Technical description and composition of the SAMSUNG LE26B350F1WXRU TV, panel type and applicable modules. The composition of the modules.SAMSUNG
Model: LE26B350F1WXRU LE26B350F1W
Chassis / Version: N76A
Panel: T260XW02 V.S // LTF260AP03
T-CON: T260XW02 VS 26T02-C07
Inverter (backlight): BN44-00291A
PWM Inverter: BD9893F (16)
MOSFET Inverter: 1K46DC, LT-HU26
Power Supply (PSU): BN44-00291A
PWM Power: ICE3BR0665J (Standby), FAN7530 (PFC)
MainBoard: BN41-01207C BN94-03159H (SURVIVAL_DVB)
IC MainBoard: K4T51163QG-HCE7, MX25L6405DMI-12G, NTP3200
Tuner: BN40-00150A DTX-8B / W12B5S
Control: Remote: BN59-00942A; IR: BN41-01208A ET090608
Specifications LE26B350
SAMSUNG LE26B350F1WXRU
General repair guidelines for TV LCD
SAMSUNG LE26B350F1W X (RU) TV, and similar versions of this model, it is advisable to start repairing with a careful inspection of internal and external elements. Sometimes, for some visible changes, you can determine the further direction of the defect search and localization of the malfunction before the start of taking the oscillograms and making the necessary measurements at the control points. Experienced repairmen are often aware of the causes of the defect and the possible consequences, for example, from ring cracks in the soldering of the leads of the elements, as well as from swollen capacitors or resistors burnt to coal dust and other external indirect signs.
If the TV does not turn on, no indicators on its front panel are lit or blinking. Also, if the TV does not respond to the remote control and buttons, does not make any sounds or any signs of operability when turned on, there is a certain chance that the BN44-00291A power supply module is defective and needs repair. Sometimes with similar manifestations, a problem can only occur in the absence of processor power, but this happens much less often. When diagnosing and repairing the power supply, first of all, it is necessary to check the fuse and, if it is broken, it is necessary to identify the cause. Often in such cases, an avalanche (thermal) breakdown is detected in the power semiconductor elements of the module - rectifier diodes or power key.
If a breakdown of the power switch of the flyback converter of the power supply unit is detected, it should be remembered that it does not fail without any reasons that should be sought by checking other elements of the primary circuit - electrolytic capacitors, PWM controller ICE3BR0665J, FAN7530, which can only be checked by replacement, and also other semiconductor elements (diodes, transistors, zener diodes).
In cases using a power module with an active KKM, troubleshooting is sometimes somewhat more complicated.
In the circuitry of the SAMSUNG LE26B350F1W X (RU) TV, a single power supply and inverter are used, which are combined into one common module BN44-00291A. When repairing by replacing components, this circuitry option does not complicate the search for defects and is popular in the latest TV models from many manufacturers.
If there is no image when you turn on the SAMSUNG LE26B350F1WXRU, or it appears for a second and disappears completely, but there is sound, most likely either the backlight or the power converter (inverter) are faulty. It is necessary to check the electrolytic capacitors of the filter of the secondary rectifiers in the general power supply unit.
Repair of the BN44-00291A inverter can often be somewhat complicated by the use of special protection circuits, which are designed to disconnect it in emergency cases for fire safety when the lamps are depressurized, or short circuits or breaks in high-voltage circuits and connections. Sometimes it becomes necessary for diagnostic purposes to block the protection circuits in order to be able to make the necessary measurements at the control points of the circuit.
In such cases, the risk of failure of the power elements of the inverter is most likely, and special care is required during work, and after their completion, it is necessary to restore the protection circuit for further safe operation of the TV by the owner in normal mode.
In cases of attempts to repair the motherboard BN94-03159H (SURVIVAL_DVB), it is necessary to check the operability of the power supply stabilizers of the microcircuits and, if possible, update 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, for example, K4T51163QG-HCE7, MX25L6405DMI-12G, NTP3200, Tuner DTX-8B / W12B5S, as well as other defective components .
Owners and users of the SAMSUNG LE26B350F1W TV must 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!
The appearance of the MainBoard BN41-01207C is shown in the figure below:BN41-01207C
BN41-01207C can be used in TVs:
SAMSUNG LE26B350F1WXRU (Panel T260XW02 V.S), SAMSUNG LE32B350F1W (Panel LTF320AP06), SAMSUNG LE32B350F1 (Panel LTF320AP06 A16).
PSU Advanced
The power module BN44-00291A is made using a power factor correction circuit (PFC - Power Factor Correction) in order to eliminate multiple AC harmonics introduced by the device into the mains. The PFC assembly is a Step-Up Converter based on a FAN7530 PWM controller that evenly distributes high-frequency impulses of the charging current of the electrolytic capacitor of the rectifier filter of the mains voltage over a period of 50 Hz. The current of its charge in this case will already be determined not by its reactance (usually 10-30 ohms for the network frequency), but by the elements of the converter. As a result, a change in the amplitude of the pulses (envelope) of the consumed current of the converter will repeat the shape and phase of the input sinusoidal voltage. The availability of the increased voltage (about + 380V) in the operating mode on the capacitor of the line filter indicates the serviceability of the PFC node.Main features of the SAMSUNG LE26B350F1WXRU device:
Installed matrix (LCD panel) T260XW02 V.S or LTF260AP03.
The matrix control uses the Timing Controller (T-CON) T260XW02.
To power the backlight, an inverter BN44-00291A is used, it is controlled by the BD9893F PWM controller (16). As power elements of the inverter, keys of the type 1K46DC, LT-HU26 are used.
The necessary supply voltages for all nodes of the TV SAMSUNG LE26B350F1WXRU are generated by the power module BN44-00291A, or its analogs using ICE3BR0665J (Standby), FAN7530 (PFC) microcircuits.
MainBoard - the main board (motherboard) is a BN41-01207C module, using K4T51163QG-HCE7, MX25L6405DMI-12G, NTP3200 and others.
Tuner BN40-00150A DTX-8B / W12B5S provides the reception of television programs and tuning to channels.
