JPH07210262A - Power circuit - Google Patents

Abstract

PURPOSE:To provide a poweer circuit which can supply the stabilized voltage to plural loads via a single constant voltage circuit. CONSTITUTION:A load A2 and the anode of a diode 3 are connected to a stabilized power circuit 1, and a capacitor 4 and a load B5 are connected in parallel to the cathode of the diode 3. The stabilized voltage supplied from the circuit 1 is applied to the load B5 and the capacitor 4 via the load A2 and the diode 3. If the power cunsumption of the load A2 suddenly increases and the current flowing to the load A2 suddenly increases, the output voltage of the circuit 1 temporarily drops. At the same time, the anode voltage of the diode 3 also drops. Thus the charge is outputted from the capacitor 4 and continuously supplied to the load B5 until the reverse current is prevented to the circuit 1 by the diode 3 and the output voltage of the circuit 1 is recovered. As a result, the voltage of the load B5 is stabilized.

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 particularly to a power supply circuit in which a plurality of loads are connected to a constant voltage circuit.

[0002]

2. Description of the Related Art Conventionally, a constant voltage circuit to which a plurality of power consuming loads are connected has a configuration as shown in FIG.

Stabilized power supply circuit 2 as a DC constant voltage circuit
0 receives electric power from a power source (not shown) and outputs a stable voltage. The output stabilized voltage is the load E21.
And the load F22. In this way, the load E
21 and the load F22 were supplied with a constant voltage.

[0004]

In the conventional stabilized power supply circuit 20 as described above, if the currents flowing into the plurality of loads E21 and F22 are constant or slightly changed, the output voltage hardly changes. . However, even in one of the plurality of loads E21 and F22, when the power consumption rapidly changes and the current flowing into the load changes significantly, the output voltage fluctuates due to the response delay of the stabilized power supply circuit 20, and There was a problem that it affected the load of.

As a method for solving this problem, as shown in FIG. 4, a stabilized power supply circuit 23 is connected to a load G25,
A method of connecting the stabilized power supply circuit 24 to the load H26 has also been proposed. However, in this method, since the stabilized power supply circuit is used by the number of loads, there are problems such as an increase in cost and an increase in size of the power supply circuit.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to supply a stable voltage to a plurality of loads by a single constant voltage circuit. It is to provide a power supply circuit.

[0007]

In order to achieve this object, according to claim 1 of the present invention, a constant voltage circuit which is supplied with power from a power source and outputs a stabilized voltage, and an output side of the constant voltage circuit. A rectifying element connected in series between the constant voltage circuit and the load, the rectifying element flowing a current only in one direction, and an output side of the rectifying element. In, a storage element connected in parallel with the load and storing electric charge is provided.

According to a second aspect of the present invention, the rectifying element is a diode.

According to a third aspect of the present invention, the storage element is a capacitor.

[0010]

In the power supply circuit of the present invention having the above structure, the rectifying element connected in series between the output of the constant voltage circuit and the load allows the current to flow in only one direction, and the output side of the rectifying element. In, when the storage element connected in parallel with the load accumulates electric charge and the output voltage of the constant voltage circuit decreases,
The charge is output from the power storage element and is supplied to the load. At this time, backflow of charges is prevented by the rectifying element.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the power supply circuit of the present invention will be described below with reference to FIG.

The stabilized power supply circuit 1 as a constant voltage circuit is
Electric power is input from a power source (not shown) and a stable voltage is output. Then, on the output side of the stabilized power supply circuit 1, a load A2 whose power consumption varies greatly and a diode 3 as a rectifying element are connected in parallel. The anode of the diode 3 is connected to the output side of the stabilized power supply circuit 1. Then, to the cathode of the diode 3, a capacitor 4 as a storage element and a load B5 in which the power consumption hardly fluctuates are connected in parallel. In addition, 0V of power supply
Is the 0V terminal of the stabilized power supply circuit 1, the load 1, and the load B5.
Connected to the 0V terminal of the capacitor 4 and the 0V terminal of the capacitor 4. Here, as the diode 3, a PN junction diode, a Schottky barrier diode, a PIN diode or the like is used. When there are multiple loads with almost no fluctuation in power consumption, the diode cathode
Individual loads and capacitors are connected in parallel.

Next, the operation will be described. The power from the power supply is input to the stabilized power supply circuit 1, and the stabilized power supply circuit 1 outputs a stabilized voltage. The stabilized voltage is given to the load B5 and the capacitor 4 via the load A2 and the diode 3. As a result, the load A2 and the load B5 consume power to perform their respective functions, and the capacitor 4 accumulates charges.

Therefore, when there is almost no change in the power consumption of the load A2 and the load B5 and the current value flowing into the load A2 and the load B5 is constant or minute, the output voltage of the stabilized power supply circuit 1 is maintained at a constant voltage. , Load A2, load B5
The voltage applied to is also kept constant. And the load A2
When the current consumption flowing into the load A2 suddenly increases due to the sudden increase in the power consumption of, the response voltage of the stabilized power supply circuit 1 is finite, and thus the output voltage of the stabilized power supply circuit 1 temporarily decreases. . At that time, the voltage of the anode of the diode 3 also drops at the same time.

Here, the capacitor 4 connected in parallel with the load B5 connected to the cathode of the diode 3 is
Since the output of the stabilized power supply circuit 1 is charged to the voltage before the output drops, the electric charge is output from the capacitor 4 to the diode 3 side. Then, the charge output from the capacitor 4 is supplied to the load B5 until the diode 3 prevents the backflow to the stabilized power supply circuit 1 side and the output voltage of the stabilized power supply circuit 1 is recovered. The voltage of B5 is kept constant. After that, the output voltage of the stabilized power supply circuit 1 is restored, and the voltage of the load B5 is always constant. The capacity of the capacitor 4 is sufficiently large with respect to the amount of electric charge output from the capacitor 4 during the time required for the stabilized power supply circuit 1 to recover.

As described above in detail, since the diode 3 is connected in series between the stabilized power supply circuit 1 and the load B5 and the capacitor 4 is connected in parallel with the load B5, the stabilized power supply circuit is provided. Even if the output voltage of No. 1 temporarily drops, the voltage of the load B5 can be kept constant by the capacitor 4. Therefore, unlike the conventional case, it does not need the stabilized power supply circuit for the number of loads, and the cost is reduced.
The circuit can be miniaturized. In particular, when the load B5 has a voltage value detection function, other functions may be reset even if the voltage drops temporarily. Therefore, as in this embodiment, the voltage of the load B5 is reduced. Is constant, it works well without the other features being reset.

Further, since the diode is used as the rectifying element, the cost is low and the circuit can be downsized. Further, since the capacitor is used as the power storage element, the life of the power storage element is semi-permanent and replacement is unnecessary.

In the embodiment shown in FIG. 1, it has been explained that the power consumption of the load A2 fluctuates greatly and the power consumption of the load B5 hardly fluctuates, but in the embodiment shown in FIG. An explanation will be given of a case where both the load D8 and the power consumption vary greatly. In this case, the stabilized power supply circuit 6
The anodes of the diodes 9 and 10 are connected to the output side of the. Capacitors 11 and 12 and loads C7 and D8 are connected in parallel to the cathodes of the diodes 9 and 10.
Further, 0V of the power supply is connected to the 0V terminal of the stabilized power supply circuit 6, the 0V terminals of the loads C7 and D8, and the 0V terminals of the capacitors 11 and 12. In this way, the loads C7, D
It is possible to eliminate the influence of fluctuations in power consumption of each other.

Further, in the case where the power consumption of a plurality of loads fluctuates drastically and the power consumption of a load hardly fluctuates, the output side of the stabilized power supply circuit is
A diode and a capacitor are provided for each load as shown in FIG. Furthermore, the fluctuations in the power consumption of multiple loads are severe,
In addition, a description will be given of a case where there is almost no change in the power consumption of a plurality of loads. In this case, for a load whose power consumption varies greatly, a diode and a capacitor are provided for each load on the output side of the stabilized power supply circuit as shown in FIG. For a load with almost no fluctuation in power consumption, the anode of the diode is connected to the output side of the stabilized power supply circuit, and one capacitor and each load are connected in parallel to the cathode of the diode.

The present invention is not limited to the above embodiment, and the capacitor may be replaced with a battery. Further, the diode can be replaced with a transistor, a rectifying tube, a selenium rectifier, or the like.

[0021]

As is apparent from the above description, according to the power supply circuit of the present invention, the rectifying element is connected in series between the output of the constant voltage circuit and the load, and the output side of the rectifying element is connected. In, the storage element is connected in parallel with the load, so that when the output voltage of the constant voltage circuit decreases, the charge is supplied from the storage element to the load. At this time, the reverse flow of the output charge is prevented by the rectifying element, and the charge is satisfactorily supplied to the load. Therefore, a single constant voltage circuit can always supply a stable voltage to the load.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an embodiment embodying a power supply circuit of the present invention.

FIG. 2 is a diagram showing a configuration of a modified example in which the power supply circuit of the present invention is embodied.

FIG. 3 is a diagram showing a configuration of a conventional power supply circuit.

FIG. 4 is a diagram showing a configuration of a conventional power supply circuit.

[Explanation of symbols]

 1 Stabilized power supply circuit 2 Load A 3 Diode 4 Capacitor 5 Load B

Claims (3)

[Claims] 1. A power supply circuit comprising a constant voltage circuit which is supplied with power from a power supply and outputs a stabilized voltage, and a plurality of loads which are connected to the output side of the constant voltage circuit and consume power. A rectifying element that is connected in series between the constant voltage circuit and the load and that allows current to flow in only one direction, and an electric storage element that is connected in parallel to the load and that stores electric charge on the output side of the rectifying element. A power supply circuit characterized by the above. 2. The power supply circuit according to claim 1, wherein the rectifying element is a diode. 3. The power supply circuit according to claim 1, wherein the power storage element is a capacitor.