Saturday, 28 December 2019

REPAIRING / SERVICING TV SAMSUNG LE46D550K1

Technical description and composition of the SAMSUNG LE46D550K1 TV, panel type and applicable modules. The composition of the modules.
SAMSUNG
Model: LE46D550K1 LE46D550K1W
Chassis / Version: LE46D550K1WXRU; Version SQ03
Panel: LTF460HN01
T-CON: S100FAPC2L V0.3
Inverter (backlight): SST460 12A01
Trans Inverter: 340166AD
Power Supply (PSU): BN44-00441A Rev1.2 - I46F1_BHS
PWM Power: FSGM0465
MainBoard: BN41-01751A
IC MainBoard: K9F1G08U0D, 25Q40,24C256, K4B1G1646G-BCH9, D23330AC, WT61P805, DRV612
Tuner: DTOS40FVL082A BN40-00197A
Specifications LE46D550
SAMSUNG LE46D550K1
General repair guidelines for TV LCD
Any repair of electronic equipment begins with a careful external inspection of the device and troubleshooting. In this case, you should carefully examine all the elements of the SAMSUNG LE46D550K1 TV, both internal and external. Many changes visible to the naked eye make it possible to determine the future direction of troubleshooting and localization of the defect. Ring cracks in the soldering of the leads of the elements, deformed electrolytic capacitors, charred resistors - all this for the repairman can be a hint in assumptions about the causes and consequences of the malfunction.
Malfunctions of the power module I46F1_BHS BN44-00441A Rev1.2 can be expressed in different ways, for example, SAMSUNG LE46D550K1 does not turn on at all and the control lamps on its front panel do not light up and do not blink, and there are no signs of operability. When repairing the power supply, it is advisable to start the diagnostics by checking the mains fuse and, in the event of a break, the cause should be sought in the power semiconductor elements of the pulsed flyback converter of the main PSU. First of all, it is necessary to check the diodes of the bridge of the rectifier of the mains voltage and the power switch of the converter, which can be installed separately on the radiator, or integrated with a PWM controller.
As a rule, the keys of flyback converters, which use an N-Fet field effect transistor on a separate radiator, or integrated with a PWM controller in a single chip, are reliable enough and rarely fail for no reason. The reasons for the breakdown of the key should be sought by checking other components of the circuit - electrolytic capacitors, resistors and semiconductor elements of the primary circuit. The PWM chip is checked by replacing it with a known good one.
Diagnostics of power modules with a Power Factor Corrector (CMC) is somewhat more complicated and requires a more detailed approach.
If the SAMSUNG LE46D550K1 TV does not have an image, but there is sound, the malfunction should be sought in the power converter of the backlight (inverter). It is also necessary to check the serviceability of the electrolytic capacitors of the filter of the secondary rectifiers of the BP (power supply) for an overstated ESR.
When repairing the SST460 12A01 inverter, it is often necessary to disable the protection for diagnostics, which, for the purpose of fire safety, turns it off in any emergency situation, for example, during a malfunction or uneven wear of the lamps, which makes it difficult to find a defect.
When diagnosing with the protection off, special precautions must be taken, because there is a risk of failure of the power elements of the inverter. After the diagnosis, it is imperative to restore the protection circuits for the inverter to operate normally.
Diagnosis and repair of the BN41-01751 motherboard is carried out by checking the performance of power stabilizers and microcircuits, as well as by updating the software (software).
Owners and users of the SAMSUNG LE46D550K1 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!

SCHEMATIC ----------> Samsung LE(LE)46D550 Chassis U56A, U56B.

 The appearance of the MainBoard BN41-01751A is shown in the figure below:
BN41-01751A
BN41-01751A can be used in TVs:
SAMSUNG LE32D551K2 LE32D551K2W (Panel LTF320HN01), SAMSUNG LE46D550K1 LE46D550K1W (Panel LTF460HN01), SAMSUNG LE40D551 LE40D551K2W (Panel LTF400HM03), SAMSUNG LE46D551 LE46D551 LE.
The appearance of the power supply
Main features of the SAMSUNG LE46D550K1 device:
Installed matrix (LCD panel) LTF460HN01.
The matrix control uses the Timing Controller (T-CON) S100FAPC2L.
To power the backlight used inverter SST460. The transformer 340166AD is installed in the inverter converter.
The formation of the necessary supply voltages for all nodes of the SAMSUNG LE46D550K1 TV is carried out by the BN44-00441A power module, or its analogs using FSGM0465 microcircuits.
MainBoard - the main board (motherboard) is a module BN41-01751A, using microchips K9F1G08U0D, 25Q40,24C256, K4B1G1646G-BCH9, D23330AC, WT61P805, DRV612 and others.
Tuner DTOS40FVL082A BN40-00197A provides the reception of television programs and tuning to channels.
Information from an alternative source:
SAMSUNG LE46D550K1W Model Code: LE46D550K1WXRU; Version SQ03
Panel Type (Matrix): LTF460HN01
Motherboard: BN41-01751, Tuner: DTOS40FVL082A BN40-00197A
T-con: S100FAPC2L V0.3,
Invertor: SST460 12A01,
PSU: I46F1_BHS BN44-00441A Rev1.2
Additional technical information about the panel:
Brand: SAMSUNG
Model: LTF460HN01
Type: a-Si TFT-LCD, Panel
Diagonal size: 46 inch
Resolution: 1920x1080, FHD
Display Mode: S-PVA, Normally Black, Transmissive
Active Area: 1018.08x572.67 mm
Surface: Antiglare (Haze 5.5%), Hard coating (2H)
Brightness: 450 cd / m²
Contrast Ratio: 5000: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 8 (G to G)
Frequency: 60Hz
Lamp Type: 12 pcs CCFL Embedded (Balance board)
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V