SU1319315A1 - Output stage of horizontal-scanning generator - Google Patents

Abstract

The invention relates to television and provides improved speed and reduced mosh.nost losses. The output stage of the horizontal sweep generator contains transistors (T) 1, 8, damping diode 2, backward capacitor 3, deflection, 4 coil, S-correction capacitor 5, horizontal transformer 6, diodes 7, 9, 13, integrated capacitor 10, resistors 11, 14, matching transformer (CT) 12. The primary winding of transformer 6 plays the role of power droplets. T 1 is controlled by voltage pulses arriving at its base from the second secondary winding CT 12. Resistor 14 is designed to change the time T 1 turns on, and its shunt diode 13 ensures the flow of a reverse base current caused by the locking voltage on the second secondary winding CT 12. To form a sawtooth current, it flows through the deflecting coil 4. T 1, under the action of control pulses, is unlocked for the forward running time and locked for the reverse travel time. 2 Il. tc (L oo QD CO Oi Figure 1

Description

This invention relates to a television technique and can be used in horizontal-line generators.

The purpose of the invention is to increase speed and reduce power loss.

FIG. Figure 1 shows the electrical circuit diagram of the horizontal output generator stage; in fig. 2 - timing diagrams illustrating the operation of the output stage generator line scan.

The output stage of the horizontal sweep generator contains the first transistor 1, between the collector and the emitter of which are connected in parallel the damper diode 2, the reverse capacitor 3 and the deflector 4 in series and the S-correction capacitor 5 connected in series. The damper diode is connected to the collector of the first transistor 1 by its cathode. In addition, the collector of the first transistor 1 is connected to the first terminal of the primary winding of a line transformer 6, the second terminal of which is a voltage input from the first power source. The first output of the secondary winding of the horizontal transformer 6 is connected to the cathode of the first additional diode 7 and to the collector of the second transistor 8, the emitter of which is connected to the anode of the second additional diode 9, the cathode of which is connected to the collector of the first transistor 1. The second output of the secondary winding of the horizontal transformer is the positive input voltage from a second power source. The base of the second transistor 8 is connected to the first output of the integrating capacitor 10 and through the first resistor 11 to the first output of the first secondary winding of the matching transformer 12. The emitter of the second transistor 8 is connected to the second output of the integrating capacitor 10 and to the second output of the first secondary winding of the matching transformer 12. First the output of the second secondary winding of the matching transformer 12 is connected to the anode of the first additional diode 7, to the base of the first transistor 1 and is a negative voltage input From a second power source. The second terminal of the second secondary winding of the matching transformer 12 is connected to the anode of the third additional diode 13 and through the second resistor 14 to the cathode of the third additional diode 13 and to the emitter of the first transistor 1. The outputs of the primary winding of the matching transformer 12 are the input of synchronization pulses.

The output stage generator horizontal scan works as follows.

The primary winding of the transformer 6 performs the role of power droplets. The first transistor 1 is controlled by voltage pulses arriving at its base from the secondary winding of the matching transformer 12. The second resistor 14 is designed to change the turn-on time of the first transistor 1, and the bypass switch it the third

An additional diode 13 provides for the flow of a reverse base current pulse, due to the blocking voltage on the second secondary winding of the matching transformer 12. To form

The current of the sawtooth shape (Fig. 2c) flowing through the deflecting coil 4, the first transistor 1 under the action of the control pulses is unlocked for the time of the forward stroke and locked to. return time. Matching transformer 12

5 has a first secondary winding connected in phase with the second secondary winding (Fig. 2a, b). Using an integrating RC circuit consisting of the first resistor 11 and the integrating capacitor 10, a voltage pulse is generated (Fig. 2a) on

0 the base-emitter junction of the second transistor 8. During the time of the triggering pulse, the integrating capacitor 10 is recharged from voltage to - (- UB-T (Fig. 2e). At the end of the forward stroke at time

5 ti, the second transistor 8 opens in the circuit formed by the voltage source EI, the secondary winding of the horizontal transformer 6, the second transistor 8, the second additional diode 9 and the collector-base transition of the first transistor 1,

0 a current pulse i begins to flow: (Fig. 2g). From this point in time, the resorption process begins, which ends at the time point tg, after which the collector current of the first transistor 1 begins to decrease (Fig. 2d). In the circuit,

5 formed by the inductance of the deflecting coil 4 and the reverse capacitor 3, due to the energy accumulated during the forward stroke in the inductance of the deflecting coil 4 of the energy, an oscillatory process occurs due to which a voltage pulse of a long-sided voltage is generated on the collector of the first transistor 1 (Fig 2d), locking the second additional diode 9, which disconnects the collector-base junction of the first transistor 1 from the forcing circuit. A voltage pulse is induced in the secondary winding of the horizontal transformer 6, which opens the first additional diode 7. The current in the collector circuit of the second transistor 8 changes its direction (Fig. 2g) and with a certain direction of switching on the primary and secondary windings of the horizontal transformer 6 affects the circuit primary winding so that the decline of the collector current of the first transistor 1 is accelerated. At the end of the half-period of natural oscillations in the circuit, the deflection of the coil 4 is reversed - the reverse-side capacitor 3 is unlocked by the damper diode 2, which bypasses the oscillating circuit. The deflection coil 4 begins to flow the current of the first half of the forward stroke of the sweep t4-1z (Fig. 2c), during which the energy stored in the inductance of the deflection coil 4 returns to the power supply + EK. At time t4, the first transistor 1 is unlocked and the second half of the forward sweep begins, during which the energy coming from the source - {- Ek, accumulates in the inductance of the deflecting coil 4. At the time ts, the base of the first transistor I receives a pulse the locking voltage and after the final stage of resorption of the minority carriers, te-ts, the collector current decrease and the sweep sweep start. The capacitor 5 S-correction eliminates the flow of the constant component of the current through the deflecting coil 4 and allows you to obtain the necessary S-shape pulses of the deflecting current.

In this way, both the turn-off time and the resorption time are reduced, which means an increase in speed and a decrease in power loss when locking the first transistor 1.

Claims (1)

Invention Formula The output stage of the horizontal sweep generator containing the first transistor, to the collector of which the cathode of the damping diode is connected, and to the emitter its anode, parallel to the damping diode, the reverse capacitor and the deflection coil connected in series and the S-correction capacitor, the collector of the first transistor co0 It is also connected to the first terminal of the primary winding of a line transformer, the second terminal of which is the voltage input of the first power source, the second transistor whose collector is connected to the cathode of the first additional diode and the first terminal of the secondary winding of the horizontal transformer, the second terminal of which is input the positive voltage of the second power source, the anode of the first additional diode is the input of the negative voltage of the second power source, the second additional diode, the anode of the connected to an emitter of the second transistor, characterized in that, 5 to improve performance and reduce power loss, a matching transformer, a first resistor, an integrating capacitor, a second resistor and a third additional diode are inserted, the terminals of the primary winding of the matching transformer are the input of synchronization pulses, the first terminal of the first secondary winding of the matching transformer is connected through the first resistor with the base of the second transistor and with the first output 5 integrating capacitor, the second output of which is connected to the emitter of the second transistor and the second output of the first secondary winding of the matching transformer, the first output of the second secondary winding of which is connected to the anode of the first additional diode and the base of the first transistor, and the second output - to the anode of the third additional diode, whose cathode is connected to the emitter of the first transistor, a second resistor is connected in parallel with the third additional diode. 0