Technical description and composition of the TV SHARP LC-40LE340RU, type of panel and applicable modules. The composition of the modules.SHARP LED
Model: LC-40LE340RU
Chassis / Version: 17MB70-5B
Panel: LTA400HM13
LED driver (backlight): integrated into PSU
Power Supply (PSU): 17PW07-2
PWM Power: FAN7621 (PWM resonant), FAN7529 (PFC), FSDL321 (Standby), NCP1579 (Step-Down)
MOSFET Power: FQPFN50C, AO4842
MainBoard: 17MB70-5B
IC MainBoard: CPU: BCM3556FKFSB5G TE1206 P30; NAND Flash: K9F1G08UOD;
Tuner: TDTC-G605D
Appearance
SHARP LC-40LE340RU
General repair guidelines for TV LCD LED
Repair and diagnostics of any electronic device, in particular SHARP LC-40LE340RU, it is advisable to start with a careful external examination of internal and external elements. It often happens that visible damage to elements or connections helps determine the direction of the troubleshooting. Swollen electrolytic or cermet capacitors, charred resistors, ring cracks in the soldered terminals of the elements - all this can significantly help the master to determine the causes and consequences of the malfunction of the TV.
If the power supply module 17PW07-2 is faulty, the external manifestations may be different, for example, the SHARP LC-40LE340RU does not turn on at all and there is no indication of the indicator lights on the front panel. When repairing the power supply, it is advisable to start the diagnostics by checking the mains fuse and the electrolytic capacitors of the filters of the converter secondary rectifiers. In the event of a fuse breaking, the reason should be sought in the power semiconductor elements of the pulse converter of the main power supply. First of all, it is necessary to check the diodes of the rectifier bridge of the mains voltage and the power key (s) of the converter. The complete inoperability of the power supply unit can be caused by a short circuit in the power elements in the primary circuit, followed by an open fuse, or a short circuit in the loads.
Power switches in pulsed power supplies (SMPS) 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 there is no image when you turn on the SHARP LC-40LE340RU, or it appears and immediately disappears, but there is sound, most likely there is a malfunction in the backlight LED circuit of the LTA400HM13 panel, or in their power converter.
A malfunction in the backlight circuits often occurs due to an open in the power circuit of the LED lines. It requires disassembling the panel and checking the LEDs themselves, the soldering of their outputs, as well as the reliability of the connections in the connectors and the soldering of the conclusions of the connectors.
To detect a break in the LED lines without disassembling the panel, a current source is required. It is impossible to open transitions connected in series with a simple multimeter; voltage of several tens of volts is necessary.
If the motherboard 17MB70-5B is faulty, first of all it is necessary to check all the linear stabilizers and power converters of its chips, as well as, if necessary, update the software (software). Sometimes you can check the health of MB only by replacement.
In cases of attempts to repair the MB (SSB) board, it is necessary to check the health of its elements - CPU: BCM3556FKFSB5G TE1206 P30; NAND Flash: K9F1G08UOD; which may require replacement with new ones. If a BGA processor is installed, there is a possibility of a violation of the soldering of the contacts of its conclusions with the board (it is diagnosed by heating).
If there is no reception of television channels, but the TV is working properly from external devices, first of all you need to check the power supply of the tuner TDTC-G605D and update the software.
It should be remembered! Attempts to repair the TV SHARP LC-40LE340RU, 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 manual / schematic diagram -----------------------------> Power Vestel 17PW07-2 Schematic diagram
The appearance of the MainBoard 17MB70-5B is shown in the figure below:17MB70-5B
PSU Advanced
The 17PW07-2 power module is installed in the LC-40LE340RU 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 FAN7529 PWM controller does not allow the input rectifier filter's electrolytic capacitor to be connected directly to the network directly through open diodes, when the value of the charge current determines its reactance (about 15-30 ohms at a frequency of 50 Hz). 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-40LE340RU device:
Installed matrix (LED-panel) LTA400HM13.
To power the backlight LEDs, a converter is used, combined with a power supply.
The necessary supply voltages for all nodes of the SHARP LC-40LE340RU TV are generated by the 17PW07-2 power module or its analogs using FAN7621 (PWM resonant), FAN7529 (PFC), FSDL321 (Standby), NCP1579 (Step-Down) microcircuits and power switches type FQPFN50C, AO4842.
MainBoard - the main board (motherboard) is a 17MB70-5B module using CPU chips: BCM3556FKFSB5G TE1206 P30; NAND Flash: K9F1G08UOD; and others.
The TDTC-G605D tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: SAMSUNG
Model: LTA400HM13
Type: a-Si TFT-LCD, Panel
Diagonal size: 40 inch
Resolution: 1920x1080, FHD
Display Mode: S-PVA, Normally Black, Transmissive
Active Area: 885.6x498.15 mm
Surface: Antiglare
Brightness: 400 cd / m²
Contrast Ratio: 4000: 1
Display Colors: 16.7M (8-bit), CIE1931 70%
Response Time: 8 (G to G)
Frequency: 60Hz
Lamp Type: WLED Embedded (LED Driver)
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V