Akai 26Inch NTSC TV - software update, V Chip password change, Power board schematic, Universal remote control set-up code list and more....
Used ICs: MT8205G, AT24C02, MX29LV160BBTC. LP2996, AZ1117/H, WM8776, MX232A, ISAV330
Operation of LCD-TV
1. After turning on power switch, power board sends 5Vst-by Volt to Micro Processor IC waiting for ON signals from Key Switch or Remote Receiver.
2. When the ON signal from Key Switch or Remote Receiver is detected, Micro Processor will send ON Control signals to Power. Then Power sends (5Vsc,
12Vsc, 24V and RLY ON, Vs ON) to PCBs working. This time VIF will send signals to display back light, OSD on the panel and start to search available
signal sources. If the audio signals input, them will be amplified by Audio AMP and transmitted to Speakers.
3. If some abnormal signals are detected (for example: over volts, over current, over temperature and under volts), the system will be shut down by Power off.
1. After turning on power switch, power board sends 5Vst-by Volt to Micro Processor IC waiting for ON signals from Key Switch or Remote Receiver.
2. When the ON signal from Key Switch or Remote Receiver is detected, Micro Processor will send ON Control signals to Power. Then Power sends (5Vsc,
12Vsc, 24V and RLY ON, Vs ON) to PCBs working. This time VIF will send signals to display back light, OSD on the panel and start to search available
signal sources. If the audio signals input, them will be amplified by Audio AMP and transmitted to Speakers.
3. If some abnormal signals are detected (for example: over volts, over current, over temperature and under volts), the system will be shut down by Power off.
Basic display theory.
When an electrical field is applied to the LC planes, the LC molecules re-align themselves so that they are parallel to the electrical field. This electrical process
is known as twisted nematic field effect or TNFE. In this alignment, polarized light is not twisted as it passes through the LC material If the front polarizer is oriented perpendicular to the rear polarizer, light will pass through the energized display but will be blocked by the rear polarizer. An LCD in this form is acting as a light shutter.
Displays with variable characters are created by selectively etching away the conductive surface that was originally deposited on the glass. Etched areas become the display’s background; unetched areas become the display’s characters.
When an electrical field is applied to the LC planes, the LC molecules re-align themselves so that they are parallel to the electrical field. This electrical process
is known as twisted nematic field effect or TNFE. In this alignment, polarized light is not twisted as it passes through the LC material If the front polarizer is oriented perpendicular to the rear polarizer, light will pass through the energized display but will be blocked by the rear polarizer. An LCD in this form is acting as a light shutter.
Displays with variable characters are created by selectively etching away the conductive surface that was originally deposited on the glass. Etched areas become the display’s background; unetched areas become the display’s characters.
V270W1- L03 is a 27” TFT Liquid Crystal Display module with 14-CCFL Backlight unit and 1ch-LVDS interface. This module supports 1280 x 720 WXGA format and can display true 16.7M colors ( 8-bit/color). The inverter module for backlight is build-in.
The lamp frequency may produce interference with horizontal synchronous frequency from the display, and this may cause line flow on the display. In order to avoid interference, the lamp
frequency should be detached from the horizontal synchronous frequency and its harmonics as far as possible.
Note (4) PL =(Σ lamp1-lamp14 IL ×VL )/0.8, PL is based on the inverter efficiency, which is 80%.
Note (5) The lifetime of a lamp is defined as the time in which it continues to operate under the condition Ta = 25 ±2 oC and IL = (4.35) ~ (4.95) mArms until one of the following events occurs:
(a) When the brightness becomes equal or less than 50% of its original value.
(b) When the effective discharge length becomes equal or less than 80% of its original value.
(Effective discharge length is defined as an area that has equal or more than 70% brightness compared to the brightness at the center point.)
Note: the waveform of the voltage output of inverter must be area-symmetric and the design of the inverter must have specifications for the modularized lamp. The performance of the Backlight, such as lifetime or brightness, is greatly influenced by the characteristics of the DC-AC inverter for the lamp. All the parameters of an inverter should be carefully designed to avoid producing too much current leakage from high voltage output of the inverter. When designing or ordering the inverter please make sure that a poor lighting caused by the mismatch of the Backlight and the inverter (miss-lighting, flicker, etc.) never occurs. If the above situation is confirmed, the module should be operated in the same manners when it is installed in your instrument.
frequency should be detached from the horizontal synchronous frequency and its harmonics as far as possible.
Note (4) PL =(Σ lamp1-lamp14 IL ×VL )/0.8, PL is based on the inverter efficiency, which is 80%.
Note (5) The lifetime of a lamp is defined as the time in which it continues to operate under the condition Ta = 25 ±2 oC and IL = (4.35) ~ (4.95) mArms until one of the following events occurs:
(a) When the brightness becomes equal or less than 50% of its original value.
(b) When the effective discharge length becomes equal or less than 80% of its original value.
(Effective discharge length is defined as an area that has equal or more than 70% brightness compared to the brightness at the center point.)
Note: the waveform of the voltage output of inverter must be area-symmetric and the design of the inverter must have specifications for the modularized lamp. The performance of the Backlight, such as lifetime or brightness, is greatly influenced by the characteristics of the DC-AC inverter for the lamp. All the parameters of an inverter should be carefully designed to avoid producing too much current leakage from high voltage output of the inverter. When designing or ordering the inverter please make sure that a poor lighting caused by the mismatch of the Backlight and the inverter (miss-lighting, flicker, etc.) never occurs. If the above situation is confirmed, the module should be operated in the same manners when it is installed in your instrument.
EEPROM
The AT24C01A/02/04/08/16 provides 1024/2048/4096/8192/16384 bits of serial electrically erasable and programmable read only memory (EEPROM) organized as 128/256/512/1024/2048 words of 8 bits each. The device is optimized for use in many industrial and commercial applications where low power and low voltage operation are essential. The AT24C01A/02/04/08/16 is available in space saving 8-pin PDIP, 8-pin and 14-pin SOIC packages and is accessed via a 2-wire serial interface. In addition, the entire family is available in 5.0V (4.5V to 5.5V), 2.7V (2.7V to 5.5V), 2.5V (2.5V to 5.5V) and 1.8V (1.8V to 5.5V) versions.
Pin Description
SERIAL CLOCK (SCL): The SCL input is used to positive edge clock data into each E2PROM device and negative edge clock data out of each device.
SERIAL DATA (SDA): The SDA pin is bidirectional for serial data transfer. This pin is open-drain driven and may be wire-ORed with any number of other open-drain or open collector devices.
DEVICE/PAGE ADDRESSES (A2, A1, A0): The A2, A1 and A0 pins are device address inputs that are hard wired for the AT24C01A and the AT24C02. As many as eight 1K/2K devices may be addressed on a single bus system (device addressing is discussed in detail under the Device Addressing section).
The AT24C04 uses the A2 and A1 inputs for hard wire addressing and a total of four 4K devices may be addressed on a single bus system. The A0 pin is a no connect.SERIAL DATA (SDA): The SDA pin is bidirectional for serial data transfer. This pin is open-drain driven and may be wire-ORed with any number of other open-drain or open collector devices.
DEVICE/PAGE ADDRESSES (A2, A1, A0): The A2, A1 and A0 pins are device address inputs that are hard wired for the AT24C01A and the AT24C02. As many as eight 1K/2K devices may be addressed on a single bus system (device addressing is discussed in detail under the Device Addressing section).
The AT24C08 only uses the A2 input for hardwire addressing and a total of two 8K devices may be addressed on a single bus system. The A0 and A1 pins are no connects.
The AT24C16 does not use the device address pins which limit the number of devices on a single bus to one. The A0, A1 and A2 pins are no connects.
V-Chip PasswordThe AT24C16 does not use the device address pins which limit the number of devices on a single bus to one. The A0, A1 and A2 pins are no connects.
> Omnipotence V-Chip Password: 8205.
> Press MENU button.
> Press LEFT RIGHT buttons to highlight "MISC" Menu.
> Press Up, Down buttons to highlight "Parentald".
> Press ENTER button to pop up "Input your Password Please".
> Use the Number buttons (0~9) to enter an omnipotence Password.
> Press ENTER button to confirm and your can select "CHANGE PASSWORD".
> Suggest: Change to your familiar Password again.
> Press MENU button.
> Press LEFT RIGHT buttons to highlight "MISC" Menu.
> Press Up, Down buttons to highlight "Parentald".
> Press ENTER button to pop up "Input your Password Please".
> Use the Number buttons (0~9) to enter an omnipotence Password.
> Press ENTER button to confirm and your can select "CHANGE PASSWORD".
> Suggest: Change to your familiar Password again.
Akai LCT2662 TFT LCD TV Picture in Picture – SMPS SCHEMATIC
Power:
1). Input voltage: AC 100V~240V, 47Hz~63Hz. Input range: AC 90V(Min)~264V(Max) auto regulation.
2). To provide power for PCBs.
a). +24V for Inverter.
b). +5Vsb for standby,
c). +5V for signal power,
d). +24V for Audio Amp power and converter to
e). +12V for Tuner power.
1). Input voltage: AC 100V~240V, 47Hz~63Hz. Input range: AC 90V(Min)~264V(Max) auto regulation.
2). To provide power for PCBs.
a). +24V for Inverter.
b). +5Vsb for standby,
c). +5V for signal power,
d). +24V for Audio Amp power and converter to
e). +12V for Tuner power.
1.The supply voltage of the external system for the module input should be the same as the definition of Vcc.
2. Apply the lamp voltage within the LCD operation range. When the backlight turns on before the LCD operation of the LCD turns off before the backlight turns off, the display may momentarily become abnormal screen.
3. In case of VCC = off level, please keep the level of input signals on the low or keep a high impedance.
4. T4 should be measured after the module has been fully discharged between power of and on period.
5. Interface signal shall not be kept at high impedance when the power is on.
2. Apply the lamp voltage within the LCD operation range. When the backlight turns on before the LCD operation of the LCD turns off before the backlight turns off, the display may momentarily become abnormal screen.
3. In case of VCC = off level, please keep the level of input signals on the low or keep a high impedance.
4. T4 should be measured after the module has been fully discharged between power of and on period.
5. Interface signal shall not be kept at high impedance when the power is on.
COLOR DATA INPUT ASSIGNMENT
The brightness of each primary color (red, green and blue) is based on the 8-bit gray scale data input for the color. The higher the binary input, the brighter the color. The table below provides the assignment of color versus data input.
LVDS interface
TFT LCD MODULE INPUT TERMINAL PIN ASSIGNMENT
Software upgrade
> Connect the RS-232C input jack to an external control device (such as a computer) and software upgrade.
> Power Switch OFF.> Connect the RS-232C input jack to an external control device (such as a computer) and software upgrade.
> Connect the serial port of the control device to the RS-232 jack on the LCD-TV back panel.
RS-232C connection cables are not supplied with the LCD-TV.
> Power Switch ON. The power indicator on the front of the panel should now display red, means that the LCD-TV is in standby mode.
> Copy the software (MTKTOOL) to the computer.
> Open the software (MTKTOOL.EXE)
> Select MTK 8205 and Point "browse" on the interface of the MTKTOOL.exe.
> Select the file which will be update.
> Point "update" on the interface of the MTKTOOL.exe.
> Waiting for the upgrader programing, when it is finished, the bar will display 100%.
> After the upgrader is finished, shut down the power switch, take out the RS-232C connection after the power indicator is extinguished.
Note: After upgrading, the first time of power on will be some long.
RS-232C connection cables are not supplied with the LCD-TV.
> Power Switch ON. The power indicator on the front of the panel should now display red, means that the LCD-TV is in standby mode.
> Copy the software (MTKTOOL) to the computer.
> Open the software (MTKTOOL.EXE)
> Select MTK 8205 and Point "browse" on the interface of the MTKTOOL.exe.
> Select the file which will be update.
> Point "update" on the interface of the MTKTOOL.exe.
> Waiting for the upgrader programing, when it is finished, the bar will display 100%.
> After the upgrader is finished, shut down the power switch, take out the RS-232C connection after the power indicator is extinguished.
Note: After upgrading, the first time of power on will be some long.
Universal remote control set-up code list
0049 0050 0055 0066 0076 0102 0107 0110 0123 0141 0150 0039 0101 0152 0182 0195 0209 0225 0379 0428 0433 0437 0119 0166 0181 0214 0222 0231 0235 0247 0460 0465 0601 0611 0618 0622 0631 0633 0638 0649 0655 0669 0672 0673 0734 0792 0810 0813
Programming Notes
• If your device does not respond to the remote after trying all codes listed or your brand is not listed in the code list, use the Auto Code Search method to program your remote.
• Sometimes the first code that “works” with your device may operate only a few functions of your device. There may be another code in the code list that performs more functions. Try other codes from the code list for more functionality.
• Sometimes the first code that “works” with your device may operate only a few functions of your device. There may be another code in the code list that performs more functions. Try other codes from the code list for more functionality.
This is a trial and error procedure; and quiet time consuming. You might have to check different codes said for your device.