Akira 14BM18 CTV – how to enter service mode, circuit diagram - TDA-935X - STR-G5653

Used ICs: TDA7056B, TDA8356, AT24C08, BSC60H2(FBT), STR-G5653(SMPS control)

Many electrical and mechanical components in this chassis have special safety-related characteristics. Components which have these special safety characteristics in this manual and its supplements are identified by the international hazard symbols or UL, FCC, FDA or VDE marking on the circuit diagram and parts list. When replacing any of these components, substitute the one which has the same safety characteristics.

Difference between STR-G5653 and STR-F6654

a. Different size: STR- F6654 is larger
b. Different pin functions
c. Different electric characteristics: Larger power output, switching current, avalanche-rated and internal allowable power consumption for STR-F6654
d. internal allowable power consumption for STR-F6654.

Switch-mode Power Supply STR- G5653/F6654
The Series STR-G5653/F6654 is specifically designed to satisfy the requirements for increased integration and reliability in off-line quasi-resonant fly-back converters. The series incorporates a high-precise error amplifying control and drive circuit with discrete avalanche-rated power MOSFET,
featuring fewer external components, small-size and standard power supply.
Covering the power range from below 25 watts up to 300 watts for 100/115/230 VAC inputs, and up to 150 watts for 85 to 265 VAC universal input, these devices can be used in a range of applications, from battery chargers and set top boxes, to televisions, monitors, and industrial power supply units.  Cycle-by-cycle current limiting, under-voltage lockout with hysteresis, over-voltage protection, and thermal shutdown protects the power supply during the normal overload and fault conditions.
Low-current startup and a low-power standby mode selected from the secondary circuit completes a comprehensive suite of features. The series is provided in a five-pin over-molded SIP style package, affording dielectric isolation without compromising thermal characteristics.
Features
Fly-back Operation with Quasi-Resonant Soft Switching for Low Power Dissipation and EMI Rugged Avalanche-Rated MOSFET
Soft drive circuit MOSFET
Adjustable MOSFET switching speed
Choice of MOSFET Voltage and rDS(on)
Full Over-Current Protection (no blanking)
Under-Voltage Lockout with Hysteresis
Over-Voltage Protection
Direct Voltage Feedback
Low Start-up Current (100 Amax)
Low-Frequency, Low-Power Standby Operation
Over molded 5-Pin Package

SMPS schematic (STR-G5653)

EEPROM AT24C08: Features

Data EEPROM internally organized as 1024/2048 bytes and 64/128 pages×16 bytes

Page protection mode, flexible page-by-page hardware write protection

Additional protection EEPROM of 64/128 bits, bit per data page

1-Protection setting for each data page by writing its protection bit

Protection management without switching WP pin Low power CMOS

Vcc=2.7 to 5.5V operation.

Two wire serial interface bus, I2C-Bus compatible Filtered inputs for noise suppression with Schmitt trigger

Clock frequency up to 400 kHz

High programming flexibility

Internal programming voltage.

Self timed programming cycle including erase

Byte-write and page-write programming, between 1 and 16 bytes

Typical programming time 6ms(<10ms) for up to 16 bytes

High reliability

Endurance 106 cycles1)

Data retention 40 years1)

ESD protection 4000 V on all pins

8 pin DIP/DSO packages.

DC-coupled vertical deflection circuit TDA8356
Features
Few external components
Highly efficient fully DC-coupled vertical output bridge circuit
Vertical flyback switch
Guard circuit
Protection against:
Short-circuit of the output pins (7 and 4)
Short-circuit of the output pins to VP.
Temperature protection
High EMC immunity because of common mode inputs
A guard signal in zoom mode.
General Description
The TDA8356 is a power circuit for use in 90, and 110, colour deflection systems for field frequencies of 50 to 120 Hz. The circuit provides a DC driven vertical deflection output circuit, operating as a highly efficient class G system.

14BM18 uses mainly Philips’ advanced UOC-ultimate chip TDA935X/6X/8X and I2C-bus controlled IC. With combination of microcontroller and small signal processor, the TDA935X/6X/8X series feature high-integration, high-performance-to-price ratio and high-reliability and advanced functions with fewer external components, which provide much convenience for manufacturing and technical service.

Microcontroller and small signal processor TDA935X/6X/8X

The super chips TDA935X/6X/8X are good in pins compatibility. Differences among them are shown as follows.

TDA9351 48K PAL/NTSC/SECAM+1 PAGE TELETEST

TDA9350 48K PAL/NTSC+1 PAGE TELETEST

TDA9361 64K PAL/NTSC/SECAM+10 PAGE TELETEST

TDA9360 64K PAL/NTSC+10 PAGE TELETEST

TDA9380 32K PAL/NTSC

TDA9387 32K NTSC

TDA935X/6X/8X PS/N2 series TV signal processor-Teletext decoder with embedded Controller

General Description

The various versions of theTDA935X/6X/8X PS/N2 series combine the functions of a TV signal processor together with a ¬-Controller and US Closed Caption decoder. Most versions have a Teletext decoder on board. 

The Teletext decoder has an internal RAM memory for 1or 10 page text.

The ICs are intended to be used in economy television receivers with 90 and 110 picture tubes.

The ICs have supply voltages of 8 V and 3.3 V and they are mounted in S-DIP envelope with 64 pins.

Schematic (Full)

Click on the pictures to magnify

5W Mono BTL Audio Amplifier with DC Volume Control TDA7056B

The TDA7056B is a mono Bridge-Tied Load (BTL) output amplifier with DC volume control.
It is designed for use in TV and monitors, but is also suitable for battery-fed portable recorders and radios.  The device is contained in a 9-pin medium power package.
A Missing Current Limiter (MCL) is built in. The MCL circuit is activated when the difference in current between the output terminal of each amplifier exceeds 100 mA (300 mA type). This level of 100 mA allows for headphone applications (single-ended).
Features
DC volume control
Few external components
Mute mode
Thermal protection
Short-circuit proof
No switch-on and switch-off clicks
Good overall stability
Low power consumption
Low HF radiation
ESD protected on all pins.

DESIGN or SERVICE mode
To enter the USER SERVICE mode:
Caution: The user service mode adjustment can be changed only when service personnel adjust the whole set data during servicing. As the control data have dramatic effects on functions and performance of the TV, service personnel should not tell user how to enter the SERVICE mode to avoid improper data settings.
Set the volume to 0. Then press and hold the MUTE button on the remote control, and press the MENU button on the TV to enter the SERVICE mode.

(In this case, the S mode cannot be stored in the EEPROM. To exit from the S mode, turn off the TV set. )
After entering the S mode, Red S is displayed on the upper center of the screen and MENU1 is default. 

Use the POS+/- buttons to highlight an adjustment and the VOL+/- buttons to adjust it. 

The adjusted data are immediately output and stored in the EEPROM.

With remote control system software TDA935X, all options can be set in the SERVICE mode and stored in EEPROM. Data related to picture, sound and geometric adjustment are also stored in EEPROM

Supply Voltage Adjustment
Caution: +B voltage has close relation to high voltage. To prevent X-ray radiation, set +B voltage to the rated voltage.
Make sure that the supply voltage is within the range of the rated value.
Connect a digital voltmeter to the +B voltage output terminal of the TV set. Power on the TV and set the brightness and sub-brightness to minimum.
Regulate voltage adjustment components on the power PCB to make the voltmeter read 115±1V.