Technical description and composition of the DEXP 40A7100 TV, type of panel and applicable modules. The composition of the modules.DEXP LED
Model: 40A7100
Chassis / Version: MSD309B-T9B
Panel: V400HJ6-ME2 REV.C1 // C400F13-E2-C (G2)
LED backlight: V400HJ6-ME2-TREM1 - 6202B0005V000
LED driver (backlight): integrated into PSU
PWM LED driver: AP3041
Power Supply (PSU): K-PL-0A1 LYP03008A0
PWM Power: OB5269CP
MainBoard: MSD309B-T9B 4704-309BT9-A3235K01 A3
IC MainBoard: 25Q32BV
Specifications 40A7100
DEXP 40A7100
General repair guidelines for TV LCD LED
Possible malfunctions
- DEXP 40A7100 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 such cases, the fault should be sought first in the K-PL-0A1 power supply module. It is necessary to measure its output voltages, and in case of their absence (full or partial), it is necessary to check the serviceability of the power switches of the converters and rectifier diodes for the presence of a possible short circuit.
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) OB5269CP, in the absence of external damage and short circuit between the terminals, are checked by replacing with obviously good ones.
- There is no image, but there is sound and reaction to commands from the remote control. Or the image appears immediately after turning on and disappears.
In such cases, the most likely malfunction of the LED backlight elements. 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, does not respond to the remote control. The indicator blinks or signals standby mode.
Repair or diagnostics of the motherboard MSD309B-T9B should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). Complex repair of MB (SSB) is possible only in the conditions of a service center with the necessary equipment. Testing or replacing elements 25Q32BV requires the necessary training and professional skills to repair modules at the component level. Problems associated with the use of BGA soldering technologies can sometimes be diagnosed by warming up.
Attention TV owners! Attempts at self-repair of the DEXP 40A7100 are not recommended by the manufacturer and can lead to serious negative consequences!
FIRMWARE FOR SPI FLASH -----------> DEXP 40A7100, Main: MSD309B-T9B 4704-309BT9-A3235K01 A3, Panel: V400HJ6-ME2 REV.C1
FIRMWARE FOR SPI FLASH -----------> DEXP 40A7100, Main: MSD309B-T9B 4704-309BT9-A3235K01 A3, Panel: C400F13-E2-C(G2)
The appearance of the MainBoard MSD309B-T9B is shown in the figure below:MSD309B-T9B
The appearance of the power supply
Main features of the DEXP 40A7100 device:
Installed matrix (LED-panel) V400HJ6-ME2 REV.C1 or C400F13-E2-C (G2).
To power the backlight LEDs, a converter is used, combined with the power supply, controlled by the AP3041 PWM controller.
The necessary supply voltages for all nodes of the DEXP 40A7100 TV are generated by the K-PL-0A1 power module or its analogs using OB5269CP microcircuits.
MainBoard - the main board (motherboard) is an MSD309B-T9B module, using 25Q32BV chips and others.
Additional technical information about the panel:
Brand: INNOLUX
Model: V400HJ6-ME2
Type: a-Si TFT-LCD, Panel
Diagonal size: 40 inch
Resolution: 1920x1080, FHD
Display Mode: Super MVA, Normally Black, Transmissive
Active Area: 878.112x485.352 mm
Surface: Antiglare (Haze 1%), Hard coating (3H)
Brightness: 300 cd / m²
Contrast Ratio: 5000: 1
Display Colors: 16.7M (8-bit), CIE1931 72%
Response Time: 8.5 (G to G)
Frequency: 60Hz
Lamp Type: WLED Without Driver
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V
DEXP 40A7100 TV with V400HJ6-ME2 LCD, 40 "(102 cm) diagonal, 16: 9 format. The required screen brightness of 300 cd / m² is provided by LED backlighting. Dynamic contrast ratio of 5000: 1 is achieved by special control of the LEDs depending on from the illuminated areas in the plot. This model uses a panel with an end arrangement of backlight LEDs - Edge LED. The TV features include viewing programs and movies in high quality HD at a resolution of 1920x1080 pixels in a graphical layout with andartu 1080p (Full HD). The input high-frequency or video signal is decoded in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3 , 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 x3, component, SCART, VGA, HDMI x3, USB x2. 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, 1280x1024, 1360x768, 1920x1080. A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Overall dimensions: without stand 904x514x51 mm.
Mass of the TV: 11.5 kg.
Attention! The V400HJ6-ME2 REV.C1 panel of the DEXP 40A7100 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.