Technical description and composition of the DEXP H32D7200C TV, type of panel and applicable modules. The composition of the modules.DEXP LED
Model: H32D7200C
Chassis / Version: HLS80JS
Panel: C320X18-E5C-H (G11)
LED backlight: LB-C320X18-E5C-H-G01-XRD2
LED driver (backlight): integrated into MainBoard
MOSFET LED driver: TO-252
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MOSFET Power: TO-252
MainBoard: JUC7.820.00208835 HLS80JS
IC MainBoard: CPU: MSD3663LSA 005N, SPI Flash: GD25Q64, Audio: OB6228UP
Tuner: DVB + SAT
Technical Specifications H32D7200C
DEXP H32D7200C
General repair guidelines for TV LCD LED
Possible manifestations of defects
- DEXP H32D7200C does not turn on, does not respond to buttons and remote control, indicators on the front panel do not light up and do not blink.
In such cases, the common power source, the AC / DC converter of the mains voltage, which is combined with the elements of the JUC7.820.00208835 main board, is often faulty. 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 power switches (TO-252) of 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) PWM SOT23-6, 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 the remote control. Or for a second, the image may appear immediately after switching on.
As a rule, in such cases there is no display backlight. Often the cause of the malfunction is the lack of current in the LED circuit, for example, an open or short circuit, or a violation of the contact connections of the connectors.
It is impossible to detect a break in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and to open their transitions, a voltage of several tens of volts is required. Ideally, a current source is suitable for such purposes. You can open the panel and check each LED separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect the probes in the forward direction to it (red probe to the anode, black to the cathode). In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of health. In the event of a LED malfunction, its 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 JUC7.820.00208835 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). When repairing an MB board, you need to check its CPU components: MSD3663LSA 005N, SPI Flash: GD25Q64, Audio: OB6228UP. Defective items should be replaced. If chips with BGA soldering technology are used, a problem in its implementation is detected by the local heating of the chip.
If you suspect a malfunction of the DVB + SAT tuner, first of all, you need to verify the correctness of the software, as well as the presence of the necessary voltage levels and pulses of data exchange with the processor via the I2C bus at the corresponding tuner pins.
Once again, we remind TV users: you should not make attempts to repair it yourself without the appropriate knowledge, experience and the necessary qualifications! Entrust repair to professionals with sufficient experience in the field of repair of electronic equipment.
The appearance of the MainBoard JUC7.820.00208835 is shown in the figure below:JUC7.820.00208835
Main features of the DEXP H32D7200C device:
Installed matrix (LED-panel) C320X18-E5C-H (G11).
To power the backlight LEDs, a converter is used, combined with the main board JUC7.820.00208835. 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-252 type power switches.
MainBoard - the main board (motherboard) is a JUC7.820.00208835 module, using CPU chips: MSD3663LSA 005N, SPI Flash: GD25Q64, Audio: OB6228UP and others.
The DVB + SAT tuner provides television reception and channel tuning.
DEXP H32D7200C TV with C320X18-E5C-H LCD, 32 "(81 cm) diagonal size of 16: 9 format. The required screen brightness of 200 cd / m² is provided by LED backlighting. Contrast - the ratio of maximum brightness to minimum is 3000: 1. The LCD panel uses direct pixel illumination with rear LEDs - Direct LED. You can watch broadcasts and movies and images in high quality HD at a resolution of 1366x768 pixels in the standard graphic decomposition 720p (HD Ready). Supported media file formats: MP3, MPEG4, HEVC (H. 265), JPEG.
The power of the sound system 10 W (2x5 W) provide 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, HDMI x2, USB. 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 55 watts.
Overall dimensions: with stand 730x478x180 mm, without stand 730x435x85 mm.
TV Weight: with stand: 4 kg, without stand: 3.95 kg.
Attention! The C320X18-E5C-H (G11) panel of a DEXP H32D7200C 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.
