.
The power module is combined with the MainBoard and is made according to the AC / DC flyback voltage converter using PWM SOT23-6 microcircuits and TO-252 power switches.
MainBoard - the main board (motherboard) is an RR52CI.812A module, using SPI Flash chips: MX25L6405D and others.
Tuner NoName provides reception of television programs and tuning to channels.