Thursday 9 April 2020

REPAIR / SERVICING TV AIWA 32LE7020

Technical description and composition of the TV AIWA 32LE7020, type of panel and applicable modules. The composition of the modules.
AIWA LED
Model: 32LE7020
Chassis / Version: V1R07
Panel: LC320DXJ (SH) (A2)
LED driver (backlight): integrated into MainBoard
PWM LED driver: MP3398A
MOSFET LED driver: D4286
Power Supply (PSU): integrated into MainBoard
PWM Power: LNK6778K
MainBoard: 5800-A6M31G-0P10 VER: 00.0
IC MainBoard: SPI Flash: 25Q64CSIG, SOUND: TPA3113D2, DC / DC: RT6919B
Tuner: NoName
Specifications 32LE7020
AIWA 32LE7020
General repair guidelines for TV LCD LED
Possible manifestations of defects
- AIWA 32LE7020 does not turn on, the indicators on the front panel do not light or flash. The TV does not respond to the control buttons and the remote control.
In such cases, the AC / DC voltage converter is often faulty, which is combined with the main board 5800-A6M31G-0P10. In the absence of the necessary supply voltages in the secondary circuits of the converters, it is necessary to check the power switches and rectifier diodes for a possible partial or complete breakdown.
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.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damping circuits, as well as in Negative Stabilization Feedback. PWM circuits (PWM) LNK6778K are usually checked by replacing with new, or obviously working.
- There is no image, there is sound, it responds to the remote control, the channels are switched. In some cases, the image appears when you turn on and immediately disappears.
As a rule, in such cases there is no display backlight. 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.
When diagnosing, it is necessary to take into account that it is impossible to check the open in the chain of LED lines without disassembling the panels using a tester or multimeter. To open all PN junctions connected in series, a voltage of the order of several tens of volts is required, and ideally, a current source. By opening the panel, each LED can be checked separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect probes in the forward direction to it. 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 indicator on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the 5800-A6M31G-0P10 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 chip replacement SPI Flash: 25Q64CSIG, SOUND: TPA3113D2 are made 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.
Attention TV owners! Self-repair attempts by AIWA 32LE7020 are not recommended by the manufacturer and can lead to serious negative consequences!

FIRMWARE FOR SPI FLASH  ----------->   AIWA 32LE7020 V1R07, Main: 5800-A6M31G-0P10 VER:00.0, Panel: LC320DXJ (SH)(A2)

 To reduce the backlight current, the total resistance of the resistors relative to the housing on the ISET pin of the MP3398A should be proportionally increased. ISET (current setting) - pin 8 in the SOIC-20 package or pin 6 in the SOIC-16 package.

Repair MainBoard
The appearance of the MainBoard 5800-A6M31G-0P10 is shown in the figure below:
5800-A6M31G-0P10
5800-A6M31G-0P10 can be used in TVs:
AIWA 32LE4020 (Panel LC320DXJ-SHA2 GDL320HY (LD0-008) Rev.00), AIWA 32LE7020 (Panel LC320DXJ (SH)(A2)), ERISSON 32LES71T2 (Panel LC320DXJ-SFA2), ERISSON 32LES70T2 (Panel LC320DXJ (SF)(A2)), SUPRA STV-LC32T650WL (Panel LC320DXJ-SFA2 RDL320HY(LD0-803)45).
Key Features of AIWA 32LE7020:
Installed matrix (LED-panel) LC320DXJ (SH) (A2).
To power the backlight LEDs, a converter is used, combined with the main board 5800-A6M31G-0P10, controlled by the MP3398A PWM controller. As the power elements of the LED driver, keys of the D4286 type are used.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using LNK6778K microcircuits.
MainBoard - the main board (motherboard) is a 5800-A6M31G-0P10 module, using SPI Flash chips: 25Q64CSIG, SOUND: TPA3113D2, DC / DC: RT6919B and others.
The NoName tuner provides television reception and channel tuning.


 Trademark: AIWA, Model: 32LE7020.
Briefly from the TV: LCD, LED backlight, 32 ", 1366x768, 720p HD, DVR, sound: 12 W, HDMI connectors: 2.
The composition uses MainBoard 5800-A6M31G-0P10 VER: 00.0 and LCD-panel LC320DXJ (SH) (A2). Version V1R07.
The power supply is combined with the MainBoard.
AIWA 32LE7020 TV with LC320DXJ LCD display, 32 "(81 cm) diagonal size in 16: 9 format. The required screen brightness of 280 cd / m² is provided by LED backlighting. Dynamic contrast ratio of 80,000: 1 is achieved by special control of the LEDs. In manufacturing technology The display of this model is implemented LED backlight.
The LC320DXJ (SH) (A2) panel and the 5800-A6M31G-0P10 motherboard software provide high-definition HD viewing at 1366x768 pixels in the 720p (HD Ready) graphic decomposition standard.
Supported media file formats: MP3, WMA, MPEG4, DivX, MKV, JPEG.
The power of the sound system 12 W (2x6 W) provide 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, HDMI x2, MHL, USB. An output for connecting headphones is provided. The digital tuner is capable of receiving television channels in the standards DVB-T MPEG4, DVB-C, DVB-T2, DVB-S2.
Overall dimensions: with stand 735x469x190 mm, without stand 735x434x86 mm.
TV Weight: 4.5 kg.
Attention! The LC320DXJ (SH) (A2) panel of the AIWA 32LE7020 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.