Technical description and composition of the DEXP H32D7000M TV, type of panel and applicable modules. The composition of the modules.DEXP LED
Model: H32D7000M
Chassis / Version: LDD.M3463.E
Panel: HV320WHB-N8D
T-CON: T-CON: HV320WHB-N8D; KL5TW151, G5562A, I7991
LED driver (backlight): integrated into MainBoard
PWM LED driver: OB3350CP
MOSFET LED driver: SM1A23N
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MOSFET Power: MMF60R580P
MainBoard: LDD.M3463.E
IC MainBoard: SPI Flash: GD25Q64, AUDIO: CS3818EO
Tuner: NoName
Technical Specifications H32D7000M
DEXP H32D7000M
General repair guidelines for TV LCD LED
Possible malfunctions
- The DEXP H32D7000M TV does not turn on at all. The control lights do not light or flash. The TV on the remote control and the control panel buttons do not respond.
In such cases, the main power source - the AC / DC voltage converter, which is combined with the MainBoard LDD.M3463.E board, may turn out to be faulty. Then we recommend that you measure its output voltages and, if they are absent, you should check the health of the power switches (MMF60R580P) and the rectifier diodes of the converters for possible short-circuit.
In case of breakdowns of semiconductors in the secondary circuits, the converter can usually work abnormally in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse 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, there is sound, it responds to the remote control. Or the image may appear for a second when turned on and immediately disappears.
In some of these cases, the malfunction is caused by a lack of backlighting on the display. 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 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 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 LDD.M3463.E motherboard should be started by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). If it is not possible to replace the MB board (SSB), you need to check the health of its elements - SPI Flash: GD25Q64, AUDIO: CS3818EO. Defective components should be replaced.
Before replacing the NoName tuner, if there is no tuning to the channels, you must first check the software and the supply voltage at its terminals. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus
Owners and users of the DEXP H32D7000M TV should remember that self-repair without special knowledge, skills and qualifications can be fraught with negative consequences that can lead to complete non-repairability of the device!
FIRMWARE FOR SPI FLASH -----------> DEXP H32D7000M, Main: LDD.M3463.E, Panel: HV320WHB-N8D
The appearance of MainBoard LDD.M3463.E is shown in the figure below:LDD.M3463.E
Main features of the DEXP H32D7000M device:
Installed matrix (LED-panel) HV320WHB-N8D.
The matrix control uses the Timing Controller (T-CON) T-CON: HV320WHB-N8D ;.
To power the backlight LEDs, a converter is used, combined with the main board LDD.M3463.E, controlled by the OB3350CP PWM controller. As power elements of the LED driver, keys of the type SM1A23N 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 power switches of the MMF60R580P type.
MainBoard - the main board (motherboard) is an LDD.M3463.E module, using SPI Flash chips: GD25Q64, AUDIO: CS3818EO and others.
The NoName tuner provides television reception and channel tuning.
DEXP H32D7000M TV with HV320WHB-N8D LCD, 31.5 "(80 cm) diagonal size of 16: 9 format. The required screen brightness of 250 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 of graphic decomposition 720p (HD Ready). Supported media file formats: MP3, MPEG4, MKV, JP EG.
The power of the sound system 20 W (2x10 W) provides two speakers. The audio processing system NICAM STEREO is used.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, component, VGA, HDMI x3, USB. 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 65 watts.
Overall dimensions: with stand 732x478x208 mm, without stand 732x434x85 mm.
TV Weight: with stand: 4 kg, without stand: 3.91 kg.
Attention! The HV320WHB-N8D panel of a DEXP H32D7000M 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.
