Technical description and composition of the TV SHARP LC-42SA1RU, type of panel and applicable modules. The composition of the modules.SHARP
Model: LC-42SA1RU
Chassis / Version: KD890
Panel: 42 inch
Inverter (backlight): V1838..381 V1838.371 / C2
PWM Inverter: MIC4427 (8) OZ364SN (20)
MOSFET Inverter: P2804ND5G (5) NIKOS 9563GH
Power Supply (PSU): DPS-263AP RDENCA193WJQZ
PWM Power: L6562 (PFC), DAS01A, DLA001 (PWM Push-pull), DAP011 (PWM Flyback), LM358
MainBoard: KD890 DUNTKD890FM17
IC MainBoard: VCT69936 B3000, MP1410ES, EPM24, Si19021CTU, CM052B, PIC16F913, FRC9429AB2
Tuner: DUNTKD608WE
Control: GA531WJSA
Technical Specifications LC-42SA1E
SHARP LC-42SA1RU
General recommendations for repairing TV LCD
Repair of the SHARP LC-42SA1RU TV is better to begin with a thorough external inspection and diagnosis of the malfunction. It is advisable to carefully examine the internal and external components. Often, by the external signs and nature of some damage, it is possible to draw preliminary conclusions and determine a further algorithm for 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.
If the power supply module RDENCA193WJQZ DPS-263AP is malfunctioning, the external manifestations may be different, for example, the SHARP LC-42SA1RU does not turn on at all and there is no indication of the indicator lights on the front panel. In this case, first of all, it is necessary to check the fuse at the mains input. If it is broken, then you should check for breakdown of the PN junctions of the rectifier bridge diodes and the key transistor of the N-FET converter, which can either be on a separate radiator or integrated with a PWM controller in a common chip. Possible options.
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.
In cases using a power module with an active KKM, troubleshooting is sometimes somewhat more complicated.
If the SHARP LC-42SA1RU has no image, but there is sound, there is a possibility of a malfunction of the backlight or power converter. You should also make sure that the electrolytic capacitors of the secondary rectifiers of the common power supply are working.
When repairing the inverter V1838..381 V1838.371 / C2, it is often necessary to disable the protection for diagnostics, which, for the purpose of fire safety, turns it off in any emergency situation, for example, during a malfunction or uneven wear of the lamps, which makes it difficult to find a defect.
All necessary precautions must be observed when disabling the inverter protection during diagnostics and not leaving it disconnected after the repair is completed.
Repair of the DUNTKD890FM17 main motherboard should begin with the diagnosis and verification of all linear stabilizers or power converters of its microcircuits. Sometimes it may be necessary to update the software (software) - flashing FLASH or EEPROM.
Once again, remind users! Attempts to self-repair a TV SHARP LC-42SA1RU without the appropriate qualifications and experience can lead to its complete non-repairability!
Service manual / schematic diagram -------------------> Sharp LC-42SA1E, LC-42SA1RU
The appearance of the MainBoard KD890 is shown in the figure below:Kd890
PSU Advanced
The DPS-263AP power module is installed on the LC-42SA1RU TV using the PFC (Power Factor Correction) scheme acting as an active filter to eliminate the higher harmonic components of the current consumption. The boost converter based on the L6562 PWM controller does not allow the input rectifier filter's electrolytic capacitor to be connected to the network directly through open diodes when the reactance (about 15-30 ohms at a frequency of 50 Hz) determines the charge current. As a result of the conversion, the charging current of the capacitor will be determined in such a way that the envelope of the high-frequency pulses of the input current will repeat the phase and shape of the sine wave of the input voltage. The health check of the PFC unit is carried out by measuring the DC voltage on the capacitor of the rectifier network. In operating mode, it should be around 380V, in standby approximately 300V.
The appearance of the power supply
Main features of the SHARP LC-42SA1RU device:
Installed matrix (LCD-panel) 42 inches.
To power the backlight, an inverter V1838..381 is used, it is controlled by the PWM controller MIC4427 (8) OZ364SN (20). As power elements of the inverter, keys of the type P2804ND5G (5) NIKOS 9563GH are used.
The necessary supply voltages for all nodes of the SHARP LC-42SA1RU television are generated by the DPS-263AP power supply module or its analogs using microcircuits L6562 (PFC), DAS01A, DLA001 (PWM Push-pull), DAP011 (PWM Flyback), LM358.
MainBoard - the main board (motherboard) is a KD890 module, using VCT69936 B3000, MP1410ES, EPM24, Si19021CTU, CM052B, PIC16F913, FRC9429AB2 and other chips.
The DUNTKD608WE tuner provides television reception and channel tuning.
LCD TV SHARP LC-42SA1E with a 42 "(106 cm) diagonal LCD display in 16: 9 format. The brightness of the screen is 450 cd / m² by CCFL (EEFL) fluorescent lamps. Contrast as the ratio of maximum brightness to minimum not less than 1200: 1.
You can view images in high quality HD at a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready). The input high-frequency or video signal can be processed in analogue systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in the standards 480i, 480p, 576i, 576p, 720p, 1080i.
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, SCART x2, RGB, VGA, HDMI, RS-232. 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.
The power consumed by the TV from the network in operating mode is 200 watts.
Overall dimensions: with stand 1029x768x304 mm, without stand 1029x709x133 mm.
TV Weight: with stand: 33.2 kg, without stand: 29.6 kg.
Attention! The LCD TV panel SHARP LC-42SA1E is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!