Technical description and composition of the TOSHIBA 26EL834RB TV, type of panel and applicable modules. The composition of the modules.TOSHIBA LED
Model: 26EL834RB
Panel: LC260EXN SD A3
PWM LED driver: LED
Power Supply (PSU): DPS-92CP A
PWM Power: DDA014 (PWM Resonant), 1608B (PFC), DDA010 (Standby)
MainBoard: 32AV833 Rev: 1.03
IC MainBoard: MSD3704PX-LF-SA, 25064CVSIG, TAS5707L
Tuner: TDTK-G641D
Specifications 26EL834
TOSHIBA 26EL834RB
General repair guidelines for TV LCD LED
Repair of electronic equipment usually begins with its external inspection and diagnosis of the malfunction. In this case, you should examine all the internal components of the TOSHIBA 26EL834RB TV, as well as the external elements of the housing. Visible damage to elements can sometimes indicate the direction of the search for a defect even before the necessary measurements are taken. In most cases, the repairman can guess the causes of the defect and possible consequences by the characteristic signs of typical TV defects, for example, ring cracks formed in the soldering of element leads, swollen rectifier filter capacitors, charred resistors and other circuit elements.
If the 26EL834RB 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 regulator or power converter of the control processor may be faulty, which is typical for some TOSHIBA models. In the absence of swollen filter capacitors of the secondary rectifiers, the diagnostics of the power supply should be started by checking the fuse and, if it is broken, it is first necessary to check all the power semiconductor elements of the primary circuit - diodes and transistors for the possibility of an avalanche or 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, PWM controller ICE DAA010, which should be checked it is possible only by replacement, as well as other semiconductor elements (diodes, transistors, zener diodes).
If the TOSHIBA 26EL834RB TV does not have an image, but there is sound, a malfunction in the LED backlight circuits of the LC260EXN SD A3 panel is likely. It is also necessary to check the serviceability of the electrolytic capacitors of the filter of the secondary rectifiers of the BP (power supply) for an overstated ESR.
In most cases of lack of backlight, it becomes necessary to disassemble the panel in order to check the LEDs, connectors, loops and all contact connections. If one or several LEDs does not work in one line, therefore, they are broken and should be replaced.
It is impossible to detect a break in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and to open their transitions, a voltage of several tens of volts is required. Ideally, a current source is suitable for such purposes.
Often, the MB (SSB) card must be replaced in case of complex malfunctions that are difficult to detect. When trying to repair, you should check its elements - 32AV833rev1.03 and replace failed chips with new ones. Some malfunctions may be due to the use of BGA soldering technologies in modern Main Board technologies. Typically, such defects are detected by local heating of the chip.
The TDTK-G641D tuner malfunction is established after checking the software and all the supply voltages at its terminals, including the varicap supply voltage (30-33V).
Remember! Attempts to self-repair by users of the TOSHIBA 26EL834RB TV without the appropriate qualifications and the necessary experience can lead to serious negative consequences!
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> Toshiba 26EL833G 32AV833
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> Toshiba 32AV833
Service Manual 42 pages of 2010 on the models 26EL834G, 26EL834RB, 32EL834B, 32EL834G, 32EL834R, 32HL834G, 32HL834R, 42HL834G, 42HL834R
The appearance of the MainBoard 32AV833 is shown in the figure below:32AV833
32AV833 can be used in TVs:
TOSHIBA 26EL833RB (Panel LC260EXN (SD)(A3) 75023140), TOSHIBA 26EL834RB (Panel LC260EXN SD A3), TOSHIBA 32AV833RB (Panel LC320WXN SCC1), TOSHIBA 32EL833G (Panel LC320EXN (SD)(A2)), TOSHIBA 32EL833R 32EL834R (Panel LC320EXN-SDA2 75023687 LCD PANEL), TOSHIBA 32HL833R (Panel LC320EUN SD V1 75022862 LED), TOSHIBA 32HL834R (Panel LC320EUN (SD)(V1)), TOSHIBA 32LV833RB (Panel T315HW04 V4), TOSHIBA 40LV833RB (Panel V400H1-L10), TOSHIBA 42DB833R (Panel LC420EUN (SD)(V1) 75023049), TOSHIBA 42HL833R (Panel LC420EUN (SD)(V1) LED 75023049), TOSHIBA 42HL834R (Panel LC420EUN (SD)(V1)).
PSU Advanced
According to the conditions of compliance with modern world standards for household switching power supplies, the DPS-92CP module provides for the use of a Power Factor Correction unit. The PFC circuit is a flyback converter based on the 1608B PWM controller. The reactance of an electrolytic capacitor of a line filter at a frequency of 50-60 Hz is usually not more than 20-30 ohms and its charge directly from the network through open diodes could reach tens of amperes per pulse if no filtering were applied.
As a result of the PFC conversion, an increased voltage on the capacitor (about 380V) cannot directly open the rectifier diodes, on the anode of which the voltage will always be slightly less (about 300V) and then its charging current will always be limited by the elements of the PWM controller. As a result, the envelope of the high-frequency pulses of the consumed current will repeat the shape and phase of the input sinusoidal voltage. The presence of an increased voltage (+ 380V) on the network capacitor indicates the serviceability of the PFC node.
The appearance of the power supply
Main features of the TOSHIBA 26EL834RB device:
Installed matrix (LED panel) LC260EXN SD A3.
A converter controlled by a PWM LED controller is used to power the backlight LEDs.
The necessary supply voltages for all nodes of the TOSHIBA 26EL834RB TV are generated by the DPS-92CP power supply module or its analogs using the DDA014 (PWM Resonant), 1608B (PFC), DDA010 (Standby) microcircuits.
MainBoard - the main board (motherboard) is a 32AV833 module, using microchips MSD3704PX-LF-SA, 25064CVSIG, TAS5707L and others.
The TDTK-G641D tuner provides television reception and channel tuning.
Additional technical information about the panel:
Brand: LG Display
Model: LC260EXN-SDA3
Type: a-Si TFT-LCD, Panel
Diagonal size: 26.0 inch
Resolution: 1366x768, WXGA
Display Mode: S-IPS, Normally Black, Transmissive
Active Area: 575.769x323.712 mm
Surface: Antiglare (Haze 10%), Hard coating (3H)
Brightness: 350 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (6-bit + Hi-FRC), CIE1931 68%
Response Time: 6 (G to G)
Frequency: 60Hz
Lamp Type: WLED Embedded (LED Driver)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 12.0V
TOSHIBA 26EL834 LED TV with LC260EXN LCD, 26 "(66 cm) diagonal size 16: 9 format. The required brightness of the screen is 400 cd / m² LED LED backlighting. The ratio of maximum brightness to minimum (contrast) is 1000: 1 Dynamic contrast ratio of 3,000,000: 1 is achieved by special control of the LEDs. This model uses side LED backlighting from Edge LEDs. You can view images in high quality HD at a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready). Audio or video signal can be processed in analogue 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, MPEG4, Xvid, MKV , JPEG.
The power of the sound system 10 W (2x5 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, audio x2, component, SCART, RGB, VGA, HDMI x2, 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, 1280x1024, 1360x768.
A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C standards.
The power consumed by the TV in the operating mode from the network is 41 watts.
Overall dimensions: with stand 643x468x181 mm, without stand 643x420x45 mm.
TV Weight: with stand: 6.5 kg, without stand: 5.6 kg.
Attention! The TOSHIBA 26EL834 LED TV panel LC260EXN SD A3 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.