Technical description and composition of the DEXP H39D7000Q TV, panel type and applicable modules. The composition of the modules.DEXP LED
Model: H39D7000Q
Chassis / Version: CV512H-U42
Panel: LC390TA2A
T-CON: PANDA385L RUNTKD070ZZPN
LED driver (backlight): integrated into MainBoard
PWM LED driver: PWM 8pin
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MainBoard: CV512H-U42
IC MainBoard: 25Q64
Tuner: CDT-9NT372
Technical Specifications H39D7000Q
DEXP H39D7000Q
General repair guidelines for TV LCD LED
Possible malfunctions
- The DEXP H39D7000Q TV does not turn on at all. There is no reaction to the remote control and control buttons from the front panel. Indicator lights do not light or flash.
In such cases, the main power source, the AC / DC voltage converter, which is combined with the MainBoard CV512H-U42, may turn out to be faulty. It is then necessary to measure its output voltages and, if they are absent, it is necessary to check the power switches and rectifier diodes of the converters for a short-circuit probability.
In case of diode breakdowns in the secondary circuits, the converter can operate in emergency short-circuit mode without output voltages, and during short circuit in the power elements of the primary circuit, the mains fuse and / or current sensor at the source of the key 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. 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 is responding to the remote control. Or immediately after turning on for a second, the image may appear and immediately disappear.
In such cases, the most likely malfunction of the LED backlight elements. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
To check the LED strips, to open all the transitions of the LEDs, several tens of volts or more are needed, it is best to use a current source for such purposes. The breakage of several PN junctions connected in series cannot be detected with a multimeter or tester. In such cases, it is necessary to open the panel and check each LED. If your multimeter cannot open the LED transitions in forward bias, you can sometimes detect the presence of a PN junction of the protective zener diode by connecting the probes in the opposite direction. If the zener diode is broken or broken in short-circuit, then the LED is faulty and needs to be replaced.
- The TV does not enter the operating mode, does not respond to the remote control. The indicator on the front panel lights constantly or blinks.
Repair or diagnostics of the CV512H-U42 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). Board repair and replacement of W24Q64 microcircuits are carried out with the necessary equipment, and the corresponding element base. Faults associated with the application of BGA processor soldering technologies can be localized by the heating method.
If the TV works normally from external devices, but does not tune to television channels, the tuner CDT-9NT372 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.
Attention! For users and owners of H39D7000Q TVs who do not have the appropriate qualifications, knowledge and experience, we strongly recommend against attempting self-repair in order to avoid negative consequences that could lead to complete non-repairability of the device.
FIRMWARE FOR SPI FLASH -----------> DEXP H39D7000Q, Main: CV512H-U42, Panel: LC390TA2A
The appearance of the MainBoard CV512H-U42 is shown in the figure below:Cultraview CV512H-U42
CV512H-U42 can be used in TVs:
DEXP H39D7000Q (Panel LC390TA2A), SUPRA STV-LC32LT0010W (Panel KM0320LDRH0037).
Main features of the DEXP H39D7000Q device:
Installed matrix (LED-panel) LC390TA2A.
The matrix control uses the PANDA385L Timing Controller (T-CON).
To power the backlight LEDs, a converter is used, combined with the main board CV512H-U42, controlled by a PWM 8pin PWM controller.
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.
MainBoard - the main board (motherboard) is a CV512H-U42 module, using 25Q64 chips and others.
Tuner CDT-9NT372 provides the reception of television programs and tuning to channels.
DEXP H39D7000Q TV with an LCD display LC390TA2A, diagonal size 38.5 "(98 cm) 16: 9 format. The required brightness of the screen 300 cd / m² is provided by LED backlight LED. Contrast - the ratio of maximum brightness to minimum is 3000: 1. In LCD - panels use direct LED backlighting - Direct LED. You can watch programs and movies and images in high quality HD at a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready). Supported media file formats: MP3, WMA, MPEG4, HEVC (H.265), Xvid, DivX, MKV, JPEG.
The power of the sound system 20 W (2x10 W) provides 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, component, VGA, HDMI x3, MHL, USB x2. An output for connecting headphones is provided. The digital tuner is capable of receiving television channels in DVB-T MPEG4, DVB-C, DVB-T2 standards.
The power consumed by the TV working in the network mode is 75 watts.
Overall dimensions: with stand 885x556x208 mm, without stand 885x509x66 mm.
TV Weight: with stand: 6 kg, without stand: 5.9 kg.
Attention! The LC390TA2A panel of a DEXP H39D7000Q 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.
