Technical description and composition of the BBK LT3218SU TV, panel type and applicable modules. The composition of the modules.BBK
Model: LT3218SU
Panel: LTA320AP02 S07
Inverter (backlight): SSI320_4UA01
PWM Inverter: OZ9966SN (24), A393F (8)
MOSFET Inverter: KMB054N40DB, STU432S
Trans Inverter: LT-U3208 T 10 13 E Y
Power Supply (PSU): HLP-23A02 - RSAG7.820.1377 / ROH VER.B // H-120822 POWER BOARD // -
PWM Power: 1653A (PFC), NCP1217 (8), 1207A (8)
MOSFET Power: 10N60C, 3N80C, 20N60C
MainBoard: RSAG7.820.1637 / ROH VER.E
IC MainBoard: R2A15108 FP, TDA9886TS, 74HC4052
Tuner: TDQ-6F / W126 LC320V88
BBK
Model: LT3218SU
Panel: LTA320AP02
Inverter (backlight): SSI320-4UA01
PWM Inverter: OZ9966SN (24pin), A393F
MOSFET Inverter: KMB054N40DB, STU432S
Trans Inverter: LT-U3208
Power Supply (PSU): HLP-23A02 - RSAG7.820.1377 / ROH LCD32V88 / 120822C
PWM Power: NCP1653AD (PFC), NCP1217AD65, NCP1207D
MOSFET Power: FQPF10N60C, FQPF3N80C, 20N60
MainBoard: RSAG7.820.1637 LCD32V88 / 121490
IC MainBoard: CPU: MT8222, Flash: MX25L3206E, Eeprom: 24C16, R2A15108FP
Tuner: TDQ-6FT / W126H
Technical Specifications LT3218SU
BBK LT3218SU
General recommendations for repairing TV LCD
Possible malfunctions
- The BBK LT3218SU TV does not turn on and does not show any signs of operability at all. There is no reaction to either the remote control or the front panel control buttons.
Most often, with such manifestations, the main power module HLP-23A02 is found to be faulty. It is necessary to measure its secondary output voltages, and in case of their absence, check the serviceability of the power switches (FQPF10N60C, FQPF3N80C, 20N60) of the converters and rectifier diodes for a 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.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can put it out of operation in key mode or provoke an excess of the maximum current or voltage. It can be supply, damper circuits, or elements of OOS (negative feedback) stabilization. The reason for the breakdown of the power key can be PWM (PWM) NCP1653AD (PFC), NCP1217AD65, NCP1207D. It is checked only by replacement with a known good one.
- There is no image, but there is sound and reaction to the remote control. Or for a second, the image may appear immediately after switching on.
These manifestations can be triggered by the power module, or by inverter defects, as well as by the 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 circuit should be restored immediately after the repair is completed.
- The indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the RSAG7.820.1637 motherboard should begin by checking the stabilizers and power converters needed to power the microcircuits and matrix. If necessary, update or replace the software (software). In cases of attempts to repair the MB (SSB) board, it is necessary to check the health of its elements - Cpu: MT8222, Flash: MX25L3206E, Eeprom: 24C16, R2A15108FP which may require replacement with new ones. If a BGA processor is installed, there is a possibility of a violation of the soldering of the contacts of its conclusions with the board (it is diagnosed by heating).
If the TV works normally from external devices, but does not tune into television channels, the TDQ-6FT / W126H tuner may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding conclusions. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus. Sometimes the cause of the inoperability of the tuner may be a software failure.
For LT3218SU TV owners, we recommend that you contact qualified personnel with the necessary work experience for repairs! Self-repair attempts without the appropriate knowledge and skills can lead to irreversible negative consequences!
The appearance of the MainBoard RSAG7.820.1637 is shown in the figure below:RSAG7.820.1637
RSAG7.820.1637 can be used in TVs:
BBK LT3218SU (Panel LTA320AP02 S07), BBK LT3218SU (Panel LTA320AP02), ROLSEN RL-32A03105U (Panel LTA320AP02), ROLSEN RL-32A09105F (Panel LC320WUN (SA)(B4)), ROLSEN RL-32A09105U (Panel LTA320AP05).
PSU Advanced
The HLP-23A02 power module is installed in the LT3218SU TV using the PFC (Power Factor Correction) circuitry acting as an active filter to eliminate the higher harmonic components of the current consumption. The boost converter based on the NCP1653AD PWM controller does not allow the input rectifier filter's electrolytic capacitor to be connected directly to the network directly through open diodes when the charge current determines its reactance (about 15-30 ohms at a frequency of 50 Hz). As a result of the conversion, the charging current of the capacitor will be determined in such a way that the envelope of the high-frequency pulses of the input current will repeat the phase and shape of the sine wave of the input voltage. The health check of the PFC unit is carried out by measuring the DC voltage on the capacitor of the rectifier network. In operating mode, it should be around 380V, in standby approximately 300V.
The appearance of the power supply
Main features of the BBK LT3218SU device:
Installed matrix (LCD-panel) LTA320AP02.
The SSI320-4UA01 inverter is used to power the backlight, controlled by the OZ9966SN PWM controller (24pin), A393F. A transformer LT-U3208 is installed in the inverter converter. As power elements of the inverter, keys of the type KMB054N40DB, STU432S are used.
The necessary supply voltages for all nodes of the BBK LT3218SU TV are generated by the HLP-23A02 power module or its analogs using NCP1653AD (PFC), NCP1217AD65, NCP1207D microcircuits and power switches of the type FQPF10N60C, FQPF3N80C, 20N60.
MainBoard - the main board (motherboard) is an RSAG7.820.1637 module, using Cpu chips: MT8222, Flash: MX25L3206E, Eeprom: 24C16, R2A15108FP and others.
The TDQ-6FT / W126H tuner provides television reception and channel tuning.
Additional technical information about the panel:
Brand: SAMSUNG
Model: LTA320AP02
Type: a-Si TFT-LCD, Panel
Diagonal size: 31.5 inch
Resolution: 1366x768, WXGA
Display Mode: PVA, Normally Black, Transmissive
Active Area: 697.68x392.26 mm
Surface: Antiglare (Haze 7%), Hard coating (3H)
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: 4 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 12.0V
Brand: BBK, Model: LT3218SU.
Briefly from the TV: LCD, 720p HD, 32 "(81 cm) diagonal, HDMI: 3, USB: 2, PIP.
The composition uses MainBoard RSAG7.820.1637 and an LCD panel (matrix) LTA320AP02.
Power Supply Unit (PSU) HLP-23A02 - RSAG7.820.1377 / ROHC Power Supply.
BBK LT3218SU LCD TV with LTA320AP02 LCD display, 32 "(81 cm) diagonal size in 16: 9 format. 450 cd / m² screen brightness is provided by CCFL (EEFL) fluorescent lamps. Dynamic contrast ratio 4000: 1 is achieved by special operation control It is possible to view images in high quality HD with a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready). The input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation takes place in standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, MPEG4, JPEG.
The power of the sound system 12 W (6x2 W) provide two speakers. It uses the NICAM stereo signal processing system and Sound Surround.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV x2, audio x4, S-Video, component, SCART x2, RGB, VGA, HDMI x3, USB x2. An output for connecting headphones is provided. To connect a computer or laptop to this TV model, a VGA (D-Sub 15) connector is used on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768.
The power consumed by the TV in the operating mode from the network is 140 watts.
Overall dimensions: With stand 788x561x252 mm, Without stand 788x511x101 mm.
Attention! The BBK LT3218SU LCD TV panel LTA320AP02 is the most expensive component of it.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!
