PROTEK / SHARP SENSOR ON TV
Recall the author, since the first, sharp tv products are equipped with protection system. If found irregularities / abnormalities, tv will protectionism by itself (for the security of the device / user). And now, almost all tv brands were also using the system of protection. But when compared with the protection belongs sharp tv, no equal. Therefore, the authors do not be surprised if a scourge for tv sharp tv repair shop.
Almost all states / tv sharp blocks equipped with sensors protectionism by type and different methods, among others:
1. Sensor Voltage: v heater, 115V B +, B + vertical, 12/16V and other stresses. Overvoltage protection consists of voltage and NoVoltage. The components used for voltage sensors typically use a diode (zener / diode usual - 1N4148).
2. Sensor Output / input blocks: vertical output (Vertical Guard), H sync, etc.. TV will be protectionist if no output / signal or voltage output in the form of DC.
3. Sensor Sync: although rare, this protection is usually already included in the jungle IC / chroma.
4. X-ray protection: ABL voltage censor, serves to censor the HV voltage (since the ABL is minus HV).
5. and most recently, digital data protection. Because the circuit is designed sekompak / as possible (used in 1 chip), the protection system is also incorporated into the IC. IC-ic it will send data to the IC-program if the system (in these ic) there was something wrong, then ic program will protect the on / off the tv device.
BOOT UP AND SELF TEST
The author will try to explain the bootup sequence. Bootup is the stages of the operation of television, from the dead to operate normally. Do not be surprised if the chassis tv sharp rise TDA93xx taking pictures for a while ...., because ic-muter muter program first (cool SelfTest ).
Stages of self-test ( correction please ) as follows:
1. Regulators operate well -> the standby voltage (3.3 V), crystal oscillator on-ic works program to give a pulse / clock ic program.
2. Program reset, reset is controlled by the reset IC (PST573, the Goldstar / other brands KIA70), on pin 60.
3. After reset, the program to load / read the EEPROM (retrieve data service). If it fails to read / load -> protectionism.
4. After reading the EEPROM, the program will try to turn on the TV (power on), beginning with the turn on the regulator to position ON (B + 115V full), followed by the operation of osc jungle (horizontal and vertical). For a while, the video signal in a state of MUTE.
5. After the flyback transformer works, ic programs (with the help of the zener, diode-diode), censoring / check stresses vital. If found abnormal, tv will protectionism.
6. Checking process is followed by checking the voltage input / output amplification (vertical out, X-rays, etc.).
7. The next step is checking the signal / sync, the video signal entered and processed (at present, the output to the tube / video drive is still on MUTE -> no picture / raster), the aim is to detect and ensure that osc Vert hor and synchronized by the video / raster. If sync fails, tv will protectionism.
8. Checking digital / data service. Previously, the tv is turned on based on settings stored in the data service (EEPROM), if the data can not be set, the tv will protectionism. for example. NICAM data set at 1 (NICAM = 1) when the series / tv series there were no NICAM, tv will protectionism. This stage is the stage of checking the digital data (internally).
9. Checking external digital (peripherals, outside IC), the program will check the existence of additional peripheral/alat2 outside the IC through the data bus (SDA and SCL, using I2C protocol), then set the equipment in accordance with the data stored in EEPROM. In sharp Wonder, peripherals / external equipment such as: Tuner (PLL), AN5891K (SoundProcessor) and M52797SP (AV switch), if the communication to / from external perangkat2 failed / interrupted, the tv will protectionism.
10. When everything goes wrong, the video signal in unmuted (shown).
11. During the operation, ic program to constantly monitor all the doors of protection.
For stage 5 and 6 above, using a pin protectionism that is pin 8 (normally About a 3.2 v) at IX3386 and IX3410.
To find out where the error / protectionism occurs, plant equip Sharp tvnya product with blink code. Blink code can be known from the long / short and the number of blinking LED indicator lights. Rather than measuring the length of dizziness / short blink, more easily counted only the number kedipannya. Blink code indicated by:
1. LED blink code using red, green if the flashing might not blink code.
2. As an illustration ( use your imagination ), flashing code 4 will be shown as follows: LED lamp lights up 4 times (the length of each light kira2 200ms - kira2 second quarter - ), then a pause / off kira2 half a second (400ms) - lit / blinking again 4 times -> pause / off kira2 half a second (400ms) -> blink again 4 times ........ so on.
While the types kedipnya code along with the type of damage as follows ( based on the author's experience ), as follows:
* Blink 1 times: bus error data may be due to failure in reading program memory or data bus (SDA, SCL).
* Blink 3 times: Jungle (osc horizontal, vertical), can also be caused by x-ray (ABL).
* Blinking 4 times: Synchronization failed, video / raster is not detected, VIF. AV Switch noteworthy.
* Blink 6 times: Internal peripheral, nicam, SIF. Due to the data service that is not appropriate.
* Blinking 7 times: internal settings, signal format, setting decoder. Due to the data service that is not appropriate.
* Blink 8 times: Tuner (failed to set the tuner or tuner frequency is not detected), can also be caused by external peripherals (eg AN5891K, M52797SP) because the bus disrupted.
note: for dips 2 and 5 (or blink), the author has never encountered ( if any have ever come across please contribution ).
THIS REPAIR TIPS chassis
1. If the tv is turned red immediately (without blinking), check transformer FB, stresses the vital, R625 (SMD) worth 180K, from the 180V line.
2. If blinking 1 to 4, the steps: operating all solderan, if necessary re-soldered. More-more on R and C SMD under Vertical ic. If not effective, there are components that are damaged around a series of Jungle, the pins that need to be checked: pin 21 (Vdrive A), pin 22 (VdriveB), pin 33 along with a series of hormonal drives. Stresses the vital need to also be checked.
3. If you blink 4 or more, just go to service mode. TV will turn on and had time to check voltages. If need to change the service mode settings. (Write once setting first, before making any changes).
4. If a blink code changes, for example, when turned on flashes 8 times then turned off, turned on again it turns out kedipnya turned into 4 times, which need to be checked are the data bus lines (SDA, SCL). In Wonder, check two 5V zener (D302, D303) located close to the AN5891.
5. Before you intend to soldering, you should first check the data service modes.
6. By understanding the stages of Self Test, it's easier to know the location of the damage.
Good luck ... add your own risk severely damaged hehehe ..