Part Number : TDA3653, TDA3653B, TDA3653C
Function : Vertical deflection and guard circuit, The TDA3653B/C is a vertical deflection output circuit for drive of various deflection systems with currents up to 1.5 A peak-to-peak.
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Features
1. Driver
2. Output stage
3. Thermal protection and output stage protection
4. Flyback generator
5. Voltage stabilizer
6. Guard circuit
FUNCTIONAL DESCRIPTION
1. Output stage and protection circuit
Pin 5 is the output pin. The supply for the output stage is fed to pin 6 and the output stage ground is connected to pin 4. The output transistors of the class-B output stage can each deliver 0.75 A maximum. The maximum voltage for pin 5 and 6 is 60 V. The output power transistors are protected such that their operation remains within the SOAR area. This is achieved by the co-operation of the thermal protection circuit, the current-voltage detector, the short-circuit protection and the special measures in the internal circuit layout.
2.Driver and switching circuit
Pin 1 is the input for the driver of the output stage. The signal at pin 1 is also applied via external resistors to pin 3 which is the input of a switching circuit. When the flyback starts, this switching circuit rapidly turns off the lower output stage and so limits the turn-off dissipation. It also allows a quick start of the flyback generator. External connection of pin 1 to pin 3 allows for applications in which the pins are driven separately.
3. Guard circuit
When there is no deflection current and the flyback generator is not activated, the voltage at pin 8 reduces to less than
1.8 V. The guard circuit will then produce a DC voltage at pin 7, which can be used to blank the picture tube and thus
prevent screen damage.
4. Voltage stabilizer
The internal voltage stabilizer provides a stabilized supply of 6 V to drive the output stage, which prevents the drive
current of the output stage being affected by supply voltage variations.
TDA3653 datasheet, TDA3653B datasheet, TDA3653C datasheet : [ TDA3653B ]
