Technical description and composition of the ERISSON 19LET21 TV, type of panel and applicable modules. The composition of the modules.ERISSON LED
Model: 19LET21
Chassis / Version: 40-MTK23L-MAI2XG
Panel: M185B3-LA1
MainBoard: 40-MTK23L-MAI2XG
IC MainBoard: CPU: MT8223LFMU; SPI Flash: 25Q32;
Tuner: 07-380-FF5-NA1G
Specifications 19LET21
ERISSON 19LET21
General repair guidelines for TV LCD LED
Repair of the ERISSON 19LET21 TV should begin with a fault diagnosis, which involves a careful examination of the external and internal elements of the device. Sometimes, based on visible changes in the components of the device, it is possible to draw some conclusions and determine the direction of further troubleshooting even before the necessary measurements are taken. Elements with visible damage, for example, capacitors swelled up after boiling the electrolyte, charred resistors in certain nodes of the circuit, as well as ring cracks in solders will help the master to guess the causes and possible consequences of the malfunction.
If the 19LET21 TV does not turn on, does not make any sounds when it is turned on, and also no indicators on the front panel light or blink - there is a high probability of a malfunction in the power module. In some cases, only the stabilizer or power converter of the control processor may be faulty, which is typical for some ERISSON models. When diagnosing and repairing the power supply, after replacing the swollen capacitors of the secondary rectifier filters (if any), you must first check the mains fuse. When it is broken, the power elements of transistors and rectifier bridge diodes should be checked for avalanche (thermal) breakdown.
If a breakdown of the power switch is detected, it should be remembered that in a switching power supply (IIP) it does not fail by itself without any reasons that should be sought by checking other elements of the primary circuit - electrolytic capacitors, a PWM controller, which can only be checked replacement, as well as other semiconductor elements (diodes, transistors, zener diodes).
Sometimes the ERISSON 19LET21 TV does not have an image, but there is sound, or the image appears and immediately disappears. In this case, there is a high probability of a malfunction of the converter for the backlight LEDs of the M185B3-LA1 panel, or a break in the LED circuit is possible. In such cases, first of all, it is necessary to verify the serviceability of all the electrolytic capacitors of the filter by supplying the LED driver itself, including in the power supply unit (power supply unit).
To check the health of the LEDs and contact connections in their power circuit, the panel must be disassembled.
It is impossible to check the LED line for breaks without disassembling the panel with a multimeter or tester. For these purposes, it is necessary to open all series-connected PN junctions and a voltage of the order of tens of volts will be required, and ideally, a current source.
Repair or diagnostics of the 40-MTK23L-MAI2XG motherboard should begin by checking the stabilizers or power converters of its microcircuits. If necessary, you should update the software (software).
Sophisticated MB board repair (SSB) is in some cases possible and practiced by repairmen. To do this, check and, if necessary, replace the CPU elements: MT8223LFMU; SPI Flash: 25Q32; . BGA chip malfunctions are usually easy to detect by warming up.
If you suspect a malfunction of the tuner 07-380-FF5-NA1G, first of all, you need to make sure that there is a supply voltage on the corresponding output of the tuner.
It should be remembered! Attempts to repair the ERISSON 19LET21 TV, in the absence of the necessary qualifications and experience, are categorically not recommended and are fraught with negative consequences, up to the complete non-repairability of the device!
FIRMWARE FOR SPI FLASH -----------> ERISSON 19LET21 , Main: 40-MTK23L-MAI2XG, Panel: M185B3-LA1
The appearance of the MainBoard 40-MTK23L-MAI2XG is shown in the figure below:
40-MTK23L-MAI2XG
40-MTK23L-MAI2XG can be used in TVs:
ERISSON 24LET11 (Panel V236H1-LE2), ERISSON 19LET21 (Panel M185B3-LA1).
Main features of the ERISSON 19LET21 device:
Installed matrix (LED-panel) M185B3-LA1.
The required supply voltage for all nodes of the TV ERISSON 19LET21 provides a switching power supply.
MainBoard - the main board (motherboard) is a 40-MTK23L-MAI2XG module, using CPU chips: MT8223LFMU; SPI Flash: 25Q32; and others.
The tuner 07-380-FF5-NA1G provides television reception and channel tuning.
Additional technical information about the panel:
Brand: CMO
Model: M185B3-LA1
Type: a-Si TFT-LCD, Panel
Diagonal size: 18.5 inch
Resolution: 1366x768, WXGA
Display Mode: TN, Normally White, Transmissive
Active Area: 409.8x230.4 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Brightness: 250 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (8-bit), CIE1931 70%
Response Time: 1.3 / 3.7 (Tr / Td)
Frequency: 60Hz
Lamp Type: 13S8P WLED Without Driver
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V
ERISSON 19LET21 TV with an M185B3-LA1 LCD display, 19 "(48 cm) diagonal size in 16: 9 format. The LED panel of this TV has LED backlighting - 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 analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, JPEG. The audio is realized by two built-in speakers using the NICAM STEREO audio processing system.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV x2, audio x3, component, VGA, HDMI, USB. 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, 1280x1024.
Overall dimensions: With stand 769x536x196 mm, Without stand 392x260x40 mm.
Attention! The M185B3-LA1 panel of an ERISSON 19LET21 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.