17MB 82 Vestel LCD TV chassis, how to enter the service mode, full schematic and other details

Used with Telefunken, Sharp, Vestel and many other brand LCD TVs.

17MB82S main board is driven by MediaTek MT5820. This IC is capable of handling Video and audio processing, Scaling-Display processing, 3D comb filter, OSD and text processing, LVDS/mini-LVDS transmitting, channel and MPEG2/4 decoding, integrated DVB-T/C demodulator and media center functionality.
TV supports PAL, SECAM, NTSC color standards and multiple transmission standards as B/G, D/K, I/I’, and L/L’ including German and NICAM stereo. Also DVB T, DVB-C are supported internal demodulators of MediaTek IC and DVB-S/S2 is supported with external demodulator.
Sound system output is supplying max. 2x8W ( less 10%THD at max output) for stereo 8Ω speakers.

MxL601 is a highly integrated low-power silicon tuner IC targeting all global analog and digital cable standards as well as digital terrestrial reception standards. Broadband input filtering and channel filtering have been completely integrated on-chip. This integration enables a very compact design requiring a small footprint, low bill-of-materials cost, and low power consumption. A signal at the 753 RF input is filtered and converted to a programmable IF output up to 44MHz. Automatic gain control, LO generation, and channel selectivity functions are completely integrated on the chip, which simplifies boardlevel design. All functions of the IC can be controlled via I2C interface. MxL601 is available in a 4 x 4 mm2 24-pin QFN package.

The TAS5721 is a 15-W stereo or 2x10 W + 1x15 W2.1 device, efficient, digital audio-power amplifier for driving stereo bridge-tied speakers. One serial data input allows processing of up to two discrete audio channels and seamless integration to most digital audio processors and MPEG decoders. The device accepts a wide range of input data and data rates. Awfully programmable data path routes these channels to the internal speaker drivers. The TAS5721 is a slave-only device receiving all clocks from external sources. The TAS5721 operates with a PWM carrier between a 384-kHz switching rate and a 352-KHz switching rate, depending on the input sample rate. Oversampling combined with a fourth- order noise shaper provides a flat noise floor and excellent dynamic range from 20 Hz to 20 kHz.

The DC voltages required at various parts of the chassis and panel is provided by a main power supply unit. MB82S chassis can operate with PW05, IPS60, IPS70, IPS16, IPS17, IPS19, PW25, PW26, PW82-3, PW03, PW04, PW06, PW07 as main power supply and also with 12V adaptor.

Which power board can be used for board to board or cable connection?
Board to board (BTB) : PW05, IPS60, IPS70, IPS16, IPS17, IPS19
Power Cable : PW25, PW26, PW82-3, PW03, PW04, PW06, PW07
The power supplies generate 24V, 12V, 5V, 3,3V and 12V, 5V, 3.3V standby mode DC voltages. Power stage which is on-chassis generates 5V, 3V3 stand by voltage and 12V, 8V, 5V, 3V3, 2.5V, 1,8V and 1,2V supplies for other different parts of the chassis. The blocks on power block diagram is using dependent to main supply. For PW26 and PW27 just common blocks are enough for proper operation.
Short CCT Protection Circuit
Short circuit protection is necessary for protecting chassis and main IC against damages when any Vcc supply shorts to ground. Protect pin should be logic high while normal operation. When there is a short circuit protect pin should be logic low. After any short detection, SW forces LEDs on LED card to blink.

MT5820 (Main IC) (U1)
The MediaTek MT5820 family consists of a backend decoder and a TV controller and offers high integration for advanced applications. It combines a transport de-multiplexer, a high definition video decoder, an audio decoder, a dual-link LVDS transmitter, a mini-LVDS transmitter, an EPI transmitter and an NTSC/PAL/SECAM TV decoder with a 3D comb filter (NTSC/PAL). The MT5820 enables consumer electronics manufactures to build high quality, low cost and feature-rich DTV.
World-Leading Audio/Video Technology: The MT5820 supports Full-HD MPEG1/2/4/h.264/DiviX/VC1/RM/AVS/VP6/VP8 (option) video decoder standards, and JPEG. The MT5820 also supports MediaTek MDDiTM de-interlace solution can reach very smooth picture quality for motions. A 3D comb filter added to the TV decoder recovers great details for still pictures. The special color processing technology provides natural, deep colors and true studio quality video. Also, the MT5820 family has built-in high resolution and high-quality audio codec.
Rich Features for High Value Products: The MT5820 family enables true single-chip experience. It integrates high-quality HDMI1.4a, high speed VGA ADC, LVDS, mini-LVDS, EPI, USB2.0 receiver, TCON (option), panel overdrive (option).
WW Common Platform Capability: Reserved transport stream input is for external demodulator for other countries or areas. TV maker can easily port the same UI to worldwide TV models. Excellent adjacent and co-channel rejection capability grants customers never miss any wonderful stream. Professional error-concealment provides stable, smooth and mosaic-free video quality.

DDR3 SDRAM 1Gb G-die

The 1Gb DDR3 SDRAM G-die is organized as a 8Mbit x 16 I/Os x 8banks device. This synchronous device achieves high speed double-data-rate transfer rates of up to
2133Mb/sec/pin(DDR3-2133)for general applications. The chip is designed to comply with the following key DDR3 SDRAM features such as posted CAS, Programmable CWL, Internal (Self) Calibration, On Die Termination using ODT pin and Asynchronous Reset . All of the control and address inputs are synchronized with a pair of externally supplied differential clocks. Inputs are latched at the cross point of differential clocks (CK rising and CK falling). All I/Os are synchronized with a pair of bidirectional strobes (DQS and DQS) in a source synchronous fashion. The address bus is used to convey row, column, and bank address information in a RAS/CAS multiplexing style. The DDR3 device operates with a single 1.5V ± 0.075V power supply and 1.5V ± 0.075V VDDQ. The 1Gb DDR3 G-die device
is available in 96ball FBGA(x16).

Features
• JEDEC standard 1.5V ± 0.075V Power Supply
• VDDQ = 1.5V ± 0.075V
• 533MHz fCK for 1066Mb/sec/pin, 667MHz fCK for 1333Mb/sec/pin, 800MHz fCK for 1600Mb/sec/pin, 933 MHz fCK for 1866Mb/sec/pin,
1066 MHz fCK for 2133Mb/sec/pin
• 8 Banks
• Programmable CAS Latency(posted CAS): 5, 6, 7, 8, 9, 10, 11, 12, 13, 14
• Programmable Additive Latency: 0, CL-2 or CL-1 clock
• Programmable CAS Write Latency (CWL) = 6 (DDR3-1066),

7 (DDR3-1333), 8 (DDR3-1600), 9 (DDR3-1866), 10 (DDR3-2133)
• 8-bit pre-fetch
• Burst Length: 8 (Interleave without any limit, sequential with starting address “000” only), 4 with tCCD = 4 which does not allow seamless read or write [either On the fly using A12 or MRS]
• Bi-directional Differential Data-Strobe
• Internal(self) calibration : Internal self calibration through ZQ pin (RZQ : 240 ohm ± 1%)
• On Die Termination using ODT pin
• Average Refresh Period 7.8us at lower than TCASE 85°C, 3.9us at 85°C < TCASE < 95 °C
• Asynchronous Reset
• Package : 96 balls FBGA - x16
• All of Lead-Free products are compliant for RoHS
• All of products are Halogen-free.

EN25Q64 64 Megabit Serial Flash Memory with 4Kbyte Uniform Sector

The EN25Q64 is a 64 Megabit (8192K-byte) Serial Flash memory, with advanced write protection mechanisms. The EN25Q64 supports the standard Serial Peripheral Interface (SPI), and a high performance Dual output as well as Quad I/O using SPI pins: Serial Clock, Chip Select, Serial DQ0(DI), DQ1(DO), DQ2(WP) and DQ3(NC). SPI clock frequencies of up to 50MHz are supported allowing equivalent clock rates of 100MHz for Dual Output and 200MHz for Quad Output when using the Dual/Quad Output Fast Read instructions. The memory can be programmed 1 to 256 bytes at a time, using the Page Program instruction. The EN25Q64 is designed to allow either single Sector/Block at a time or full chip erase operation. The EN25Q64 can be configured to protect part of the memory as the software protected mode. The device can sustain a minimum of 100K program/erase cycles on each sector or block.

EN25QH16 16 Megabit Serial Flash Memory with 4Kbyte Uniform Sector

The EN25QH16 is a 16 Megabit (2,048 K-byte) Serial Flash memory, with enhanced write protection mechanisms. The EN25QH16 supports the standard Serial Peripheral Interface (SPI), and a high performance Dual/Quad output as well as Dual/Quad I/O using SPI pins: Serial Clock, Chip Select, Serial DQ0(DI), DQ1(DO), DQ2(WP) and DQ3(HOLD). SPI clock frequencies of up to 80MHz are supported allowing equivalent clock rates of 160MHz (80MHz x 2) for Dual Output and 320MHz (80MHz x 4) for Quad Output when using the Dual/Quad I/O Fast Read instructions. The memory can be programmed 1 to 256 bytes at a time, using the Page Program instruction. The EN25QH16 is designed to allow either single Sector/Block at a time or full chip erase operation. The EN25QH16 can be configured to protect part of the memory as the software protected mode. The device can sustain a minimum of 100K program/erase cycles on each sector or block.

I-LM1117/LM 800mA Low-Dropout Linear Regulator
The LM1117 is a series of low dropout voltage regulators with a dropout of 1.2V at 800mA of load current. It has the same pin-out as National Semiconductor’s industry standard LM317.
The LM1117 is available in an adjustable version, which can set the output voltage from 1.25V to 13.8V with only two external resistors. In addition, it is also available in five fixed voltages, 1.8V, 2.5V, 2.85V, 3.3V, and 5V. The LM1117 offers current limiting and thermal shutdown. Its circuit includes a zener trimmed bandgap reference to assure output voltage accuracy to within ±1%. The LM1117 series is available in SOT-223, TO-220, and TO-252 D-PAK packages. A minimum of 10μF tantalum capacitor is required at the output to improve the transient response and stability.

Service menu

In order to enter the service menu, First Press “MENU” Then press the remote control code two times, which is “4725”.

USB operations option cannot be used directly. It can be used for updating panel tool, hw configuration etc.

Software update

In MB82 project there is only one software. From following steps software update procedure can be seen:
1. MB82.bin directly inside of a flash memory(not in a folder).
2. Put flash memory to the tv when tv is powered off.
3. Power on the and pre OK button on the remote control when the TV is opened.
4. If First Time Installition screen comes, it means software update procedure is successful.

Schematic

No Backlight Problem
Problem: If TV is working, led is normal and there is no picture and backlight on the panel.
Possible causes: Backlight pin, dimming pin, backlight supply, standby off pin Backlight pin should be high in open position. If it is low, please check Q30 and panel cables.

Dimming pin should be high or square wave in open position. If it is low, please check S16 for Mstar side and panel or power cables, connectors.

Backlight power supply should be in panel specs.  check CN4 for MB82, related connectors for power supply cards.

STBY_ON/OFF should be low for standby on condition, check R2090.

CI Module Problem
Problem: CI is not working when CI module inserted.
Possible causes: Supply, supply control pin, detect pins, mechanical positions of pins CI supply shoul be 5V when CI module inserted. If it is not 5V  check CI_POWER_CTRL, this pin should be low.

Check mechanical positions of CI module.
Detect ports should be low. If it is not low please check CI connector pins, CI module pins and 3V3_VCC on MB82.

Led Blinking Problem
Problem: LED blinking, no other operation
This problem indicates a short on Vcc voltages. Protect pin should be logic high while normal operation. When there is a short circuit protect pin will be logic low. If you detect logic low on protect pin, unplug the TV set and control voltage points with a multimeter to find the shorted voltage to ground.

IR Problem
Problem: LED or IR not working
Check LED card supply on MB82 chassis.

No Sound Problem
Problem: No audio at main TV speaker outputs.
Check supply voltages of VDD_AUDIO, 5V_VCC or 12V_VCC with a voltage-meter.
There may be a problem in headphone connector or headphone detect circuit (when headphone is connected, speakers are automatically muted). Measure voltage at
HP_DETECT pin, it should be 3.3v.

Standby On/Off Problem
Problem:
Device cannot boot, TV hangs in standby mode.
There may be a problem about power supply. Check 12V_VCC, 5V_VCC and 3V3_VCC with a voltage-meter. Also there may be a problem about SW. Try to update TV with latest SW. Additionally it is good to check SW printouts via hyper-terminal (or Teraterm). These printouts may give a clue about the problem.

No Signal Problem
Problem: No signal in TV mode.
Check tuner supply voltage; 3V3_TUN. Check tuner options are correctly set in Service menu. Check AGC voltage at IF_AGC pin of tuner.