Technical description and composition of the SAMSUNG LE40B620R3W TV, panel type and applicable modules. The composition of the modules.SAMSUNG
Model: LE40B620R3W
Chassis / Version: N68A
Panel: LTF400HF12
T-CON: 2009FA7M4C4LV0.9
Inverter (backlight): integrated into PSU
PWM Inverter: SEM2006
MOSFET Inverter: 7N50
Power Supply (PSU): BN44-00264A 40F1_9SS
PWM Power: FAN7530, STR-W6252
MOSFET Power: FCPF11N60
MainBoard: BN41-01258B BN94-02694C
IC MainBoard: CPU: SEMS12, EEPROM: 24C1024, SPI FLASH: 25L6405DMI
Tuner: BN40-00137A
Control: IR: BN41-01194A, BN41-01193A
Specifications LE40B620
SAMSUNG LE40B620R3W
General repair guidelines for TV LCD
Possible manifestations of defects
- The SAMSUNG LE40B620R3W TV does not turn on, does not respond to the remote control and the control panel buttons, does not light up or blink indicators.
With such manifestations, the BN44-00264A power module usually fails. It is necessary to measure its output voltages, and in case of their absence (full or partial), it is necessary to check the serviceability of power switches (FCPF11N60) of converters and rectifier diodes for the presence of a possible short circuit.
In case of breakdowns in the secondary circuits, the converter, as a rule, can emergency work in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse usually breaks.
Mos-Fet power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. FAN7530, STR-W6252 PWM controllers, in the absence of visible damage or frank short-circuit between the terminals, are checked by replacing with new ones, or obviously working.
- There is no image, but there is sound and reaction to commands from the remote control. Or the image appears immediately after turning on and disappears.
The defect can be caused by problems in the nodes or elements of the backlight of the display, or in the power supply of the lamps or inverter. If all the electrolytic capacitors of the filter for the power supply of the inverter are working, make sure that the lamps are working, then you need to check the converter keys and the secondary windings of the transformers.
If in diagnosing a malfunction, it is necessary to disable the inverter protection, there is a risk of failure of the power elements of the inverter, and special care is required during operations, and after their completion, it is necessary to restore the protection circuits for further safe operation of the TV by the owner in normal mode.
- The indicator blinks or glows constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the BN41-01258B 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 some cases, to repair the MB board (SSB), it may be necessary to replace the chips - CPU: SEMS12, EEPROM: 24C1024, SPI FLASH: 25L6405DMI with new or obviously working ones. In cases where BGA technologies are used, defects are usually localized by the heating method.
Before changing the tuner BN40-00137A, if there is no possibility of tuning to television channels, you should make sure that there are supply voltages that must be measured at the corresponding terminals of the tuner and check the software for correctness. The pulses of the data exchange of the tuner with the processor can be controlled by an oscilloscope
TV users and owners must remember that attempts to self-repair a SAMSUNG LE40B620R3W TV without the appropriate qualifications and the necessary experience can lead to serious negative consequences!
SCHEMATICS ------> Samsung LE40B620 Chassis N68A.
FOR MODELS-------->: LE32B55*, LE37B55*, LE40B55*, LE46B55*, LE32B65*, LE37B65*, LE40B65*, LE46B65*, LE55B65*, LE32B57*, LE37B57*, LE40B57*, LE46B57*, LE32B67*, LE37B67*, LE40B67*, LE46B67*, LE55B67*, LE40B62*, LE46B62*, LE52B62*, LE40B75*, LE46B75*, LE52B75*
The appearance of the MainBoard BN41-01258B is shown in the figure below:BN41-01258B
Main features of the SAMSUNG LE40B620R3W device:
Installed matrix (LCD-panel) LTF400HF12.
The matrix control uses the Timing Controller (T-CON) 2009FA7M4C4LV0.9.
To power the backlight, a converter is used, combined with a power supply, controlled by a PWM controller SEM2006. As power elements of the inverter, keys of the 7N50 type are used.
The necessary supply voltages for all nodes of the SAMSUNG LE40B620R3W TV are generated by the BN44-00264A power module or its analogs using FAN7530, STR-W6252 microcircuits and power switches of the FCPF11N60 type.
MainBoard - the main board (motherboard) is a BN41-01258B module using CPU chips: SEMS12, EEPROM: 24C1024, SPI FLASH: 25L6405DMI and others.
The tuner BN40-00137A provides the reception of television programs and tuning to channels.