Friday 27 December 2019

REPAIRING / SERVICING TV SAMSUNG LE40B531

Technical description and composition of the SAMSUNG LE40B531 TV, panel type and applicable modules. The composition of the modules.
SAMSUNG
Model: LE40B531 LE40B531P7W
Chassis / Version: N65A
Panel: LTF400HA08
T-CON: FHD60C4LV1.0 / FHD60C4LV1.1
Inverter (backlight): integrated into PSU
PWM Inverter: BD9893
MOSFET Inverter: STP9NK50ZFP
Trans Inverter: QGAH02101
Power Supply (PSU): BN44-00264C
PWM Power: FAN7530 (PFC), 3BR1065JF
MOSFET Power: 11N60PFC, FQPF9N50C
MainBoard: BN41-01165A
IC MainBoard: CPU: SEMS12, DRAM: K4T511630G-HCE7, SPI Flash: 25L6405DMI-12G, NTP3200, MX25L6445D, WT61P8
Tuner: BN40-00137A
Specifications LE40B531
SAMSUNG LE40B531
General repair guidelines for TV LCD
Possible malfunctions
- SAMSUNG LE40B531 does not turn on. There are no signs of operability. The indicators on the front panel do not light or flash, the TV does not respond to the remote control and control buttons.
Often in such cases, the BN44-00264C power module is faulty. 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 (11N60PFC, FQPF9N50C) of converters 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 short circuit in the elements of the primary circuit, the mains fuse usually breaks.
The breakdown of power switches (MosFet) in pulsed sources is sometimes caused by malfunctions of other circuit elements, for example, in the circuits supplying the PWM controller, frequency-setting or damper ones, as well as in the circuits of Negative Feedback (OOS) stabilization. PWM controllers (PWM) FAN7530 (PFC), 3BR1065JF, if they do not have visible damage to the case and open fault between the terminals, are usually checked by replacement.
- There is no image, but there is sound, it reacts to the remote control. Or the image appears when you turn on and immediately disappears
These manifestations can be triggered by a power supply module, or by inverter defects, as well as a distortion of the currents in the lamps due to their uneven wear. If all the electrolytic capacitors of the filter according to the inverter power supply are serviceable, you should make sure that the lamps are in good working condition, then you need to check the converter keys and the secondary windings of the transformers.
Sometimes, for diagnostic purposes, it is necessary to disable the inverter protection. 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 on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the BN41-01165A 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, DRAM: K4T511630G-HCE7, SPI Flash: 25L6405DMI-12G, NTP3200, MX25L6445D, WT61P8 with new or obviously working ones. In cases where BGA technologies are used, defects are usually localized by the heating method.
Before replacing the tuner BN40-00137A, if there is no tuning to the channels, you must first check the software and the supply voltage at its terminals. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus
Once again, remind users! Attempts to self-repair a SAMSUNG LE40B531 TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!

SCHEMATICS --->  Samsung LE40B531P7W Chassis N65A.

FOR MODELS ----> LE32B53***, LE37B53***, LE40B53***, LE46B53***.

PSU SCHEMATICS ----->  BN44-00264C.


 The appearance of the MainBoard BN41-01165A is shown in the figure below:
BN41-01165A
BN41-01165A can be used in TVs:
SAMSUNG LE32B450C4 LE32B450C4W (Panel LTF320AP06), SAMSUNG LE37B530P7 LE37B530P7W (Panel AX094F040E), SAMSUNG LE40B530P7 LE40B530P7W (Panel LTF400HA08), SAMSUNG LE46B530P7 LE46B530P7W (Panel V460H1-L06 RevC1), SAMSUNG LE32B530 LE32B530P7W (Panel LTF320HA09), SAMSUNG LE40B531 LE40B531P7W (Panel LTF400HA08) .
The appearance of the power supply
Main features of the SAMSUNG LE40B531 device:
Installed matrix (LCD panel) LTF400HA08.
The matrix control uses the Timing Controller (T-CON) FHD60C4LV1.0.
To power the backlight, a converter is used, combined with a power supply, controlled by the BD9893 PWM controller. A transformer QGAH02101 is installed in the inverter converter. As power elements of the inverter, keys of the STP9NK50ZFP type are used.
The necessary supply voltages for all nodes of the TV SAMSUNG LE40B531 are generated by the power module BN44-00264C, or its analogs using microchips FAN7530 (PFC), 3BR1065JF and power switches of the type 11N60PFC, FQPF9N50C.
MainBoard - the main board (motherboard) is a BN41-01165A module, using CPU chips: SEMS12, DRAM: K4T511630G-HCE7, SPI Flash: 25L6405DMI-12G, NTP3200, MX25L6445D, WT61P8 and others.
The tuner BN40-00137A provides the reception of television programs and tuning to channels.