Technical description and composition of the TV SHIVAKI STV-20LED14, type of panel and applicable modules. The composition of the modules.SHIVAKI LED
Model: STV-20LED14
Chassis / Version: TP.MS3663S.PA671
Panel: CX195DLEDM
LED driver (backlight): integrated into MainBoard
PWM LED driver: OB3350CP
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MOSFET Power: TO-252
MainBoard: TP.MS3663S.PA671
IC MainBoard: CPU: MSD3663LSA-Z1, SPI FLASH MX25L6436F, AUDIO: YD1517P
Tuner: CDT-9NT372-RF01
Technical Specifications STV-20LED14
SHIVAKI STV-20LED14
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The SHIVAKI STV-20LED14 TV does not turn on, does not respond to the remote control and buttons on the control panel, does not light up or blink indicators.
In this case, the main Switching Power Supply, an AC / DC network voltage converter, whose elements are located on the MainBoard TP.MS3663S.PA671 main board, may be faulty. It is necessary to measure its output voltages and, if they are absent, check the serviceability of power switches (TO-252) and rectifier diodes in the converters for possible breakdown.
In case of breakdowns of semiconductors in 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 power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. PWM SOT23-6 PWM controllers, in the absence of visible damage or obvious short-circuit between the terminals, are checked by replacing with new ones, or obviously working.
- There is no image, but there is sound and all other functions work. Sometimes when you turn on the image for a second appears and disappears.
Usually in such cases, a malfunction is detected in the backlight nodes of the LED panel. More often the reason for this is the breakdown of the LEDs, or poor contact in the connectors of the strips, less often the LED driver may be malfunctioning.
It should be remembered that it is not possible to determine the open circuit in the LED lines without disassembling the panels with a tester or multimeter without an additional device, for example, a current source. To open all PN junctions connected in series at once, a voltage of several tens of volts may be required. Then it is necessary to open the panel and check each LED separately with a multimeter. If the capabilities of your multimeter do not allow you to open the LED in the forward direction or dual LEd are used, then the PN junction of the emergency zener diode can indirectly serve as a health indicator. In case of LED-a failure, the zener diode PN junction will either be cut off or broken into short-circuit.
- The indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the TP.MS3663S.PA671 motherboard should begin by checking the stabilizers and power converters needed to power the microcircuits and matrix. If necessary, update or replace the software (software). Board repair and replacement of CPU chips: MSD3663LSA-Z1, SPI FLASH MX25L6436F, AUDIO: YD1517P are carried out 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.
Before replacing the tuner CDT-9NT372-RF01, if there is no tuning for 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
It should be remembered! Attempts to independently repair the SHIVAKI STV-20LED14 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 -----------> SHIVAKI STV-20LED14, Main: TP.MS3663S.PA671, Panel: CX195DLEDM
The appearance of MainBoard TP.MS3663S.PA671 is shown in the figure below:TP.MS3663S.PA671
Main features of the SHIVAKI STV-20LED14 device:
Installed matrix (LED-panel) CX195DLEDM.
To power the backlight LEDs, a converter is used, combined with the TP.MS3663S.PA671 main board, controlled by the OB3350CP 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 microcircuits and TO-252 type power switches.
MainBoard - the main board (motherboard) is a TP.MS3663S.PA671 module, using CPU chips: MSD3663LSA-Z1, SPI FLASH MX25L6436F, AUDIO: YD1517P and others.
The tuner CDT-9NT372-RF01 provides the reception of television programs and tuning to channels.
TV SHIVAKI STV-20LED14 with LCD display CX195DLEDM, diagonal size 20 "(51 cm) 16: 9 format. The required brightness of the screen 200 cd / m² is provided by LED backlight LED. Contrast, as the ratio of maximum brightness to minimum, is 1000: 1. Edge LED backlighting is realized in the LED-panel of this TV - 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 are performed in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, WMA, MPEG4, MKV, JPEG.
The power of the sound system 10 W (2x5 W) provides 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, component, SCART, 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: 1360x768, 1920x1080.
A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Overall dimensions: with stand 462x305x165 mm, without stand 462x273x76 mm.
TV Weight: 1.9 kg.
Attention! The CX195DLEDM panel of a SHIVAKI STV-20LED14 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.
