Technical description and composition of the TOSHIBA 40LV703R TV, type of panel and applicable modules. The composition of the modules.Toshiba
Model: 40LV703R C
Chassis / Version: MST3740EU-T MAIN UNIHAN
Panel: V400H1-L10 REV C1 75018974
T-CON: V460H1-C08 V400H1 V370H3 V315H1, CM501, CM2688A
Inverter (backlight): I400H1-12B T87I111.00 75021313
PWM Inverter: AP11A21SN
MOSFET Inverter: D4184 (3)
Power Supply (PSU): PE-3241-01UN-LF 08032WJKZ REV01 75018813 0433-002H000
PWM Power: A6069H (7), FAN7529B (PFC), L6599D (PWM Resonant)
MOSFET Power: K3569
MainBoard: MST3740EU-T BD REV1.04 75020415 69EB3JM11C06P
IC MainBoard: MST9B884JL-LF-3, 1084 (3), FDS4435BZ (8), IF8AK (6), tun TT2124, DRV602, AIWI TI0AJ
Tuner: TT2124 BTC-102B
Control: Remote: CT90326, IR: 08E1-06R2200
Toshiba
Model: 40LV703R K
Chassis / Version: MST3740EU-T MAIN BD UNIHAN
Panel: LTA400HM02 T03
T-CON: A60MB4C2LV0.2 03392E0D0A2A 013042
Inverter (backlight): LJ97-02752A SSI400_12E Rev0.3 75020794
PWM Inverter: SSI091SN
MOSFET Inverter: 50N04-8P BD498C
Trans Inverter: HS-495 TM 1036 C4
Power Supply (PSU): PE-3241-01UN-LF
PWM Power: A6069H (7), FAN7529B (PFC), L6599D (PWM Resonant)
MOSFET Power: K3569
MainBoard: MST3740EU-T R69EB3JM11C06P 75020415
IC MainBoard: MST9B884JL-LF-3, MX 25L1605DM2I, W9412G6IH-4
Tuner: TT2124
Control: CT-90326
Specifications 40LV703
TOSHIBA 40LV703R
General recommendations for repairing TV LCD
It is advisable to start any repair and diagnostics of the TOSHIBA 40LV703R K TV with a careful external examination of the internal and external elements, including case parts, display, buttons and cables. Many visible signs make it possible to determine the future direction of troubleshooting and localization of the defect. Elements with visible damage, for example, capacitors swelled up after boiling the electrolyte, charred resistors in certain nodes of the circuit, as well as ring cracks in solders will help the master to guess the causes and possible consequences of the malfunction.
Malfunctions of the PE-3241-01UN-LF power module can be expressed in different ways, for example, the TOSHIBA 40LV703R K does not turn on at all and the control lamps on its front panel do not light up and do not blink, there are no signs of operability. If the mains fuse is broken in the power supply, in most cases a breakdown of the K3569 power switch is detected, which can be integrated with the PWM controller, or a separate field-effect transistor can be used. The rectifier bridge diodes and the electrolytic capacitor of the mains rectifier filter should also be checked.
It should be remembered that in the practice of repair, usually the power keys of N-Fet converters do not fail due to their poor quality and, in such cases, it is necessary to look for the cause that led to a malfunction and provoked a breakdown of the key. Most often, the culprits of the accident are dried electrolytic capacitors or dangling resistors in the primary circuit, or the A6069H (7) FAN7529B (8) L6599D (16) PWM controller chip itself may be faulty. It is also necessary to check all the semiconductor elements of the stabilization circuit in the primary and secondary circuits.
When using a power factor correction unit (PFC) in the power modules, troubleshooting becomes somewhat more complicated and requires additional experience and knowledge of their operation.
Sometimes the TOSHIBA 40LV703R K TV does not have an image, but there is sound, or the image appears and immediately disappears. In this case, there is a high probability of a malfunction of the backlight converter, or of the lamps themselves, which can be checked by replacement. In such cases, it is necessary to verify the serviceability of all electrolytic capacitors of the filter according to the power supply of the inverter itself, including in the power supply unit (power supply unit).
When repairing the LJ97-02752A SSI400_12E Rev0.3 75020794 inverter, it is often necessary to disable 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.
If the 69EB3JM11C06P 75020415 motherboard is faulty, first of all it is necessary to check all the linear power regulators of its chips and, if necessary, update the software. Sometimes you can check the health of MB only by replacement. Often, the MB (SSB) card must be replaced in case of complex malfunctions that are difficult to detect. When trying to repair, you should check its elements - MST9B884JL-LF-3 and replace failed chips with new ones.
Once again, remind users! Attempts to independently repair the TOSHIBA 40LV703R K TV without the appropriate qualifications and experience can lead to its complete non-repairability!
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> Toshiba Chassis 32AV703, MST3740EU-T MAIN BD UNIHAN
Service Manual 51 pages on models 19AV703R, 22AV703R, 26AV703R, 32AV703R, 32LV703R, 37LV703R, 40LV703R, 19AV704R, 22AV704R, 26AV704R, 32AV704R, 32LV704R, 37LV704R, 40LV704R
The appearance of the MainBoard MST3740EU-T is shown in the figure below:
MST3740EU-T
MST3740EU-T can be used in TVs:
TOSHIBA 26AV703R (Panel V260B3-L04 RevC1), TOSHIBA 32AV703R C (Panel V315B5-L12 75018968), TOSHIBA 32AV703R K (Panel LTA320AP08 75016146 ), TOSHIBA 32AV704R (Panel V315B5-L12 Rev01 75018968), TOSHIBA 32LV703R A (Panel T315HW04 V.4 (12v) 75018019), TOSHIBA 32LV703R K (Panel LTA320HA04 T01 75016399 (12v)), TOSHIBA 40LV703R C (Panel V400H1-L10 REV C1 75018974), TOSHIBA 40LV703R K (Panel LTA400HM02 T03).
PSU Advanced
The 40LV703R model uses a PE-3241-01UN-LF power supply unit using the PFC (Power Factor Correction) node - an active filter of the highest harmonics of the current consumption. In fact, this is a boost converter based on the FAN7529B PWM controller, which eliminates the charge current of the electrolytic capacitor of the rectifier filter directly from the network through open diodes when its charging current is determined by its reactance.
As a result of the operation of the converter, the envelope of the high-frequency pulses of the input current of the converter will repeat the shape and phase of the input voltage. The health of the PFC node can be indirectly judged by the presence of an increased constant voltage (about + 380V) on the capacitor of the rectifier network in operating mode.
Key Features of the TOSHIBA 40LV703R:
Installed matrix (LCD-panel) LTA400HM02 T03.
The matrix control uses the Timing Controller (T-CON) A60MB4C2LV0.2.
To power the backlight, an LJ97-02752A inverter is used, it is controlled by the SSI091SN PWM controller. The transformer HS-495 TM 1036 C4 is installed in the inverter converter. As power elements of the inverter, keys of the type 50N04-8P BD498C are used.
The necessary supply voltages for all nodes of the TOSHIBA 40LV703R TV are generated by the PE-3241-01UN-LF power module or its analogs using A6069H (7), FAN7529B (PFC), L6599D (PWM Resonant) microcircuits and K3569 type power switches.
MainBoard - the main board (motherboard) is an MST3740EU-T module, using microchips MST9B884JL-LF-3, MX 25L1605DM2I, W9412G6IH-4 and others.
The TT2124 tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: SAMSUNG
Model: LTA400HM02
Type: a-Si TFT-LCD, Panel
Diagonal size: 40 inch
Resolution: 1920x1080, FHD
Display Mode: S-PVA, Normally Black, Transmissive
Active Area: 885.6x498.15 mm
Surface: Antiglare (Haze 4.5%), Hard coating (3H)
Brightness: 450 cd / m²
Contrast Ratio: 4500: 1
Display Colors: 1.07B (8-bit + Hi-FRC), CIE1931 72%
Response Time: 8 (G to G)
Frequency: 60Hz
Lamp Type: 12 pcs CCFL Embedded (Inverter)
Signal Interface: LVDS (2 ch, 10-bit), 51 pins
Voltage: 12.0V