Toshiba
Model: 20V300PR
Chassis / Version: PE0312
Panel: A201SN02 V5
T-CON: A201SN02 V5 CTRL BD
Inverter (backlight): V71A00000700 MPT T028
PWM Inverter: MR1038EY
MOSFET Inverter: A2755
Trans Inverter: T01-010002J / 1
Power Supply (PSU): V71A00000700 MPT T028
PWM Power: SG5841JSC, CM3406DS
MOSFET Power: 2SK3115
Mainboard: PE0312
IC MainBoard: CPU: R8A02037A52FP L724001, 29LV400CTTC-70G
Tuner: TAEA G055D
Control: CT-90279
Specifications 20V300R
TOSHIBA 20V300PR
General recommendations for repairing TV LCD
Possible malfunctions
- TOSHIBA 20V300PR does not turn on, does not respond to buttons and remote control, indicators on the front panel do not light up and do not blink.
Usually, with such manifestations, the defect is caused by faulty elements in the main power supply module V71A00000700. Then it is necessary to measure its output voltages and, in case of their complete or partial absence, it is necessary to check the serviceability of power switches (2SK3115) and rectifier diodes of converters for possible short circuit.
In case of any breakdowns in the secondary circuits, the converter can operate in emergency short-circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse or the current sensor at the source of the key more 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. SG5841JSC PWM controllers, in the absence of visible damage or open faults between the terminals, are checked by replacing them with new ones, or obviously working ones.
- There is no image, there is sound, all other functions of the TV work. When turned on, the image may sometimes appear for a second.
The defect can be caused by problems in the nodes or elements of the backlight of the display, or in the power supply of the lamps or inverter. If all the electrolytic capacitors of the filter according to the power supply of the inverter are working, make sure that the lamps are working, then you need to check the converter keys and the secondary windings of the transformers.
Sometimes, for diagnostic purposes, it is necessary to disable the inverter protection. In such cases, special care must be taken during work, and the protection circuit should be restored immediately after the repair is completed.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the PE0312 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). 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: R8A02037A52FP L724001, 29LV400CTTC-70G. BGA chip malfunctions are usually easy to detect by warming up.
Before changing the tuner TAEA G055D, if there is no possibility of tuning to television channels, you should make sure that there are supply voltages that must be measured at 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
Owners and users of the TOSHIBA 20V300PR TV should remember that self-repair without special knowledge, skills and qualifications can be fraught with negative consequences that can lead to complete non-repairability of the device!
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> Toshiba 20V300P Main PE0312
The appearance of MainBoard PE0312 is shown in the figure below:PE0312
PE0312 can be used in TVs:
TOSHIBA 20V300PR (Panel A201SN02 V5), TOSHIBA 20V300R 20V300PR (Panel A201SN02 V.5).
Main features of the TOSHIBA 20V300PR device:
Installed matrix (LCD panel) A201SN02 V5.
The matrix control uses the Timing Controller (T-CON) A201SN02.
To power the backlight, an inverter V71A00000700 is used, it is controlled by the PWM controller MR1038EY. A transformer T01-010002J / 1 is installed in the inverter converter. As power elements of the inverter, keys of type A2755 are used.
The necessary supply voltages for all nodes of the TOSHIBA 20V300PR TV are generated by the V71A00000700 power module or its analogs using SG5841JSC, CM3406DS microcircuits and 2SK3115 type power switches.
MainBoard - the main board (motherboard) is a PE0312 module using CPU chips: R8A02037A52FP L724001, 29LV400CTTC-70G and others.
The TAEA G055D tuner provides television reception and channel tuning.
Information from an alternative source:
TOSHIBA 20V300PR
Panel Type (Matrix): A201SN02 V.5
Motherboard: PE0312-A1 V28A000351B1, R8A02037A52FP L724001, 29LV400CTTC-70G, R2S15904SP, CD4053B, Tuner: TAEA-G055D (V86A00002500)
T-con: A201SN02 V5 CTRL BD, PSU &
Invertor: MPT T028 P / N: V71A00000700, MPS 0804 MP1038EY, CM3406DS, SG5841JSZ, R2A15106NP, Remote Control CT-90279
Additional technical information about the panel:
Brand: AUO
Model: A201SN02 V5
Type: a-Si TFT-LCD, Panel
Diagonal size: 20.1 inch
Resolution: 800x600, SVGA
Display Mode: TN, Normally White, Transmissive
Active Area: 408x306 mm
Surface: Antiglare
Brightness: 450 cd / m²
Contrast Ratio: 700: 1
Display Colors: 16.2M (6-bit + FRC), CIE1931 72%
Response Time: 11/5 (Tr / Td)
Frequency: 60Hz
Lamp Type: 6 pcs CCFL Without Driver
Signal Interface: TTL (1 ch, 8-bit), 50 pins
Voltage: 5.0V
TOSHIBA 20V300R LCD TV with A201SN02 LCD display, diagonal size 20 "in 4: 3 format. The brightness of the screen is 450 cd / m² with CCFL (EEFL) fluorescent lamps. The ratio of maximum brightness to minimum (contrast) is 500: 1. The input high-frequency or video signal can be processed in analogue systems PAL, SECAM, NTSC. Graphic processing and digital signal generation takes place in the standards 480i, 480p, 576i, 576p, 720p, 1080i.
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 x2, audio x3, S-Video, component, VGA. 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.
The power consumed by the TV in the operating mode from the network is 50 watts.
Overall dimensions: with stand 486x469x200 mm, without stand 486x429x87 mm.
TV Weight: with stand: 8.2 kg, without stand: 7.2 kg.
Attention! The A201SN02 V.5 panel of the TOSHIBA 20V300R LCD TV is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!
