Technical description and composition of the SAMSUNG LE40S71B TV, panel type and applicable modules. The composition of the modules.SAMSUNG
Model: LE40S71B
Chassis / Version: SP04
Panel: LTA400WT-L01
T-CON: 3240WTC4LV0.5
Inverter (backlight): HI40024W21-B Rev.07, HI40024W21-H Rev.07
PWM Inverter: LX1691A, FAN7382
Power Supply (PSU): BN44-00134A HU09364-5003B 3925310002AD
PWM Power: ICE1PCS02, ICE3B0365J, FSDM07652RB, LX1691A, FAN7382
MOSFET Power: SPW12N50C3, FQPF11N50CF
MainBoard: BN41-00758A BN91-01117B
IC MainBoard: MT8202EG, 24C32WP, 74HC4052D, 9933B, A21SC, A81SC, AP358, MAX232ECW, MP1583DN
Tuner: BN40-00079A
Control: IR: BN41-00711A
Technical specifications LE40S71B
SAMSUNG LE40S71B
General repair guidelines for TV LCD
Possible manifestations of defects
- The SAMSUNG LE40S71B TV does not turn on and does not show any signs of turning on, it does not respond to the control buttons or the remote control.
In such cases, the BN44-00134A power supply is usually faulty. It is necessary to verify the presence of its output voltages and, if they are completely absent, check the power switches (SPW12N50C3, FQPF11N50CF) and rectifier diodes for possible short circuit.
In case of breakdowns in the secondary circuits, the converter can operate in a short circuit mode, and during a short circuit in the elements of the primary circuit, the mains fuse usually breaks.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can put it out of operation in key mode or provoke an excess of the maximum current or voltage. These can be circuits supplying the PWM controller, damping or frequency-setting circuits, or elements of OOS (negative feedback) in the stabilization circuit. PWM controllers (PWM) ICE1PCS02, ICE3B0365J, FSDM07652RB, LX1691A, FAN7382, in the absence of external damage and short circuit between the terminals, are checked by replacing with obviously good ones.
- There is no image, but there is sound and reaction to the remote control. Or for a second, the image may appear immediately after switching on.
These manifestations can be triggered by a power supply module, or by inverter defects, as well as distortion of the currents in the lamps due to their uneven wear. After checking all the electrolytic capacitors of the filters that are involved in the power supply of the inverter, it is necessary to ring in its converter the power switches for breakdown and the secondary windings of transformers for an open.
Sometimes, for diagnostic purposes, inverter protection must be disabled. In such cases, special care must be taken during work, and the protection circuits should be restored immediately after the repair is completed.
- The indicator blinks or glows constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the BN41-00758A motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, you should update or replace the software (software). In cases of complex repairs of MB (SSB) and in the presence of the necessary skills and equipment, sometimes it may be necessary to replace its chips MT8202EG, 24C32WP, 74HC4052D, 9933B, A21SC, A81SC, AP358, MAX232ECW, MP1583DN and other possible faulty components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
If a tuner BN40-00079A is suspected of malfunction, first of all, it is necessary to verify the correctness of the software, as well as the presence of the necessary voltage levels and impulses of data exchange with the processor via the I2C bus at the corresponding terminals of the tuner.
Owners and users of the SAMSUNG LE40S71B TV should 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!
SCHEMATICS PSU Samsung BN44-00134A Power supply.
The appearance of the MainBoard BN41-00758A is shown in the figure below:BN41-00758A
BN41-00758A can be used in TVs:
SAMSUNG LE32S71BX (Panel CLAA320WB02), SAMSUNG LE37R72BX (Panel CLAA370WA03S), SAMSUNG LE40S71B (Panel LTA400WT-L01).
The appearance of the power supply
Main features of the SAMSUNG LE40S71B device:
Installed matrix (LCD-panel) LTA400WT-L01.
The matrix control uses the Timing Controller (T-CON) 3240WTC4LV0.5.
To power the backlight, an inverter HI40024W21-B is used, controlled by a PWM controller LX1691A, FAN7382.
The necessary supply voltages for all nodes of the SAMSUNG LE40S71B TV are generated by the BN44-00134A power module or its analogs using ICE1PCS02, ICE3B0365J, FSDM07652RB, LX1691A, FAN7382 microchips and power switches of the SPW12N50C3, FQPF11N50CF type.
MainBoard - the main board (motherboard) is a BN41-00758A module, using chips MT8202EG, 24C32WP, 74HC4052D, 9933B, A21SC, A81SC, AP358, MAX232ECW, MP1583DN and others.
The tuner BN40-00079A provides the reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: SAMSUNG
Model: LTA400WT-L01
Type: a-Si TFT-LCD, Panel
Diagonal size: 40 inch
Resolution: 1366x768, WXGA
Display Mode: S-PVA, Normally Black, Transmissive
Active Area: 885.168x497.664 mm
Surface: Antiglare (Haze 44%), Hard coating (3H)
Brightness: 450 cd / m²
Contrast Ratio: 600: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 15/8 (Tr / Td)
Frequency: 60Hz
Lamp Type: 22 pcs CCFL Without Driver
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V