Technical description and composition of the TCL LED40D2900 TV, panel type and applicable modules. The composition of the modules.TCL LED
Model: LED40D2900 LED40D2900S
Chassis / Version: TP.S512.PB775
Panel: LVF400SSOT
T-CON: 15Y_40GF11BMB7S4LV0.1; LTF64B2, RT6929, RT6936
LED driver (backlight): integrated into MainBoard
PWM LED driver: GB98AERN
MOSFET LED driver: TO-252
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MOSFET Power: TO-220
MainBoard: TP.S512.PB775 / SI512SP1
IC MainBoard: TPA3110LD2, 25Q64CSIG, GB98AERN
Tuner: NoName R840 (Rafael Micro）
Technical Specifications LED40D2900S
TCL LED40D2900
General repair guidelines for TV LCD LED
Possible malfunctions
- TCL LED40D2900 does not turn on and does not show any signs of performance at all. Does not blink indicators and does not respond to control buttons.
In this case, first of all, it is necessary to check the operability of the main power source - the AC / DC network voltage converter, all of whose elements are located on the MainBoard TP.S512.PB775 board. It is necessary to measure its output voltages and, if they are absent, to check the short circuit probability in the converters power switches and rectifier diodes.
In case of any breakdowns in the secondary circuits, the converter can operate in emergency short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse or the current sensor at the source of the key more often 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. These can be circuits supplying the PWM controller, damping or frequency-setting circuits, or elements of OOS (negative feedback) in the stabilization circuit. PWM controllers (PWM), in the absence of external damage and short circuit between the terminals, are checked by replacing with obviously good ones.
- There is no image, there is sound, it responds to the remote control. Or the image may appear for a second when turned on and immediately disappears.
As a rule, in such cases there is no display backlight. The reason can be both in the power supply of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
It is impossible to check the LED line for breaks without disassembling the panel with a multimeter or tester. For these purposes, it is necessary to open all series-connected PN junctions and a voltage of the order of tens of volts will be required, and ideally, a current source. Having disassembled the panel, it is necessary to check each LED separately. Chinese multimeters, as a rule, light up a single 3-volt LED in the forward direction. In the case of using dual 6-volt LEDs, the PN junction of its protective zener diode can serve as a health indicator. In faulty LEDs, the zener diode will either be cut off or broken into short-circuit.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the TP.S512.PB775 motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). 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 - TPA3110LD2, 25Q64CSIG, GB98AERN and replace failed chips with new ones. Some malfunctions may be due to the use of BGA soldering technologies in modern Main Board technologies. Typically, such defects are detected by local heating of the chip.
Attention TV owners! Attempts at self-repair of TCL LED40D2900 are not recommended by the manufacturer and can lead to serious negative consequences!You can reduce the backlight current in LED drivers with the GB98AERN controller by proportionally increasing the total resistance of the resistors from pin 6 (ISET) to the chassis.
The appearance of MainBoard TP.S512.PB775 is shown in the figure below:TP.S512.PB775
TP.S512.PB775 can be used in TVs:
TCL LED40D2900 (Panel LVF400SSOT), TCL LED32D2900 LED32D2900S (Panel ST3151A05-8 Ver.2.4).
Main features of the TCL LED40D2900 device:
Installed matrix (LED-panel) LVF400SSOT.
The matrix control uses the Timing Controller (T-CON) 15Y_40GF11BMB7S4LV0.1 ;.
To power the backlight LEDs, a converter is used, combined with the TP.S512.PB775 main board, controlled by the GB98AERN PWM controller. As power elements of the LED driver, keys of the TO-252 type are used.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using PWM SOT23-6 microcircuits and TO-220 type power switches.
MainBoard - the main board (motherboard) is a TP.S512.PB775 module, using TPA3110LD2, 25Q64CSIG, GB98AERN and other chips.
The tuner NoName R840 (Rafael Micro) provides the reception of television programs and tuning to channels.
TCL LED40D2900S TV with LSC400HN02-802 LCD, 40 "(102 cm) diagonal, 16: 9 format. The LED screen technology is implemented in the technology of making this TV model. The design and technical capabilities of the TV include watching programs and movies in high quality HD at a resolution of 1920x1080 pixels in graphic decomposition according to the standard 1080p (Full HD). Supported media file formats: MP3, MPEG4, MKV, JPEG.
The power of the sound speaker system 16 W (2x8 W) is provided by two speakers. It uses a 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, audio x2, component, VGA, HDMI x2, USB x2. An output for connecting headphones is provided.
The digital tuner is capable of receiving television channels in the standards DVB-T MPEG4, DVB-C, DVB-T2, DVB-S2.
Overall dimensions: with stand 922x592x193 mm, without stand 922x537x73 mm.
TV Weight: with stand: 6.6 kg, without stand: 6.5 kg.
Attention! The LSC400HN02-802 panel of the TCL LED40D2900S LED TV is an expensive and unreliable element.
Avoid any impact on the glass and pressure on the surface of the screen to avoid damage to the LED panel!
It is also unsafe to get liquid on the screen. Sometimes one drop is enough if it flows down the glass onto the cables so that the TV becomes unrepairable.