Thursday 23 April 2020

REPAIR / SERVICING TV SHIVAKI STV-24LED16

Technical description and composition of the TV SHIVAKI STV-24LED16, type of panel and applicable modules. The composition of the modules.
SHIVAKI LED
Model: STV-24LED16
Chassis / Version: TP.S512.PA63
Panel: HV236WHB-N00 M00
LED driver (backlight): integrated into PSU
PWM LED driver: SN51DP
MOSFET LED driver: PA1108DA
Power Supply (PSU): integrated into MainBoard
PWM Power: LD5530
MainBoard: TP.S512.PA63
IC MainBoard: CPU: S2T512, SPI Flash: GD25Q64, Audio: YD1517P
Tuner: XF-3SDT-H (R840)
Technical Specifications STV-24LED16
SHIVAKI STV-24LED16
General repair guidelines for TV LCD LED
Possible malfunctions
- The SHIVAKI STV-24LED16 TV does not turn on and does not show any signs of turning on, it does not respond to the control buttons or the remote control.
In such cases, the AC / DC converter of the mains voltage, which is combined with the main board TP.S512.PA63, is often faulty. 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 breakdowns of semiconductors in the secondary circuits of any converter, as a rule, it can operate in emergency short-circuit mode without output voltages, and during short circuit in the elements of the primary circuit, the main fuse and, less often, the current sensor at the source of the key are most often cut off.
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) LD5530, 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 is responding to the remote control. Or immediately after turning on for a second, the image may appear and immediately disappear.
Often in such cases, there is no LED backlight. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
To check the LED strips, to open all the transitions of the LEDs, several tens of volts or more are needed, it is best to use a current source for such purposes. The breakage of several PN junctions connected in series cannot be detected with a multimeter or tester. In such cases, it is necessary to open the panel and check each LED. If your multimeter cannot open the LED transitions in forward bias, you can sometimes detect the presence of a PN junction of the protective zener diode by connecting the probes in the opposite direction. If the zener diode is broken or broken in short-circuit, then the LED is faulty and needs to be replaced.
- 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 TP.S512.PA63 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). When repairing an MB board, you need to check its CPU components: S2T512, SPI Flash: GD25Q64, Audio: YD1517P. Defective items should be replaced. If chips with BGA soldering technology are used, a problem in its implementation is detected by the local heating of the chip.
Before changing the tuner XF-3SDT-H (R840), if it is not possible to tune to television channels, make sure that there are supply voltages that need to be measured on the corresponding terminals of the tuner and check the software for correctness. The pulses of the data exchange of the tuner with the processor can be controlled by an oscilloscope
Attention TV owners! Attempts at self-repair of SHIVAKI STV-24LED16 are not recommended by the manufacturer and can lead to serious negative consequences!


FIRMWARE FOR SPI FLASH  ----------->   SHIVAKI STV-24LED16, Main: TP.S512.PA63, Panel: HV236WHB-N00 M00


The appearance of MainBoard TP.S512.PA63 is shown in the figure below:
TP.S512.PA63
TP.S512.PA63 can be used in TVs: AIWA 24LE7021 (Panel V236BJ1-P03), ERISSON 22LES71T2 (Panel A215EE1TBA-9), FUSION FLTV-24H100T (Panel CM238C01), SUPRA STV-LC22T800FL (Panel C215F14-E1-P), THOMSON T24E14DF-01B (Panel HM236WU3-101).

Main features of the SHIVAKI STV-24LED16 device:
Installed matrix (LED-panel) HV236WHB-N00 M00.
To power the backlight LEDs, a converter is used, combined with a power supply, controlled by the SN51DP PWM controller. As the power elements of the LED driver, keys of the type PA1108DA are used.
The power module is combined with MainBoard and is made according to the flyback AC / DC voltage converter circuit using LD5530 microcircuits.
MainBoard - the main board (motherboard) is a TP.S512.PA63 module, using CPU chips: S2T512, SPI Flash: GD25Q64, Audio: YD1517P and others.
Tuner XF-3SDT-H (R840) provides the reception of television programs and tuning to channels.
TV SHIVAKI STV-24LED16 with LCD HV236WHB-N00, diagonal size 24 "(61 cm) 16: 9 format. The required brightness of the screen 220 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 topics PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, WMA, MPEG4, MKV, JPEG.
The power of the sound system 6 W (2x3 W) provide 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: 640x480, 800x600, 1024x768, 1360x768.
The digital tuner is capable of receiving television channels in the standards DVB-T MPEG4, DVB-C, DVB-T2, DVB-S2.
Overall dimensions: With a support of 560x385x170 mm, Without a support of 560x340x35 mm.
TV Weight: 4 kg.
Attention! The HV236WHB-N00 M00 panel of the SHIVAKI STV-24LED16 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.