Technical description and composition of the SONY KDL-47W808A TV, panel type and applicable modules. The composition of the modules.SONY LED
Model: KDL-47W808A
Chassis / Version: RB1G
Panel: LC470EUF FF P2
LED driver (backlight): integrated into PSU
PWM LED driver: CXA3854M
MOSFET LED driver: MDF3N50
Power Supply (PSU): APS-342
PWM Power: CXA3810M (PFC & PWM resonant), MIP2H2 (StandBy)
MOSFET Power: KF7N50F, TK15A50D (PFC)
MainBoard: 1-888-101-41 BA2S
IC MainBoard: CPU: CXD4739GB; NAND Flash: TC58DVG3S0ETA00
Technical Specifications KDL-47W808A
SONY KDL-47W808A
General repair guidelines for TV LCD LED
Repair of all electronic devices, including the SONY KDL-47W808A TV, it is advisable to start with an external examination of its external and internal elements. It often happens that visible damage to elements or connections helps determine the direction of the troubleshooting. In some cases, faulty elements can be seen with the naked eye, for example, charred resistors or swollen metal-ceramic capacitors, or electrolytic in rectifier filters. Ring cracks formed in the soldered terminals of transformers or heating elements of the circuit are also frequent sources of many malfunctions with a variety of external manifestations.
In cases when the SONY KDL-47W808A TV does not turn on, does not respond to the remote control and buttons, no indicators on the front panel light up or blink, and there are no sounds and no signs of operability when turning on, the APS-342 power supply module is most likely faulty or there is no power to the processor on the motherboard (a typical defect of some models of SONY TVs). Diagnostics and repair of the common power supply should always begin with a check of the mains fuse and the condition of the electrolytic capacitors of the secondary rectifier filters. Defective and swollen capacitors should be replaced with new ones. If the fuse breaks, it is advisable to check for a breakdown, first of all, all the power semiconductor elements of the converter and the diode bridge of the rectifier network, as well as the large electrolytic capacitor of the filter of the rectifier network.
It should be remembered that in the practice of repair, usually the power switches in switching power supplies (SMPS) do not fail due to their poor quality and, in such cases, it is necessary to look for the cause that led to a malfunction and provoked a breakdown of the key. Most often, the culprits of the accident are dried electrolytic capacitors or dangling resistors in the primary circuit, or the microchip of the PWM controller MIP2H2 dezh can be faulty. It is also necessary to check all the semiconductor elements of the stabilization circuit in the primary and secondary circuits.
If the SONY KDL-47W808A TV does not have an image, but there is sound, a malfunction in the LED backlight circuits of the LC470EUF FF P2 panel is likely. It is also necessary to check the serviceability of the electrolytic capacitors of the filter of the secondary rectifiers of the BP (power supply) for an overstated ESR.
Often there is a need for disassembling the panel to check the health of the LEDs, as well as contact connections in the connectors and soldering.
A break in the line of LEDs connected in series cannot be detected with a multimeter or tester without disassembling the panel. To open all the transitions, several tens of volts are needed, and it is best to use a current source for such purposes.
Remember! Attempts to self-repair by users of the SONY KDL-47W808A TV without the appropriate qualifications and necessary experience can lead to serious negative consequences!
Service manual / schematic diagram -------------> Sony KDL-42W802A/805A/807A, KDL-42W808A/809A, KDL-47W802A/805A/807A/808A/809A, KDL-55W802A/805A/807A/808A/809A chassis RB1G; KDL-42W802A, KDL-42W805A, KDL-42W807A, KDL-42W808A, KDL-42W809A, KDL-47W802A, KDL-47W805A, KDL-47W807A, KDL-47W808A, KDL-47W809A, KDL-55W802A, KDL-55W805A, KDL-55W807A, KDL-55W808A, KDL-55W809A
The appearance of MainBoard 1-888-101-41 is shown in the figure below:1-888-101-41
1-888-101-41 can be used in TVs:
SONY KDL-47W808A (Panel LC470EUF FF P2), SONY KDL-55W808A (Panel LC550EUF FF P2).
PSU Advanced
According to the conditions of compliance with modern world standards for household switching power supplies, the APS-342 module provides for the use of a Power Factor Correction unit. The PFC circuit is a flyback converter based on the CXA3810M & PWM resonant PWM controller. The reactance of an electrolytic capacitor of a line filter at a frequency of 50-60 Hz is usually not more than 20-30 ohms and its charge directly from the network through open diodes could reach tens of amperes per pulse if no filtering were applied.
As a result of the PFC conversion, an increased voltage on the capacitor (about 380V) cannot directly open the rectifier diodes, on the anode of which the voltage will always be slightly less (about 300V) and then its charging current will always be limited by the elements of the PWM controller. As a result, the envelope of the high-frequency pulses of the consumed current will repeat the shape and phase of the input sinusoidal voltage. The presence of an increased voltage (+ 380V) on the network capacitor indicates the serviceability of the PFC node.
The appearance of the power supply
Main features of the device SONY KDL-47W808A:
Installed matrix (LED-panel) LC470EUF FF P2.
To power the backlight LEDs, a converter is used, combined with a power supply, controlled by a CXA3854M PWM controller. As power elements of the LED driver, keys of the MDF3N50 type are used.
The necessary supply voltages for all nodes of the SONY KDL-47W808A TV are generated by the APS-342 power supply module or its analogs using CXA3810M (PFC & PWM resonant), MIP2H2 (StandBy) microcircuits and power switches of the KF7N50F, TK15A50D (PFC) type.
MainBoard - the main board (motherboard) is a module 1-888-101-41, using CPU chips: CXD4739GB; NAND Flash: TC58DVG3S0ETA00 and others.