JPH06245550A - Power supply circuit - Google Patents

Abstract

PURPOSE:To provide a small, lightweight power supply circuit having a simple configuration. CONSTITUTION:A capacitor Co is connected in parallel to a pulsating current generating circuit, and diodes D1u and D2u are connected in parallel to a terminal at the opposite side of the pulsating current generating circuit of the capacitor Co. Zener diodes ZD1u and ZD2u are connected in parallel to the diodes D1u and D2u, and capacitors C1u and C2u are connected in parallel to the Zener diode ZD1u and ZD2u. A connecting point between the Zener diodes ZD1u and ZD2u and a connecting point between the capacitors C1u and C2u are connected commonly to a reference line Lsu and also to the pulsating current generating circuit. Potential of a terminal at the cathode side of the Zener diode ZD1u of the capacitor C1u becomes a DC output Vpp and the potential of a terminal at the anode side becomes a DC output Vnn.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply circuit, and more specifically, to a direct current power supply, by combining transistors in two stages and turning on / off each transistor,
The present invention relates to a power supply circuit necessary for driving each transistor of a transistor bridge circuit that takes out an output from a connection point of a pair of transistors in each stage at high speed.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing an electrical configuration of a DC / AC converter (hereinafter abbreviated as a converter) 1 according to the prior art. Two transformers 3 and 4 are connected in parallel with the AC power supply 2, and a diode bridge circuit 5 is further connected. A smoothing capacitor 6 is connected between a pair of output terminals of the diode bridge circuit 5. A diode 7 is connected in series to the secondary side of the transformer 3, and a smoothing capacitor 8 is connected in parallel. A resistor 9 is connected in parallel to the cathode of the diode 7, and a series circuit of a transistor 10 and a resistor 11 is connected in parallel with the capacitor 8. The node of the diode 12 is connected to the connection point between the transistor 10 and the resistor 11, and its cathode is connected to the base of the transistor 13 and further to the emitter of the transistor 14. . Transistor 1
The base of 4 is connected to the anode of the diode 12, and its collector is connected to the secondary side of the transformer 3. The collector of the transistor 13 is connected to one terminal of the capacitor 6, and its emitter is connected to the collector of the transistor 14.

A circuit having the same configuration as the circuit connected to the secondary side of the transformer 3 is connected to the secondary side of the transformer 4. The description of the configuration of the same circuit connected to the secondary side of the transformer 4 is omitted. When the components corresponding to the above-described components of the circuit connected to the transformer 3 are shown, the reference numerals 7 to 13 are indicated by adding a subscript a. A control signal for turning on / off the transistors 10 and 10a is supplied to each base of the transistors 10 and 10a.
Each is supplied. The emitter of the transformer 13 is connected to the output terminal 15 of the collector of the transistor 13a and serves as an AC output from the converter 1 of the conventional example. That is, in this conventional example, the DC voltage from the capacitor 6 is
By the switching operation of the transistors 13 and 13a, a pulsating current voltage is output from the output terminal 15.

[0004]

In the converter 1 of the above-mentioned conventional example, the pulsating voltage is generated by the transistors 13 and 13a on the basis of the DC voltage from the capacitor 6, so that the transistors 10 and 10a have the pulsating voltage. The driving power supplied requires the AC power supply 2 and the transformers 3 and 4. Therefore, there is a problem that the structure of the converter 1 becomes large and the weight increases. Further, since the AC power supply 2 is required, the type of power supply of the converter 1 is limited, and there is a problem that usability is low.

An object of the present invention is to solve the above-mentioned technical problems and to provide a power supply circuit which can achieve a reduction in size and weight and a simplification of the configuration.

[0006]

According to the present invention, there is provided a direct current generating means for generating a direct current, and one output terminal of the direct current generating means, which is connected in series with the direct current generating means and in parallel with each other.
A plurality of smoothing means for smoothing the input direct current, a plurality of constant voltage generating means connected in parallel to each smoothing means and respectively generating a predetermined constant voltage, and any one of the plurality of smoothing means. And a plurality of rectifying means connected in series to each set of one of the plurality of constant voltage generating means, each rectifying means being reversely connected to each other. Is.

[0007]

According to the present invention, the direct current generating means generates a direct current. A plurality of smoothing means are connected to one output end of the DC generating means in series with the DC generating means and in parallel with each other. A plurality of constant voltage generating means are connected in parallel to the respective smoothing means and generate a predetermined constant voltage.
A plurality of rectifying means is connected in series to each set including one of the plurality of smoothing means and one of the plurality of constant voltage generating means. The plurality of rectifying means,
Reverse connected to each other.

Therefore, a structure for generating a DC voltage can be used as the power supply. This eliminates the need for a circuit such as a transformer that generates a DC voltage from an AC voltage, which is required when an AC power supply is used. That is, in the present invention, the size and weight of the structure can be reduced, and the structure can be further simplified.

[0009]

1 is a block diagram showing the basic construction of the present invention. The circuit of the present invention is the power supply circuit 21, and based on the pulsating flow signal from the pulsating flow generation circuit 22, the output line L1.
A positive DC output Vpp and a negative DC output Vnn are obtained from u and L2u, respectively. A capacitor C0 is connected in parallel with the pulsating current generating circuit 22, and diodes D1u and D2u are connected in parallel with the terminal of the capacitor C0 opposite to the pulsating current generating circuit 22. Dio
Zener diode ZD1 in parallel with D1u and D2u
u and ZD2u are connected. Zener diode ZD1
In parallel with u and ZD2u, capacitors C1u and C2u made of, for example, electrolytic capacitors are connected. The connection point between the Zener diodes ZD1u and ZD2u and the connection point between the capacitors C1u and C2u are commonly connected to the reference line Lsu, and the pulsating current generation circuit 22 is also provided.
Connected to. The potential of the terminal on the cathode side of the Zener diode ZD1u of the capacitor C1u is the DC output V
pp. Zener diode Z of capacitor C2u
The potential of the terminal on the anode side of D1u is equal to the DC output Vn.
n.

The operation of the power supply circuit 21 is as follows. When the pulsating flow is supplied from the pulsating flow generation circuit 22 to the capacitor C0, an alternating current flows through the capacitor C0. This alternating current is rectified by the diodes D1u and D2u and smoothed by the capacitors C1u and C2u. As a result, a DC output Vpp having a positive potential with respect to the reference potential on the reference line Lsu is obtained at the output line L1u, and a DC output having a negative potential with respect to the reference potential on the reference line Lsu is obtained at the output line L2u. Vnn is obtained.

Here, as an example, when the level of the DC outputs Vpp and Vnn exceeds a predetermined specified value due to a cause such as the level of the pulsating flow from the pulsating flow generation circuit 22 becoming excessive, the capacitor C0 The current flows through the Zener diodes ZD1u and ZD2u. This limits the charging current to the capacitors C1u and C2u. That is, it is possible to prevent the levels of the DC outputs Vpp and Vnn from exceeding a predetermined specified value.

FIG. 2 shows a power supply circuit 31 according to an embodiment of the present invention.
3 is a block diagram showing an example of the electrical configuration of FIG. A DC power supply 32 is used in the power supply circuit 31 of this embodiment, and a control circuit 33 is connected in parallel with the DC power supply 32. Control circuit 3
3 includes a pair of open-collector-connected drive transistors 34 and 35, respectively, and a switch control signal is output from the drive transistors 34 and 35 driven by a control signal from an external controller (not shown).

Power supply line 3 connected to DC power supply 32
Transistor drive circuits 38 and 39 are connected in parallel between 6 and 37. The transistor drive circuits 38 and 39 are
From the output lines L1u, L2u; L1d, L2d, a positive-sign DC output Vpp and a negative-sign DC output Vnn are respectively output. The transistor drive circuit 3
The capacitor C0 is arranged between 8 and 39. The structure of the transistor drive circuit 38 is as follows. Diodes D1u and D2u are connected in parallel to the terminal of the capacitor C0 on the transistor drive circuit 38 side. Dio
Zener diode ZD1 in parallel with D1u and D2u
u and ZD2u are connected. Zener diode ZD1
In parallel with u and ZD2u, capacitors C1u and C2u made of, for example, electrolytic capacitors are connected.

The cathode of the Zener diode ZD1u is connected to the power supply line 36 via the resistor R1u. The connection point between the Zener diodes ZD1u and ZD2u and the connection point between the capacitors C1u and C2u are commonly connected to the reference line Lsu. Reference line Lsu
Is connected to the output line Lout. Capacitor C1
The potential of the terminal on the cathode side of the Zener diode ZD1u of u is output to the output line L1u and becomes the DC output Vpp. Zener diode of capacitor C2u
The potential of the terminal on the anode side of the gate ZD1u is output to the output line L2u and becomes the DC output Vnn.

A resistor R is connected in parallel to the output line L1u.
2u is connected, and a series circuit of a transistor Q1u and a resistor R3u is connected in parallel with the capacitor C1u. The node of the diode 40 is connected to the connection point between the transistor Q1u and the resistor R3u, and its cathode is connected to the gate of the transistor Qu and further to the emitter of the transistor Q2u. . The base of the transistor Q2u is connected to the node of the diode 40, and its collector is connected to the output line L2u. The source of the transistor Qu is connected to the power supply line 36,
The drain is connected to the output line Lout and also to the drain of the transistor Qd included in the transistor drive circuit 39.

On the other hand, the structure of the transistor drive circuit 39 is as follows. Diodes D1d and D2d are connected in parallel to the terminal of the capacitor C0 on the transistor drive circuit 39 side. Zener diodes ZD1d and ZD2d are connected in parallel with the diodes D1d and D2d. In parallel with the Zener diodes ZD1d and ZD2d, capacitors C1d and C2, which are electrolytic capacitors, for example, are used.
d is connected.

The cathode of the Zener diode ZD1d is connected to the output line Lout via the resistor R1d. The connection point between the Zener diodes ZD1d and ZD2d and the connection point between the capacitors C1d and C2d are commonly connected to the reference line Lsd. The potential of the terminal on the cathode side of the Zener diode ZD1d of the capacitor C1d is output to the output line L1d and becomes the DC output Vpp. The potential of the anode side terminal of the Zener diode ZD1d of the capacitor C2d is output to the output line L2d and becomes the DC output Vnn.
The output line L2d is connected to the output line Lout.

A resistor R is connected in parallel to the output line L1d.
2d is connected, and a series circuit of a transistor Q1d and a resistor R3d is connected in parallel with the capacitor C1d. The node of the diode 41 is connected to the connection point between the transistor Q1d and the resistor R3d, the cathode of which is connected to the gate of the transistor Qd and further to the emitter of the transistor Q2d. It Transistor Q2
The base of d is connected to the anode of the diode 41, and its collector is connected to the output line L2d. The source of the transistor Qd is connected to the power supply line 37, and the drain thereof is connected to the output line Lout.

A control signal for turning on / off the transistors Q1u, Q1d is applied to each of the bases of the transistors Q1u, Q1d.
Supplied from each.

The operation of the power supply circuit 31 is as follows. The control circuit 33 controls the transistor Q1
When u and Q1d are alternately turned on / off, an alternating current flows through the capacitor C0. This alternating current is rectified by the diodes D1u and D2u in the drive circuit 38 and smoothed by the capacitors C1u and C2u. Further, in the drive circuit 39, it is rectified by the diodes D1d and D2d and smoothed by the capacitors C1d and C2d. As a result, a DC output Vpp having a positive potential with respect to the reference potential on the reference line Lsu is obtained on the output lines L1u and L1d. Also, the output line L
DC outputs Vnn having a negative potential with respect to the reference potential on the reference line Lsu are obtained at 2u and L2d.

Here, as an example, when the level of the DC outputs Vpp and Vnn exceeds a predetermined specified value due to an excessive level of alternating current from the capacitor C0, the current from the capacitor C0 becomes -Diodes ZD1u and ZD2u; flow to ZD1d and ZD2d. As a result, the capacitors C1u, C2u; C1d,
The charging current to C2d is limited. That is, it is possible to prevent the levels of the DC outputs Vpp and Vnn from exceeding a predetermined specified value.

In this way, the drive circuits 38, 39
On the other hand, it is possible to realize a power supply circuit that does not use a transformer as in the related art. Therefore, the power supply circuit 3
The structure of No. 1 is made smaller and lighter. Also, since no AC power supply is required, the type of power supply of the power supply circuit is not limited,
Usability is significantly improved.

[0023]

As described above, according to the present invention, the direct current generating means generates a direct current. A plurality of smoothing means are connected to one output end of the DC generating means in series with the DC generating means and in parallel with each other. A plurality of constant voltage generating means are connected in parallel to the respective smoothing means and generate a predetermined constant voltage. A plurality of rectifying means is connected in series to each set including one of the plurality of smoothing means and one of the plurality of constant voltage generating means. The plurality of rectifying means are reversely connected to each other.

Therefore, a structure for generating a DC voltage can be used as the power supply. This eliminates the need for a circuit such as a transformer that generates a DC voltage from an AC voltage, which is required when an AC power supply is used. That is, in the present invention, the size and weight of the structure can be reduced, and the structure can be further simplified.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a configuration of the present invention.

FIG. 2 is a circuit diagram showing an embodiment of the present invention.

FIG. 3 is a prior art circuit diagram.

[Explanation of symbols]

21 power supply circuit 31 DC power supply L1u, L2u; L1d, L2d output line Vpp, Vnn DC output C0; C1u, C2u; C1d, C2d capacitor D1u, D2u; D1d, D2d diode ZD1u, ZD2u; ZD1d; -Do

Claims (1)

[Claims] 1. A direct current generating means for generating a direct current, and a plurality of direct current generating means connected to one output end of the direct current generating means in series and in parallel with each other to smooth an input direct current. Smoothing means, a plurality of constant voltage generating means connected in parallel to each smoothing means and respectively generating a predetermined constant voltage, any one of the plurality of smoothing means, and any one of the plurality of constant voltage generating means A power supply circuit comprising a plurality of rectifying means connected in series to each set of one rectifying means, each rectifying means being reversely connected to each other.