Technical description and composition of the TV SHARP LC-42SB55RU, type of panel and applicable modules. The composition of the modules.SHARP
Model: LC-42SB55RU
Panel: V420H1-l07 c3
T-CON: V420H1-C07
PWM Inverter: BA2902F (14)
MOSFET Inverter: AO4614 (8)
Power Supply (PSU): 715T3150-2
MainBoard: 715T3251-4
IC MainBoard: SPI flash MX25L3205DMI-12G, EEPROM: M24C16WP, AUDIO: MT8292 & TDA8933BTW
Tuner: ENG37E14KF
Technical Specifications LC-42SB55
SHARP LC-42SB55RU
General recommendations for repairing TV LCD
Any repair of electronic equipment begins with an external inspection of the device and diagnostics of the malfunction. In this case, you should visually carefully examine all the elements of the SHARP LC-42SB55RU TV, both internal and external. Often, for certain external signs, the repairman can draw some conclusions about the reasons for the failure of certain elements of the circuit even before the necessary measurements are made, which will determine the further algorithm for troubleshooting and localizing the defect. 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.
Faults in the 715T3150-2 power module can be expressed in different ways, for example, the SHARP LC-42SB55RU does not turn on at all and the control lamps on its front panel do not light up and do not blink, and there are no signs of operability. When diagnosing and repairing the 715T3150-2 power supply, first of all, it is necessary to check the fuse, and if it is broken, the power switch and rectifier bridge diodes should be checked for avalanche (thermal) breakdown.
The reasons for the breakdown of the power switch of the flyback converter of the power module can be different, for example, a malfunction of semiconductor cells or electrolytic capacitors in the stabilization circuits of the primary circuit, as well as a failure in the operation of the PWM controller chip or breakage of the resistors in its bundle.
When using the Active Power Factor Correction (CMC) circuitry in the power module, the search for faulty elements is somewhat more complicated.
If the SHARP LC-42SB55RU does not have an image, there is sound and the channels switch, there is a possibility of a malfunction of the display backlight, or their power converter - inverter. Sometimes when you turn on the image appears and disappears immediately. In such cases, it is necessary to check the electrolytic capacitors of the power filter of the inverter itself, including in the secondary rectifier of the main PSU.
Repair of the inverter can often be somewhat complicated by the use of special protection circuits, which are designed to disconnect it in emergency cases for fire safety during depressurization of lamps, or short circuits or breaks in high-voltage circuits and connections. Sometimes it becomes necessary for diagnostic purposes to block the protection circuits in order to be able to make the necessary measurements at the control points of the circuit.
In such cases, special care should be taken when diagnosing, and after completion of all repair work, it is necessary to restore the circuit and the inverter protection for the further safe operation of the TV.
If the motherboard 715T3251-4 is faulty, first of all it is necessary to check all the linear power regulators of its chips and, if necessary, update the software. Sometimes you can check the health of MB only by replacement.
If the TV works normally from external devices, but does not tune into television channels, the ENG37E14KF tuner may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding terminals, as well as the power supply of varicaps (30-33V).
It should be remembered! Attempts to repair the SHARP LC-42SB55RU TV, in the absence of the necessary qualifications and experience, are categorically not recommended and are fraught with negative consequences, up to the complete non-repairability of the device!
Service Manuals with Schematic Diagrams 176 pages of 2008 LC-26SB25E, LC-26SB25S, LC-26SB25RU, LC-32SB25E, LC-32SB25S, LC-32SB25RU, LC-42SB55E, LC-42SB55S, LC-42SB55RU.
The appearance of the MainBoard 715T3251-4 is shown in the figure below:715T3251-4
Main features of the SHARP LC-42SB55RU device:
Installed matrix (LCD panel) V420H1-l07 c3.
The matrix control uses the Timing Controller (T-CON) V420H1-C07.
A converter controlled by the BA2902F PWM controller (14) is used to power the backlight lamps. As power elements of the inverter, keys of the type AO4614 (8) are used.
The necessary supply voltages for all nodes of the SHARP LC-42SB55RU TV are generated by the 715T3150-2 power module, or its analogs.
MainBoard - the main board (motherboard) is a 715T3251-4 module, using microchips SPI flash MX25L3205DMI-12G, EEPROM: M24C16WP, AUDIO: MT8292 & TDA8933BTW and others.
The ENG37E14KF tuner provides TV reception and channel tuning.
Information from an alternative source:
SHARP LC-42SB55RU
Panel Type (Matrix): V420H1-L07 Rev. C3,
Motherboard: 715T3251-3 (WK: 827), Tuner: ENG37E14KF
T-con: V420H1-C07
Invertor: I420H1-20B-MASTER
Invertor: I420H1-20B-SLAVE
PSU: 715T3150-1
Remote control: RL57S
Additional technical information about the panel:
Brand: CMO
Model: V420H1-L07
Type: a-Si TFT-LCD, Panel
Diagonal size: 42 inch
Resolution: 1920x1080, FHD
Display Mode: Super MVA, Normally Black, Transmissive
Active Area: 930.24x523.26 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 2000: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 6.5 (G to G)
Frequency: 60Hz
Lamp Type: 20 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V
LCD TV SHARP LC-42SB55 with LCD display V420H1-l07, diagonal size 42 "(106 cm) 16: 9 format. Brightness of the screen glow 500 cd / m² organized by backlighting with CCFL fluorescent lamps (EEFL). Dynamic contrast ratio 10000: 1 achieved by controlling the backlight depending on the brightness of the plot.
The design and technical capabilities of the TV include watching programs and movies in high quality HD at a resolution of 1920x1080 pixels in a graphical decomposition according to the standard 1080p (Full HD). The input high-frequency or video signal can be processed in analogue systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p.
The power of the sound system 20 W (2x10 W) provides two speakers. It uses a NICAM stereo signal processing system and Sound Surround.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, audio x3, S-Video, component, SCART x2, RGB, VGA, HDMI x3. An output for connecting headphones is provided. To connect a computer or laptop to this TV model, a VGA (D-Sub 15) connector is used on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768, 1280x1024, 1360x768, 1920x1080.
A digital tuner is capable of receiving television channels in DVB-T standards.
The power consumed by the TV from the network in operating mode is 220 watts.
Overall dimensions: with stand 1009x694x270 mm, without stand 1009x654x99 mm.
TV Weight: with stand: 22.7 kg, without stand: 19.5 kg.
Attention! The SHARP LC-42SB55 LCD TV panel V420H1-l07 c3 is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!
