JPS5810969A - Television receiver - Google Patents

Abstract

PURPOSE:To obtain a stable horizontal deflection without using a stabilized power supply, by providing a deflection current compensating means controlling the deflection current and the amplitude of horizontal collector pulse to a constant value and a pulse voltage compensating means for a horizontal deflection circuit. CONSTITUTION:An unstabilized voltage VA of an output of a power supply rectifying circuit 2 is applied to a horizontal deflection circuit via a primary winding L1 of a flyback transformer T1. A diode modulator 7 even with the voltage VA controls a deflection current flowing to deflection yoke L2 by controlling a voltage Vm across a capacitor C5. A current control circuit 8 changes the inductance of a secondary winding L5 by controlling the current supplied to a primary winding L6 of a transformer T2 in response to the voltage VA. A current detection circuit 9 controls the Vm to keep the deflection current constant in response to the VA.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power supply circuit for a television receiver, and its purpose is to reduce the power consumption of a television receiver by replacing a conventionally used stabilizing circuit. A conventional example is shown in Figure 1, where (l) is the power plug% (2) is the current flow circuit (2) is the stabilization circuit, and the power supply rectifier circuit (2) output. The unstabilized voltage V is stabilized to output a stabilized voltage v3. The stabilizing voltage Vs of C is applied to the east primary winding L1 of the flyback transformer, and the deflection current flows through the deflection yoke L1.scl is the resonance capacitor j1.ct is the figure-8 correction capacitor, Dl is the damper diode, and %Qt is the horizontal The output transistor (4) is a horizontal oscillation circuit and a horizontal drive circuit, which outputs a square wave pulse P that switches the horizontal output transistor Q1.

When a deflection current is passed through the deflection yoke L in the horizontal deflection circuit described above, a high half-1M period sine wave pulse is generated at the collector of the horizontal output transistor Q1. The output pulse (horizontal collector pulse) of this horizontal deflection circuit generates a higher pulse in the high-voltage fine secondary winding R1 of the flyback transformer TI, which is caused by the diode D1 and the capacitor CsC, which is actually the capacitor of the CRT. ) is rectified and smoothed and applied as high voltage to the CRT (5).

Further, the pulse generated in the low voltage side secondary winding L4 is transmitted through the diode D3. The voltage is rectified and smoothed by the capacitor C4, and then applied as a drive voltage to other signal circuits (@). Here, the stabilization circuit (3) always applies a constant voltage Vs to the horizontal deflection circuit even when the commercial power supply voltage fluctuates, so that the horizontal deflection circuit output pulse has a stable amplitude regardless of the fluctuation of the commercial power supply voltage. It's working like that.

However, for the stability limit M(3), a series control path using, for example, a transistor is used, but it has a very large loss and increases the power consumption of the television receiver.

Therefore, in order to avoid the above-mentioned problem, the present invention eliminates the conventional stabilizing circuit (3), and uses a deflection current correction means and a pulse voltage correction means to eliminate the influence of the high voltage caused by this and power supply voltage fluctuations on the deflection current flowing through the deflection yoke. An embodiment of the present invention will be described below with reference to FIG. 2, in which low loss and stabilized horizontal-plane current, high voltage, and DC voltage for signal systems are obtained by correction. Components having the same functions as those in FIG. 1 are given the same reference numerals and their explanations will be omitted. In addition, in the embodiment of the present invention, the conventional stabilizing circuit (3) is removed, so
An unregulated voltage (1) output from the power rectifier circuit (2) is applied to the horizontal deflection circuit via the primary winding L1 of the flyback transformer Tl. With this configuration, in a conventional horizontal deflection circuit, the deflection current changes according to the unstabilized voltage Vm.
However, in Fig. 2, this effect is avoided as follows. (7) is a generally known diode modulator circuit, and the voltage V across the capacitor C- is
By controlling the deflection yoke 1. ．． 6c is connected so that the flowing deflection current can be controlled, and here, as the voltage Vm becomes higher, the deflection current is controlled in the direction of being reduced.

T, is the secondary winding 1. is the collector voltage of the horizontal output transistor Q1 (a transformer connected in parallel between the lids of the horizontal output transistor Q1, which is a type of actuator used for pink blemish correction, and the voltage of the secondary winding Ls is The inductance is set larger than the inductance of the deflection yoke L1. Also, the capacitor C6 described in Lit is set smaller than the resonance capacitors Cy and C* of the single horizontal deflection path. (8) is a current control The circuit changes the inductance of the secondary winding Ls by controlling the current supplied to the primary winding L6 of the transformer T2 according to the unregulated voltage V.(9) is the unregulated voltage V A fluctuation detection circuit that controls the deflection current in a direction that keeps the deflection current constant according to the current.

It is composed of R□=R3, R4 and transistors Qz-Qs.

For example, if the unregulated voltage V is commercial lI! Consider a case where the temperature increases due to the influence of the source. Diode modulator circuit (7
), when the unregulated voltage Vm increases, the deflection current increases accordingly, but in the circuit of FIG. 2, when the unregulated voltage Vm increases, the resistance R1 in the fluctuation detection circuit (9) The voltage applied to the series circuit of node □ increases, and the resistance R
The voltage across □ increases, and the pace current 1. of transistor Q1 increases. This increase in the base current IB causes the collector voltage of the transistor Q□ to drop, and the collector-emitter of the transistor Q1 in the subsequent stage operates in the off direction, and the voltage across the capacitor C & - increases. As described above, as the voltage becomes higher than the principle of the diode modulator circuit ζ, the deflection current is controlled to be reduced, thereby canceling out the fluctuation of the unregulated voltage V in the increasing direction. Therefore, by appropriately selecting the gain of the fluctuation detection circuit (9), the deflection current can be kept constant even if the non-stabilized voltage Vm changes. Furthermore, when the unregulated voltage (1) increases, the current control circuit (1) reduces the current flowing through the primary winding (L) of the transformer T and increases the inductance of the secondary winding (L). Horizontal output transistor Q due to C
The maximum amplitude of the horizontal collector 1V pulse generated in the collector of s decreases, and the voltages generated on the high and low voltage sides of the flyback transformer Tl are controlled in the direction of decreasing, thereby increasing the unregulated voltage Vm. By appropriately designing the pupil flow control circuit (8) and the transformer T, even if the unregulated voltage Vm changes, the fluctuations in the output voltage caused by the fluctuations in the voltage Vm can be canceled out. The output voltage of the signal system can be kept constant.In addition, the diode modulator circuit (7), electric & control circuit (8), and fluctuation detection circuit (9)
In addition, the total loss of the transformer 7g is the same as that of the conventional stabilization circuit (3
) is sufficiently small compared to the loss caused by the design. Furthermore, since no component parts with large losses are required, the cost can be reduced compared to the conventional one using a stabilizing circuit.

As described above, according to the present invention, an unstabilized voltage is applied as the horizontal deflection circuit power supply voltage.

Since the horizontal deflection circuit is provided with a deflection current correction means and a pulse voltage correction means that control the deflection current and the amplitude of the horizontal collector pulse to be constant regardless of fluctuations in the non-stabilized voltage, the am+ circuit is not stabilized like the conventional one. It is possible to obtain stabilized high voltage and direct tltw & pressure for the signal system without using a conversion circuit, and it is also possible to perform stable horizontal deflection.
This makes it possible to reduce the power consumption and cost of television receivers.

[Brief explanation of drawings]

Figure 91 is a diagram of the conventional TV Gene receiver wLatt's IC source - schematic diagram %tM! The figure is an IIE source-schematic diagram of one embodiment of the present invention. (2)-1E 1lit II & @M, (7)-
r i 1' Soshii L/ -ta, (jlJ-・Current control circuit, (9)... Fluctuation detection circuit, ■, -Unregulated voltage s Tt ++・Fly bank transformer s t,,
++-direction Meek, Ql...Horizontal output transistor, T
I ・-) Lance agent Yoshihiro Morimoto

Claims (1)

[Claims] 1. Applying an unstabilized voltage as the horizontal deflection circuit power supply voltage, detecting fluctuations in the unstabilized voltage to the horizontal deflection circuit, and adjusting the deflection current and horizontal collector pulse regardless of this fluctuation. What is claimed is: 1. A television receiver comprising a deflection current correction means and a pulse voltage correction means for controlling the amplitudes of the signals to be constant. 1. The deflection current correction means is connected to the diode modifier circuit and 1li of the diode modifier according to the % voltage fluctuation.
Claims characterized by a fluctuation detection circuit for controlling the voltage of the llll terminal! The television receiver according to item 11. 1 The pulse voltage correction means includes a transformer whose secondary winding is connected in parallel to the output circuit of the horizontal output transistor via a capacitor, and a current that detects voltage fluctuations and controls the current supplied to the primary winding of the transformer. A television receiver according to claim 1, characterized in that the television receiver is configured with a control circuit;