Technical description and composition of the TOSHIBA 20JL7R TV, type of panel and applicable modules. The composition of the modules.TOSHIBA LED
Model: 20JL7R
Panel: T201VN01 V1
LED driver (backlight): DAC-19B023 23078216
PWM LED driver: OZ960SN
MOSFET LED driver: AO4606
Power Supply (PSU): TAA-Y59 19v / 4.2a
PWM Power: 7501 (8), L6561D (PFC)
MOSFET Power: 11N65C3
MainBoard: PD1803 / PD1860
IC MainBoard: MN101E02HXX, GM2221, 24LC16
Tuner: EC981W1
Specifications 20JL7R
TOSHIBA 20JL7R
General repair guidelines for TV LCD LED
TOSHIBA 20JL7R, like other televisions, it is advisable to start repairing with a careful examination of the external and internal elements and modules. 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.
In cases when the TOSHIBA 20JL7R TV does not turn on, does not respond to the remote control and buttons, any indicators on the front panel do not light up or blink, and there are no sounds and no signs of operability when turning on, the TAA-Y59 19v / power module is most likely to be faulty 4.2a or there is no processor power on the motherboard (a typical defect of some TOSHIBA TVs). First of all, it is necessary to replace the swollen capacitors of the rectifier filters, if any. If the mains fuse is broken in the power supply, in most cases a breakdown of the power key (s) 11N65C3 is detected, which can be integrated with a PWM controller, or a separate field-effect transistor can be used. The rectifier bridge diodes and the electrolytic capacitor of the mains rectifier filter should also be checked.
Mos-Fet keys used in switching power supplies (SMPS) rarely fail for no reason to look for when checking other circuit elements. Often the breakdown is caused by malfunctions of electrolytic capacitors or semiconductor elements in the primary circuit, or by a break in the resistors in the stabilization circuits. The PWM controller chip 7501 (8) L6561D (8) can also cause a breakdown of the power switch of the converter.
In cases where the TOSHIBA 20JL7R TV has lost an image, and the sound is there and all other functions are operational, there is a possibility of a malfunction of the LED driver (converter for powering the backlight LEDs of the panel 23301618). When you turn on the TV, the image may appear briefly and disappear immediately. It must be borne in mind that with such manifestations the LEDs themselves also fail.
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.
A break in the line of LEDs connected in series cannot be detected with a multimeter or tester without disassembling the panel. To open all the transitions, several tens of volts are needed, and it is best to use a current source for such purposes.
Remember! Attempts by users to repair the TOSHIBA 20JL7R TV independently without the appropriate qualifications and necessary experience can lead to serious negative consequences!
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> Toshiba 14JL7E, 14JL7H, 14JL7R, 20JL7E, 20JL7H, 20JL7R
The TAA-Y59 power supply module is made using the Power Factor Correction (PFC) scheme to eliminate multiple AC harmonics introduced into the power supply by the device. The PFC assembly is a Step-Up Converter based on the L6561D PWM controller, which evenly distributes high-frequency impulses of the charging current of the electrolytic capacitor of the rectifier filter of the mains voltage over a period of 50 Hz. The current of its charge in this case will already be determined not by its reactance (usually 10-30 ohms for the network frequency), but by the elements of the converter. As a result, a change in the amplitude of the pulses (envelope) of the consumed current of the converter will repeat the shape and phase of the input sinusoidal voltage. The availability of an increased voltage (about + 380V) in the operating mode on the capacitor of the line filter indicates the serviceability of the PFC node.Key Features of the TOSHIBA 20JL7R:
Installed matrix (LED-panel) T201VN01 V1.
The LED driver DAC-19B023 is used to power the backlight LEDs, it is controlled by the OZ960SN PWM controller. As power elements of the LED driver, keys of the AO4606 type are used.
The necessary supply voltages for all nodes of the TOSHIBA 20JL7R TV are generated by the TAA-Y59 power module or its analogs using microcircuits 7501 (8), L6561D (PFC) and power switches of the 11N65C3 type.
MainBoard - the main board (motherboard) is a PD1803 module, using microcircuits MN101E02HXX, GM2221, 24LC16 and others.
The EC981W1 tuner provides television reception and channel tuning.
Additional technical information about the panel:
Brand: AU Optronics
Model: T201VN01 V1
Type: a-Si TFT-LCD, Panel
Diagonal size: 20.1 inch
Resolution: 640x480, VGA
Display Mode: MVA, Normally Black, Transmissive
Active Area: 408x306 mm
Surface: Antiglare, Hard coating (3H)
Brightness: 500 cd / m²
Contrast Ratio: 800: 1
Display Colors: 16.7M (8-bit)
Response Time: 16 (G to G)
Frequency: 60Hz
Lamp Type: 12 pcs CCFL Without Driver
Signal Interface: LVDS (1 ch, 8-bit), 20 pins
Voltage: 5.0V
In some cases, before calling the repair service, you should make sure that your TV is really defective.
If the TOSHIBA 20JL7R does not turn on or periodically turns off, it is useful to check the sockets and extension cords at the points where the TV is connected to the network, for example, using a regular table lamp.
If the TOSHIBA 20JL7R does not respond to the remote control, but the control buttons on the panel work, there is a certain probability of a malfunction of the remote control (the remote does not work). It is advisable to check or replace the batteries in it.
If, while watching broadcasting programs, a signal of no signal appears (no signal), you should make sure that the TV is in the TV reception mode (digital / analog), or check the antenna or cable equipment.
You can check the operation of the TV from other external devices.
If there is no sound only when watching analog television programs, you should check the sound system in the settings. For Russia, D / K (6.5 MHz), for European countries B / G (5.5 MHz). In modern TVs, a region is usually chosen to set the color and sound standards - for Russia, “East Europe” (Eastern Europe).
If the TOSHIBA 20JL7R hangs during operation, does not respond to either the remote control or the buttons on the control panel, sometimes rebooting helps. To do this, you must completely disconnect the TV from the network by pulling the plug from the outlet, and turn it back on after 10-15 seconds.