Technical description and composition of the ERISSON 32LET42T2 TV, type of panel and applicable modules. The composition of the modules.ERISSON LED
Model: 32LET42T2
Chassis / Version: MT31BP
Panel: LVW320CSOT E274 V2
LED driver (backlight): integrated into MainBoard
PWM LED driver: MP3398A
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6 (RT7738)
MainBoard: 40-MT31BP-MAA2LG
IC MainBoard: CPU: MT5531NDNT; SPI Flash: 25Q64F; SOUND: RT9108NB
Tuner: ST34WN-2T-E
Specifications 32LET42T2
ERISSON 32LET42T2
General repair guidelines for TV LCD LED
In the case when the 32LET42T2 does not turn on, does not respond to the remote control and buttons on the front panel, does not blink light bulbs and does not show any signs of operability, the power supply module that is combined with the MainBoard is probably defective in this case. When repairing the power supply, it is advisable to start the diagnostics by checking the mains fuse and the electrolytic capacitors of the filters of the converter secondary rectifiers. In the event of a fuse breaking, the reason should be sought in the power semiconductor elements of the pulse converter of the main power supply. First of all, it is necessary to check the diodes of the rectifier bridge of the mains voltage and the power key (s) of the converter. The complete inoperability of the power supply unit can be caused by a short circuit in the power elements in the primary circuit, followed by an open fuse, or a short circuit in the loads.
It should be remembered that in the practice of repair, usually the power switches in switching power supplies (SMPS) do not fail due to their poor quality and, in such cases, it is necessary to look for the cause that led to a malfunction and provoked a breakdown of the key. Most often, the culprits of the accident are dried electrolytic capacitors or dangling resistors in the primary circuit, or the PWM controller chip itself may be faulty. It is also necessary to check all the semiconductor elements of the stabilization circuit in the primary and secondary circuits.
If the ERISSON 32LET42T2 has no image, there is sound and the channels are switched, there is a possibility of a malfunction in the backlight LED circuit of the LVW320CSOT E274 V2 panel, or their power converter - LED driver. Sometimes, when turned on, the image appears and immediately disappears. In such cases, it is necessary to check the electrolytic capacitors of the power filter of the backlight unit.
To check the health of the LEDs, as well as contact connections in the ruler circuit, it is necessary to disassemble the panel.
A break in the line of LEDs connected in series cannot be detected with a multimeter or tester without disassembling the panel. To open all the transitions, several tens of volts are needed, and it is best to use a current source for such purposes.
When trying to repair the motherboard, you should first check the serviceability of linear stabilizers or power converters of microcircuits and, if necessary, update the software (software).
Board repair and replacement of CPU chips: MT5531NDNT; SPI Flash: 25Q64F; SOUND: MP3398A are manufactured 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 you suspect a malfunction of the ST34WN-2T-E tuner, first of all, you need to make sure the software is correct, as well as the presence of the necessary voltage levels at the corresponding terminals of the tuner.
Attention! For users and owners of 32LET42T2 TVs who do not have the appropriate qualifications, knowledge and experience, we categorically do not recommend attempting self-repair in order to avoid negative consequences that could lead to complete non-repairability of the device.
The appearance of the MainBoard 40-MT31BP-MAA2LG is shown in the figure below:40-MT31BP-MAA2LG
40-MT31BP-MAA2LG can be used in TVs:
ERISSON 32LET82 (Panel LVW320CSOT E145 V2), ERISSON 32LET42T2 (Panel LVW320CSOT E274 V2), ERISSON 32LET41T2 (Panel LVW320CS0T E274 V2), FUSION FLTV-32T21 (Panel LVW320CZOT), SUPRA STV-LC32T420WL (Panel LVW320CSOT E155 V2), SUPRA STV-LC32T850WL (Panel LVW320CSOT E45 V1), SUPRA STV-LC28T662WL (Panel T8-28T3520-LPM20), SUPRA STV-LC24T850WL (Panel 720p HD 1366x768), TELEFUNKEN TF-LED32S29T2 (Panel LVW320CS0T E198 V4), TELEFUNKEN TF-LED24S29T2 (Panel V236BJ1-LE2 Rev.C1), THOMSON T24E12DHU-01B T24E12DHU (Panel LVW240AUDX E2 V6).
Main features of the ERISSON 32LET42T2 device:
Installed matrix (LED-panel) LVW320CSOT E274 V2.
To power the backlight LEDs, a converter is used, combined with the main board 40-MT31BP-MAA2LG, controlled by the MP3398A 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 (RT7738) microcircuits.
MainBoard - the main board (motherboard) is a 40-MT31BP-MAA2LG module, using CPU chips: MT5531NDNT; SPI Flash: 25Q64F; SOUND: RT9108NB and others.
The ST34WN-2T-E tuner provides television reception and channel tuning.
Trademark: ERISSON, Model: 32LET42T2.
Shortly from the TV: LCD, 720p HD, diagonal 32 "(81 cm), there is HDMI, there is USB, there is support for DVB-T2, the type of backlight: Edge LED.
The composition uses MainBoard 40-MT31BP-MAA2LG and an LCD panel (matrix) LVW320CSOT E274 V2. The power supply is combined with the MainBoard.
ERISSON 32LET42T2 TV with LVW320CSOT LCD, 32 "(81 cm) diagonal size in 16: 9 format. The required brightness of the screen is 240 cd / m² LED backlighting. Contrast as the ratio of maximum brightness to minimum is 3000: 1. The LED panel of this TV is equipped with an end LED backlight - Edge LED. You can view images in high quality HD at a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready). The input high-frequency or video signal can be processed in an analog system max PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in the standards 480i, 480p, 576i, 576p, 720p, 1080i. Supported media file formats: MP3, WMA, MPEG4, MKV, JPEG.
The power of the sound system 10 W (2x5 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, S-Video, VGA, HDMI, USB. An output for connecting headphones is provided. To connect a computer or laptop to this TV model, a VGA (D-Sub 15) connector is used on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768, 1360x768.
A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Overall dimensions: With a support 1111x708x296 mm, Without a support 736x475x81 mm.
Attention! The LVW320CSOT E274 V2 panel of an ERISSON 32LET42T2 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.
