JPH0563162U - Horizontal deflection linearity correction circuit - Google Patents

Abstract

(57) [Abstract] [Purpose] By controlling the inductance of the secondary side by the current flowing in the primary side of the choke transformer, the inductance required for correction due to the secondary resonance of the horizontal deflection circuit is controlled for all horizontal deflection frequencies. Then, linearity correction of horizontal deflection by the secondary resonance wave is continuously performed. [Structure] Horizontal output transformer 1, horizontal output transistor 2, damper diode 3, resonance capacitor 4, horizontal deflection coil 5, S-shaped correction capacitor 6, first secondary resonance capacitor 7, choke transformer 8, second 2 The next resonance capacitor 9, the choke transformer drive circuit 10, and the control circuit 11 constitute a horizontal deflection linearity correction circuit.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a horizontal deflection linearity correction circuit suitable for use in a horizontal deflection device for a multi-scan television receiver.

[0002]

[Prior Art]

 Conventionally, this type of linearity correction circuit has a configuration as shown in FIG. In the figure, 1 is a horizontal output transformer, 2 is a horizontal output transistor, 3 is a damper diode, 4 is a resonant capacitor, 5 is a horizontal deflection coil, 6 is an S-correction capacitor, and 7 is a first secondary resonant capacitor. , 8 is a secondary resonance coil, 9 is a second secondary resonance capacitor, and 18 is a + B power supply input terminal.

The circuit operation will be described below.

In the figure, except for a _first secondary resonance capacitor 7 (hereinafter C ₁ ), a secondary resonance coil 8 (hereinafter L ₁ ), and a second secondary resonance coil 9 (hereinafter C ₂ ). For example, a general horizontal deflection circuit. The resonance frequencies of C ₁ , C ₂ and L ₁ are set around a frequency twice the horizontal deflection frequency, and the secondary resonance wave is superimposed on the primary resonance wave as shown in FIG.

The resonance frequencies of C ₁ , C ₂ and L ₁ are expressed by the following equation (1).

[0006]

[Formula 1]

The amount of the secondary resonance wave superimposed on the primary resonance wave changes depending on the difference between the frequency twice the horizontal deflection frequency and the resonance frequencies of C ₁ , C ₂ , and L ₁ . This is because the resonance caused by C ₁ , C ₂ , and L ₁ has Q.

By the composite wave of the primary resonance and the secondary resonance obtained as described above, the linearity when only the primary resonance shown in FIG. 4A is corrected as shown in FIG. 4B. R.

[0009]

[Problems to be solved by the device]

 In the conventional linearity correction circuit based on the secondary resonance of the horizontal deflection, the values of the first secondary resonance capacitor, the second secondary resonance capacitor, and the secondary resonance coil are fixed. There is a drawback that the ideal linearity correction can be performed only for the horizontal deflection frequency.

Further, by switching between the first secondary resonance capacitor, the second secondary resonance capacitor, and the coil for secondary resonance, ideal linearity correction for a plurality of horizontal deflection frequencies is performed. This can be done, but switching circuits such as relays are required for the number of horizontal deflection frequencies to be handled.

Therefore, an object of the present invention is to provide a linearity correction circuit using secondary resonance of ideal horizontal deflection for all horizontal deflection frequencies by using a secondary resonance coil having a variable inductance. Especially.

[0012]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention provides a horizontal output transformer, a horizontal output transistor connected in series to the horizontal output transformer, a damper diode connected in parallel to the horizontal output transistor, and a parallel circuit of a resonant capacitor. A series circuit of a horizontal deflection coil and an S-correction capacitor connected in parallel to the horizontal output transistor, a first secondary resonance capacitor and a second secondary resonance capacitor connected in parallel to the S-correction capacitor. Of the series circuit, the secondary side of the choke transformer connected in parallel with the first secondary resonance capacitor, the drive circuit for flowing the control current to the primary side of the choke transformer, and the drive circuit to the horizontal deflection frequency. A horizontal deflection linearity correction circuit having a control circuit for controlling correspondingly.

[0013]

[Action]

According to this invention, the resonance frequency of the secondary resonance circuit including the first secondary resonance capacitor (7), the second secondary resonance capacitor (9), and the choke transformer (8) is different from that of the horizontal resonance circuit. There is one value for each of the optimum corrections to the deflection frequency, but the optimum resonance frequency is derived by changing the secondary inductance (L ₁ ) of the choke coil (8). Yes, the secondary side inductance (L ₁ ) of the choke coil (8) is variable by controlling the current flowing through the primary side winding (L ₂ ) of the choke coil (8) by the control circuit (10). Of. A voltage corresponding to the horizontal deflection frequency is applied to the control circuit (10), and as a result, an optimal secondary resonance wave is obtained for any horizontal deflection frequency, and ideal linear deflection linear correction is performed. You can

[0014]

【Example】

 Next, an embodiment of the present invention will be described with reference to FIGS. 1, 3 and 4.

In FIG. 1, 1 is a horizontal output transformer, 2 is a horizontal output transistor, 3 is a damper diode, 4 is a resonance capacitor, 5 is a horizontal deflection coil, 6 is an S-shaped correction capacitor, and 7 is a first capacitor. Secondary resonance capacitor, 8 is a secondary resonance choke transformer, 9 is a second secondary resonance capacitor, 10 is a choke transformer drive circuit, 11 is a drive circuit control circuit, 12 is a frequency-voltage conversion circuit, 13 is a limiter circuit, 14 is a buffer amplifier, 15 is a voltage controlled variable frequency oscillator (VCO), 16 is a horizontal output transistor drive circuit, 17 is an AFC circuit, 18 is a + B power supply input terminal, 19 is a drive power supply. It is an input terminal.

Next, the operation will be described.

The horizontal period signal is input to the frequency-voltage conversion circuit (12), and a voltage is formed according to the horizontal frequency. As the frequency-voltage converter circuit (12), for example, a horizontal synchronizing signal is supplied to a mono-multivibrator having a predetermined time constant, an output signal of this mono-multivibrator is supplied to a smoothing low-pass filter, and an output terminal is provided. The voltage corresponding to the horizontal frequency is obtained. This voltage is supplied to the VCO (15) through the limiter circuit (13) that defines the lower limit and the buffer amplifier (14). The oscillation output of the VCO (15) is supplied to the horizontal output transistor (2) for switching through the drive circuit (16).

A horizontal cycle signal is supplied to the AFC circuit (17), and a pulse generated on the secondary side of the horizontal output transformer (1) is supplied to the AFC circuit (17). The signal from 17) is supplied to the control terminal of VCO (15).

Further, a voltage corresponding to the frequency from the frequency-to-voltage conversion circuit (12) is supplied to the choke transformer control circuit (11), the control circuit performs arithmetic processing, and the calculated voltage is choked. It is supplied to the drive circuit (10) of the transformer (8). A current according to this voltage flows in the primary winding of the choke transformer (8), and the current provides a secondary inductance (L ₁ ) of the choke transformer (8) according to the horizontal frequency.

The secondary side inductance (L ₁ ) of the choke transformer (8), the capacitance (C ₁ ) of the first secondary resonance capacitor (7), and the second secondary resonance capacitor (9) With the capacitance (C ₂ ), the secondary resonance wave of the resonance frequency obtained by the calculation formula shown in the equation (1) is converted into the inductance of the horizontal deflection coil (5) and the capacitance of the S-shaped correction capacitor (6). As shown in FIG. 4 (a), the linearity is superimposed on the primary resonance wave of FIG. 3 and corrected only by the primary resonance shown in FIG. 4 (a). That is, for various horizontal deflection frequencies, the secondary side inductance (L ₁ ) of the choke transformer (8) required for correction by the secondary resonance wave is determined _one by one, and the control circuit (11 The linearity correction of the horizontal deflection can be performed by performing the calculation in ().

The present invention is not limited to the above-described embodiments, but can be variously modified without departing from the gist of the present invention.

[0022]

[Effect of the device]

 As described above, according to the present invention, the inductance required for correction due to the secondary resonance of the horizontal deflection circuit is obtained from the choke transformer that controls the inductance of the secondary side by the current flowing to the primary side, thus saving space. This has the effect that the linearity correction of the horizontal deflection by the secondary resonance wave can be continuously performed for all horizontal deflection frequencies.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a horizontal deflection linearity correction circuit according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of a conventional horizontal deflection linearity correction circuit.

FIG. 3 is a voltage waveform diagram across an S-shaped correction capacitor.

FIG. 4 is a linearity characteristic diagram of horizontal deflection.

[Explanation of symbols]

 1 Horizontal Output Transformer 2 Horizontal Output Transistor 3 Damper Diode 4 Resonant Capacitor 5 Horizontal Deflection Coil 6 S-Shape Correction Capacitor 7 First Secondary Resonant Capacitor 8 Choke Transformer 9 Second Secondary Resonant Capacitor 10 Choke Transformer Drive Circuit 11 Control circuit

Claims (1)

[Scope of utility model registration request] 1. A horizontal output transformer, a horizontal output transistor connected in series to the horizontal output transformer, a damper diode connected in parallel to the horizontal output transistor, a parallel circuit of a resonance capacitor, and a parallel circuit connected to the horizontal output transistor. A series circuit of a horizontal deflection coil and an S-correction capacitor connected to each other; a series circuit of a first secondary resonance capacitor and a second secondary resonance capacitor connected in parallel to the S-correction capacitor; The secondary side of the choke transformer connected in parallel to the secondary resonance capacitor of 1,
A horizontal deflection linearity correction circuit comprising: a drive circuit for supplying a control current to the primary side of the choke transformer; and a control circuit for controlling the drive circuit in accordance with a horizontal deflection frequency.