Technical description and composition of the DNS M39DAC TV, panel type and modules used. The composition of the modules.DNS LED
Model: M39DAC
Chassis / Version: T.MSD309.B21B
Panel: V390HJ1-L02
T-CON: V390HJ1-XC01 + V390HJ1-XR01
LED driver (backlight): I390HJ1-08A
Power Supply (PSU): LK-PI400112A CQC04001011196
MainBoard: T.MSD309.B21B
IC MainBoard: Spi Flash: 25Q3, Audio: TPA3124D2
Tuner: NoName
M39DAC Specifications
DNS M39DAC
General recommendations for TV LCD LED repair
Possible manifestations of defects
- DNS M39DAC TV does not turn on, does not respond to the remote control and control panel buttons, does not light up or blink indicators.
In some of these cases, the main switching power supply, the LK-PI400112A module, turns out to be faulty. It is necessary to make sure that its output voltages are present and, if they are completely absent, check the power switches and rectifier diodes for a possible short circuit.
In case of breakdowns in the secondary circuits, the converter, as a rule, can operate in an emergency mode in a short-circuit mode, and in case of a short circuit in the power elements of the primary circuit, the mains fuse is usually cut off.
Breakdown of power switches (MosFet) in switching sources is sometimes caused by malfunctions of other circuit elements, for example, in the circuits supplying the PWM controller, frequency setting or damper, as well as in the circuits of Negative Feedback (OOS) stabilization. PWM controllers (PWM), if they do not have visible damage to the case and an outright short circuit between the terminals, are usually checked by replacement.
- There is no image, there is sound, it reacts to the remote control. Or the image may appear for a second when turned on and immediately disappear.
The most likely problem in these cases is a malfunction of the LED backlight. The reason for this may be an open circuit in the LED circuit, or a problem in stabilizing their power supply.
It is impossible to check the LED bars for a break 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 is required, and ideally a current source. Having disassembled the panel, it is necessary to check each LED separately. Chinese multimeters tend to light one 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 an indicator of serviceability. In faulty LEDs, the zener diode will either be cut off or broken through in the K / Z.
- The indicator on the front panel blinks, the TV does not turn on in operating mode, does not respond to the remote control.
Repair or diagnostics of the T.MSD309.B21B motherboard should begin with checking the stabilizers and power converters necessary to power the microcircuits and matrix. If necessary, you should update or replace the software (software). Repair of the board and replacement of Spi Flash: 25Q3, Audio: TPA3124D2 microcircuits are performed with the necessary equipment and the corresponding element base. Malfunctions associated with the use of BGA soldering technologies can be localized by the warm-up method.
Users and owners of TVs should remember that attempts to repair the DNS M39DAC TV on their own without the appropriate qualifications and the necessary experience can lead to serious negative consequences!
DOWNLOAD FIRMWARE FOR SPI FLASH -----------> DNS M39DAC, Main: T.MSD309.B21B, Panel: V390HJ1-L02
The appearance of the MainBoard T.MSD309.B21B is shown in the figure below:T.MSD309.B21B
External view of the power supply
Main features of the DNS M39DAC device:
Installed matrix (LED panel) V390HJ1-L02.
Matrix control uses Timing Controller (T-CON) V390HJ1-XC01.
The LED driver I390HJ1-08A is used to power the backlight LEDs.
The formation of the necessary supply voltages for all nodes of the DNS M39DAC TV is carried out by the LK-PI400112A power module, or its analogs.
MainBoard - the main board (motherboard) is a T.MSD309.B21B module, using Spi Flash: 25Q3, Audio: TPA3124D2 and others.
Tuner NoName provides reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: CHIMEI INNOLUX
Model: V390HJ1-L02
Type: a-Si TFT-LCD, Panel
Diagonal size: 39 inch
Resolution: 1920x1080, FHD
Display Mode: Super MVA, Normally Black, Transmissive
Active Area: 853.92x480.33 mm
Surface: Antiglare (Haze 3.5%), Hard coating (3H)
Brightness: 350 cd / m²
Contrast Ratio: 3000: 1
Display Colors: 16.7M (8-bit), CIE1931 68%
Response Time: 8.5 (G to G)
Frequency: 60Hz
Lamp Type: 8 pcs CCFL Embedded (Balance board)
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V
DNS M39DAC TV with LCD V390HJ1-L02, 39 "(99 cm) diagonal in 16: 9 format. 400 cd / m² screen brightness is provided by CCFL (EEFL) fluorescent lamps. Contrast - ratio of maximum brightness to minimum brightness is 3000 : 1. Dynamic contrast ratio of 100,000: 1 is achieved by special control of the backlight.
The V390HJ1-L02 matrix and the MainBoard T.MSD309.B21B software provide viewing of broadcasts and movies in high quality HD at a resolution of 1920x1080 pixels in graphics decomposition at 1080p (Full HD). The input high-frequency or video signal is decoded in analog systems PAL, SECAM, NTSC. Graphic processing and formation of a digital signal occurs in the 480i, 480p, 576i, 576p, 720p, 1080i standards. Supported media file formats: MP3, MPEG4, MKV, JPEG.
Speaker power 24 W (2x12 W) is provided by two speakers. The NICAM STEREO audio processing system is used.
External interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, audio x2, component, SCART, VGA, HDMI x3, USB. A headphone output is provided. To connect a computer or laptop to this TV model, use the VGA (D-Sub 15) connector on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768, 1280x1024, 1360x768, 1920x1080. The digital tuner is capable of receiving TV channels in DVB-T standards.
The power consumed by the TV operating in mains mode is 160 W. Power supply LK-PI400112A.
Overall dimensions: 921x632x255 mm.
TV weight: 12.2 kg.
Attention! The V390HJ1-L02 panel of the DNS M39DAC LCD TV is the most expensive component.
Avoid hitting the glass and putting pressure on the screen surface to avoid irreversible damage to the LCD panel!