Technical description and composition of the SAMSUNG LE27S71BS TV, panel type and applicable modules. The composition of the modules.SAMSUNG
Model: LE27S71BS
Panel: V270B1-L04 // V270B1-L01 RevC1
T-CON: V320B1-C03 // V270B1-L01 -C
Inverter (backlight): I270B1-12C
PWM Inverter: OZ964GN (20) BA2902F (14)
MOSFET Inverter: AO4614 (8)
Trans Inverter: 4009L 064702 SD-3
Power Supply (PSU): BN96-03058A PSLF181501B
PWM Power: VIPer22A, 4863-2 / G0622, F9222L
MOSFET Power: 2SK3569
MainBoard: BN41-00680D
IC MainBoard: 3F866BXZZ-QZ8B FST 3125 74HC4052D LCX245 M30840SQP DS1834A
Tuner: BN40-00079A TCPW3001PD32S (H)
Technical Specifications LE27S71B
SAMSUNG LE27S71BS
General repair guidelines for TV LCD
Repair of a SAMSUNG LE27S71BS TV is advisable to start with a careful external examination of all its constituent elements, both internal and external. Inspection is also subject to body elements, control buttons, screen, connectors and cords. Sometimes, with some visible changes, you can determine the further direction of the defect search and localization of the malfunction before the start of the acquisition of oscillograms and the necessary measurements at the control points. In most cases, the repairman can guess the causes of the defect and possible consequences by the characteristic signs of typical TV defects, for example, ring cracks formed in the soldering of element outputs, swollen rectifier filter capacitors, charred resistors and other circuit elements.
In cases when the SAMSUNG LE27S71BS TV does not turn on, does not respond to the remote control and buttons, any indicators on the front panel do not light up and do not blink, and when you turn on no sounds or any signs of operability, the BN96-03058A PSLF181501B power supply module is most likely faulty or , which happens much less often - there is no power to the processor on the motherboard. When diagnosing and repairing the BN96-03058A PSLF181501B power supply, the fuse must first be checked, and if it is broken, the 2SK3569 power switch and rectifier bridge diodes should be checked for avalanche (thermal) breakdown.
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 for no reason, which should be sought by checking other elements of the primary circuit - electrolytic capacitors, PWM controller MIP2H2 (7) DLA001D, which can only be checked by replacing , as well as other semiconductor elements (diodes, transistors, zener diodes).
Diagnostics of power modules with a Power Factor Corrector (CMC) is somewhat more complicated and requires a more detailed approach.
If, when you turn on the TV, the image appears and immediately disappears, or is initially absent when turned on, but there are sound and other functions work, there is a high probability of a malfunction of the inverter (power converter for the backlight). In such cases, the lamps, the inverter and the common power module are subject to verification, in which the electrolytic capacitors of the rectifier filter feeding the inverter should be checked.
Diagnostics of the I270B1-12C inverter can be difficult due to the operation of the protection, which is organized by the designers to prevent negative consequences or fires in emergency cases, for example, during short circuits or breaks in the lamp power supply circuit, as well as their possible leakage. To make the necessary measurements at control points or to take the necessary waveforms, repairmen have to block the protection circuits in order to be able to diagnose.
All necessary precautions must be observed when disabling the inverter protection during diagnostics and not leaving it disconnected after the repair is completed.
On the BN41-00680D motherboard, in case of a malfunction, you should first check the performance of all power supply stabilizers of the microcircuits and, if necessary, 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 3F866BXZZ-QZ8B FST 3125 74HC4052D LCX245 M30840SQP DS1834A and other possible faulty components.
Owners and users of the SAMSUNG LE27S71BS 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 BN41-00680D is shown in the figure below:BN41-00680D
BN41-00680D can be used in TVs:
SAMSUNG LE26R71B (Panel T260XW02 V.5), SAMSUNG LE27S71B (Panel V270B1-L01), SAMSUNG LE27S71BS (Panel V270B1-L04), SAMSUNG LE32S71BS LE32S71B (Panel V315B1-L01 Rev.C2 (SAMSUNG LEB) -L01 0T1), SAMSUNG LE32R71B (Panel V320B1-L01 REV.C4), SAMSUNG LE32R72B (Panel T315XW02 V.0).
The appearance of the power supply
Main features of the SAMSUNG LE27S71BS device:
Installed matrix (LCD panel) V270B1-L04 or V270B1-L01 RevC1.
The matrix control uses the Timing Controller (T-CON) V320B1-C03.
To power the backlight, an inverter I270B1-12C is used, it is controlled by the PWM controller OZ964GN (20) BA2902F (14). A transformer 4009L 064702 SD-3 is installed in the inverter converter. As power elements of the inverter, switches of the type AO4614 (8) are used.The necessary supply voltages for all nodes of the SAMSUNG LE27S71BS TV are generated by the BN96-03058A power module or its analogs using VIPer22A, 4863-2 / G0622, F9222L microcircuits and 2SK3569 power switches.
MainBoard - the main board (motherboard) is a BN41-00680D module, using 3F866BXZZ-QZ8B FST 3125 74HC4052D LCX245 M30840SQP DS1834A chips and others.
The tuner BN40-00079A TCPW3001PD32S (H) provides the reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: CMO
Model: V270B1-L04
Type: a-Si TFT-LCD, Panel
Diagonal size: 27.0 inch
Resolution: 1366x768, WXGA
Display Mode: Super MVA, Normally Black, Transmissive
Active Area: 596.259x335.232 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 1200: 1
Display Colors: 16.7M (8-bit), CIE1931 75%
Response Time: 6.5 (G to G)
Frequency: 60Hz
Lamp Type: 12 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V