Technical description and composition of the SAMSUNG LE40L51BM TV, panel type and applicable modules. The composition of the modules.SAMSUNG
Model: LE40L51BM
Panel: LTA400W2-L01
T-CON: 400W2C4LTV0.1
Inverter (backlight): 24V40W2S (HIP0212A) REV4_1
PWM Inverter: DMB8110D
MOSFET Inverter: SI4942
Power Supply (PSU): BN94-00622J
PWM Power: STR-W6765, ICE1PCS02 (PFC), VIPer12A (Standby)
MainBoard: MAIN_PCB
Appearance
SAMSUNG LE40L51BM
General repair guidelines for TV LCD
Repair SAMSUNG LE40L51BM must begin with the diagnosis of the malfunction and a thorough inspection of its external and internal elements, including the case. Visible damage to elements can sometimes suggest directions for finding a defect even before the necessary measurements are taken. 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.
If the SAMSUNG LE40L51BM does not turn on, no control lights on the front panel light up and do not blink, therefore, there is a very high probability of a malfunction of the BN 94-00622J power module. When diagnosing and repairing the BN 94-00622J power supply unit, it is first necessary to check the fuse, and if it breaks, the power switch and rectifier bridge diodes should be checked for avalanche (thermal) breakdown.
It should be remembered that the N-FET keys used in flyback converters rarely fail for no reason to be looked for by checking other elements of the circuit. Often the breakdown is caused by malfunctions of electrolytic capacitors or semiconductor elements in the primary circuit, or by a break in the resistors in the stabilization circuits. The PWM controller chip may also cause a breakdown of the power switch of the converter.
It is somewhat more difficult to look for a malfunction in the converter of the power module with an active KKM (power factor corrector).
If the SAMSUNG LE40L51BM TV does not have an image, but there is sound, the malfunction should be sought in the backlight lamp power converter (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.
In most cases, the diagnosis and repair of the 24V40W2S inverter (HIP0212A) REV4_1 2pcs is difficult due to the organization of protection, which turns it off in emergency cases to avoid fires during short circuits or breaks in high-voltage circuits and when the lamps are depressurized. Often, repairmen block the protection circuits in order to make the necessary measurements at the control points of the inverter to identify the causes of the defect.
All necessary precautions must be observed when disabling the inverter protection during diagnostics and not leaving it disconnected after the repair is completed.
Owners of LE40L51BM TVs are recommended for repair only to qualified specialists with experience! Self-repair attempts without the appropriate knowledge and skills can lead to serious negative consequences!
According to the conditions of compliance with modern world standards for household switching power supplies, the BN94-00622J module provides for the use of a Power Factor Correction unit. The PFC circuit is a flyback converter based on the ICE1PCS02 PWM controller. The reactance of an electrolytic capacitor of a line filter at a frequency of 50-60 Hz is usually not more than 20-30 ohms and its charge directly from the network through open diodes could reach tens of amperes per pulse if no filtering were applied.As a result of the PFC conversion, an increased voltage on the capacitor (about 380V) cannot directly open the rectifier diodes, on the anode of which the voltage will always be slightly less (about 300V) and then its charging current will always be limited by the elements of the PWM controller. As a result, the envelope of the high-frequency pulses of the consumed current will repeat the shape and phase of the input sinusoidal voltage. The presence of an increased voltage (+ 380V) on the mains capacitor indicates the serviceability of the PFC node.
Main features of the SAMSUNG LE40L51BM device:
Installed matrix (LCD-panel) LTA400W2-L01.
The matrix control uses the Timing Controller (T-CON) 400W2C4LTV0.1.
To power the backlight, an inverter 24V40W2S is used, it is controlled by the PWM controller DMB8110D. As power elements of the inverter, keys of type SI4942 are used.
The necessary supply voltages for all nodes of the SAMSUNG LE40L51BM TV are generated by the BN94-00622J power module or its analogs using the STR-W6765, ICE1PCS02 (PFC), VIPer12A (Standby) microcircuits.
MainBoard - the main board (motherboard) is a MAIN_PCB module.
Additional technical information about the panel:
Brand: SAMSUNG
Model: LTA400W2-L01
Type: a-Si TFT-LCD, Panel
Diagonal size: 40 inch
Resolution: 1366x768, WXGA
Display Mode: PVA, Normally Black, Transmissive
Active Area: 885.168x497.664 mm
Surface: Antiglare (Haze 44%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 800: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 10/6 (Tr / Td)
Frequency: 60Hz
Lamp Type: 20 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V