REPAIR / SERVICING TV SHARP LC-47SB57UT

Technical description and composition of the SHARP LC-47SB57UT TV, panel type and applicable modules. The composition of the modules.
SHARP
Model: LC-47SB57UT
Panel: V470H2-LH2
Power Supply (PSU): 715G2802-P01-002-003S
PWM Power: ICE2PCS02G (PFC), LD7522PS, L6599D (PWM Resonant)
MOSFET Power: STW20NM60, 2SK4100LS
MainBoard: 9JR47SB57UT03
IC MainBoard: ZR39785HGCF, H5PS5162FFR-25C, MX25L3205DMI-12G, M24C64, TPA3123
Tuner: ENV56S02D8F
Appearance
SHARP LC-47SB57UT
General recommendations for repairing TV LCD
Repair SHARP LC-47SB57UT must begin with the diagnosis of the malfunction and a thorough inspection of its external and internal components, including the case. Sometimes, only by some signs can we determine the further direction of the localization of the malfunction. Experienced repairmen are often aware of the causes of the defect and the possible consequences, for example, from ring cracks in the soldering of the leads of the elements, as well as from swollen capacitors or resistors burnt to coal dust and other external indirect signs.
In the absence of any signs of operability, when the SHARP LC-47SB57UT does not turn on and does not signal anything with the control lights on the panel, the power supply module 715G2802-P01-002-003S is most likely faulty. In this case, the diagnosis and repair of the common power supply should always be started by checking the mains fuse. When it breaks, it is advisable to check for a breakdown, first of all, all power semiconductor elements of the converter and the rectifier diode bridge of the network, as well as the large electrolytic capacitor of the filter of the network rectifier and the key transistor.
Power switches in flyback converters fail extremely rarely for no reason and, if they are broken, it is necessary to look for a malfunction in the stabilization circuits by checking electrolytic capacitors, semiconductor devices, and resistors in the primary circuit. The cause may be a malfunction of the PWM controller chip, which can only be checked by replacing it with a new or obviously working one.
If the power module uses an active KKM circuit (power factor control), troubleshooting is somewhat more complicated.
Sometimes the SHARP LC-47SB57UT TV does not have an image, but there is sound, or the image appears and immediately disappears. In this case, there is a high probability of a malfunction of the backlight converter, or of the lamps themselves, which can be checked by replacement. In such cases, it is necessary to verify the serviceability of all electrolytic capacitors of the filter according to the power supply of the inverter itself, including the power supply unit (power supply unit).
Diagnostics of the inverter can be difficult due to the operation of the protection, which is organized by the designers to prevent negative consequences or fires in emergency cases, for example, during short circuits or breaks in the lamp power supply circuit, as well as their possible depressurization. To make the necessary measurements at control points or take the necessary waveforms, repairmen have to block the protection circuits in order to be able to diagnose.
It should be remembered that when the protection is turned off, there is always a risk of failure of the power elements of the inverter during diagnosis. After repair, it is necessary to restore all standard converter protection circuits.

Owners and users of the SHARP LC-47SB57UT TV must remember that self-repair without special knowledge, skills and qualifications can be fraught with negative consequences that can lead to complete non-repairability of the device!

schematic / manual --------------------->  SHARP LC-47SB57UT

 The LC-47SB57UT model uses a 715G2802-P01-002-003S power supply unit using the PFC (Power Factor Correction) node - an active filter of higher harmonics of the current consumption. In fact, this is a boost converter based on the ICE2PCS02G PWM controller, which eliminates the charge current of the rectifier filter's electrolytic capacitor directly from the network through open diodes when its charging current is determined by its reactance.
As a result of the operation of the converter, the envelope of the high-frequency pulses of the input current of the converter will repeat the shape and phase of the input voltage. The health of the PFC node can be indirectly judged by the presence of an increased constant voltage (about + 380V) on the capacitor of the rectifier network in operating mode.
Main features of the SHARP LC-47SB57UT device:
Installed matrix (LCD panel) V470H2-LH2.
The necessary supply voltages for all nodes of the SHARP LC-47SB57UT TV are generated by the 715G2802-P01-002-003S power module or its analogs using ICE2PCS02G (PFC), LD7522PS, L6599D (PWM Resonant) microcircuits and power switches of the STW20NM60, 2SK4100LS type.
MainBoard - the main board (motherboard) is a 9JR47SB57UT03 module, using microchips ZR39785HGCF, H5PS5162FFR-25C, MX25L3205DMI-12G, M24C64, TPA3123 and others.
The tuner ENV56S02D8F provides reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: CMO
Model: V470H2-LH2
Type: a-Si TFT-LCD, Panel
Diagonal size: 47 inch
Resolution: 1920x1080, FHD
Display Mode: Super MVA, Normally Black, Transmissive
Active Area: 1039.68x584.82 mm
Surface: Antiglare (Haze 11%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 4000: 1
Display Colors: 16.7M / 1.07B (8-bit / 8-bit + Hi-FRC), CIE1931 72%
Response Time: 4.5 (G to G)
Frequency: 120Hz (60Hz Input)
Lamp Type: 12 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (2 ch, 8/10-bit), 51 pins
Voltage: 12.0V