JP2001218371A - Power circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size or omit a power transformer. SOLUTION: The negative electrodes of batteries 3A and 3B are grounded. The battery 3A is charged vig a diode 5A and a switch circuit 4A by pulse power source, and is discharge via a switch circuit 4A and a diode 6A. The battery 3B is charged via a diode 5B and a switch 4B by the pulse power source, and is discharged via a switch circuit 4B and a diode 6B. A controller 9 detects the quantity of charge and the quantity of discharge of the batteries 3A and 3B and controls the switch circuits 4A and 4B, so that the charging condition and discharging condition of the batteries 3A and 3B alternate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a power supply circuit used for, for example, an audio Hi-Fi amplifier.

[0002]

2. Description of the Related Art A power supply circuit for an audio amplifier is basically configured to supply a commercial power supply to a rectifier via a power supply transformer and supply a rectified output to a power supply terminal of the amplifier via a smoothing capacitor. ing. The power transformer is required to have a characteristic in which the voltage and current of each winding satisfy required values in circuit design, have a small voltage fluctuation rate, and have a small temperature rise.

[0003]

In the Hi-Fi amplifier, since the above-mentioned requirements are severe, the power transformer becomes heavy, large, and expensive. In recent years, when music is downloaded and played on a personal computer, such as electronic music distribution, the need for a large power transformer is especially important for portable devices such as notebook computers. Inconvenience occurs.

Accordingly, it is an object of the present invention to provide a power supply circuit capable of reducing or eliminating a power supply transformer.

[0005]

In order to solve the above-mentioned problems, the invention according to claim 1 comprises first and second rechargeable batteries each having one electrode connected to a reference potential point; First switching means for switching between a charging state in which the other electrode of the first battery is connected to the input power source and a discharging state in which the other electrode of the first battery is connected to the output terminal; Second switch means for switching between a charged state in which the other electrode is connected to the input power source and a discharged state in which the other electrode of the second battery is connected to the output terminal; and the charge amounts of the first and second batteries And a control unit that detects the amount of discharge and controls the first and second switch means so that the charge state and the discharge state of the first and second batteries alternately occur. A power supply circuit.

In the present invention, two batteries are used, and when one is in a charged state, the other is controlled to be in a discharged state. Since the battery is used as a very high-capacity capacitor, the power transformer can be reduced in size, weight, or omitted, and can supply a large amount of power at a low impedance required by a load, for example, an audio amplifier. be able to.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, 1 is a commercial power supply (for example, 100 V, 60 Hz), and 2 is an A / D converter. The A / D converter 2 forms a pulse power supply that outputs a positive pulse voltage. Note that a pulse power supply such as a switching power supply may be used instead of the A / D converter 2. 3A and 3B are rechargeable batteries such as lithium ion, lithium hydrogen, and polymer batteries, respectively. The batteries 3A and 3B have the same characteristics such as capacity. Battery 3A, 3
Preferably, the series impedance of each of B is small.

[0008] One electrode (negative side) of the batteries 3A and 3B is grounded. The other electrode (positive side) of battery 3A is connected to the cathode of diode 5A via terminals a and b of switch circuit 4A. Diode 5
The anode of A is connected to the output terminal of A / D converter 2. Similarly to the battery 3A, the other electrode (positive side) of the battery 3B is connected to the output terminals of the A / D converter 2 via the terminals a and b of the switch circuit 4B and the diode 5B in the reverse direction.

The electrode (positive side) of the battery 3A is connected to the terminals a and c of the switch circuit 4A and the output terminal 7 via the forward diode 6A. Similarly, the electrode (positive side) of the battery 3B is connected to the terminal a of the switch circuit 4B.
And c, and to the output terminal 7 via a forward diode 6B. A capacitor 8 is inserted between the output terminal 7 and the ground. The output terminal 7 is connected to a load such as an amplifier. The capacitor 8 is inserted to cut off pulse noise generated by a potential difference between the batteries 3A and 3B.

The switching operation of the switch circuits 4A and 4B is controlled by the control unit 9. The control unit 9 detects the respective terminal voltages and charging or discharging currents of the batteries 3A and 3B, and compares the reference current and voltage with the detected voltage and current, respectively, to switch the switch circuits 4A and 4B. Generate a control signal to switch. When no load is connected to the output terminal 7, both of the switch circuits 4A and 4B are connected to the terminals a and b.
Are connected, and the batteries 4A and 4B are charged.

When a load is connected to the output terminal 7, one of the switch circuits 4A and 4B is connected to the terminals a and b (charged state), and the other is connected to the terminals a and c. (Discharge state), and the state is switched between the charge state and the discharge state. Thereby, the output can be kept constant and the batteries 3A, 3B can be kept charged. In the discharged state, the batteries 3A and 3B function as extremely high-capacity capacitors, so that large-capacity power can be supplied at low impedance required by the amplifier.

FIG. 2 shows another embodiment of the present invention.
In another embodiment, power is supplied to an amplifier 21 (for example, an OCL push-pull amplifier) that operates on two power supplies. The amplifier 21 amplifies the audio signal from the input terminal 22 and outputs it to the output terminal 23. For example, a speaker is connected to the output terminal 23. For example, the amplifier 21 is used in an audio signal system in a portable personal computer.

The structure for forming the power supply on the positive side of the amplifier 21 is the same as that of the embodiment (FIG. 1), and the corresponding portions are denoted by the same reference characters and description thereof is omitted. The negative power supply of the amplifier 21 is generated by the batteries 13A and 13B. The positive electrodes of the batteries 13A and 13B are grounded. A negative electrode of the battery 13A is connected to terminals a and b of the switch circuit 14A and a negative output terminal of the A / D converter 2 via a forward diode 15A. Similarly, a negative electrode of the battery 13B is connected to terminals a and b of the switch circuit 14B and a negative output terminal of the A / D converter 2 via a forward diode 15B.

The negative electrode of the battery 13A is connected to the negative power supply terminal 17 of the amplifier 21 via a diode 16A in a direction opposite to the terminals a and c of the switch circuit 14A. Similarly, the negative electrode of the battery 13B is connected to the diode 16 in the opposite direction to the terminals a and c of the switch circuit 14B.
It is connected to the negative power supply terminal 17 of the amplifier 21 via B. A capacitor 18 is inserted between the negative power supply terminal 17 and the ground in order to cut off pulse noise generated by the potential difference between the batteries 13A and 13B.

The switching operation of the switch circuits 14A and 14B is controlled by the control unit 19. Control unit 19
Is a control signal for switching the switch circuits 14A and 14B by detecting respective terminal voltages and charge or discharge currents of the batteries 13A and 13B, and comparing the reference current and voltage with the detected voltage and current, respectively. Occurs.

Similarly to the positive power supply, the switch circuit 14A
One of terminals 14B and 14B is in a state where terminals a and b are connected (charged state), the other is in a state where terminals a and c are connected (discharged state), and the state is switched between a charged state and a discharged state. Thus, the output of the negative power supply can be kept constant, and the batteries 13A and 13B can be kept charged.

In another embodiment, the batteries 3A, 3B, 13B in the discharged state are similar to the above-described embodiment.
Since A and 13B function as extremely high-capacity capacitors, it is possible to supply large-capacity power with low impedance required by the amplifier 21.

[0018]

According to the present invention, by using a battery as an extremely large-capacity capacitor, a heavy and large power transformer used in a conventional power circuit can be reduced in size, weight, or omitted. be able to. In addition, the conventional power transformer had a unique shape and was inflexible.However, in the present invention, a battery having a limited shape, such as a polymer battery, can be used, so that a product It is possible to increase the degree of freedom of the form.

[Brief description of the drawings]

FIG. 1 is a connection diagram of an embodiment of the present invention.

FIG. 2 is a connection diagram of another embodiment of the present invention.

[Explanation of symbols]

1 ... commercial power supply, 3A, 3B, 13A, 13B ...
Rechargeable battery, 4A, 4B, 14A, 14B
..Switch circuits, 9, 19... Control units

Claims (2)

[Claims] 1. A chargeable first and second battery each having one electrode connected to a reference potential point; a charging state connecting the other electrode of the first battery to an input power source; A first battery for switching a discharging state for connecting the other electrode of the first battery to an output terminal;
Switch means for switching between a charging state in which the other electrode of the second battery is connected to an input power source and a discharging state in which the other electrode of the second battery is connected to an output terminal.
Switch means for detecting the amount of charge and the amount of discharge of the first and second batteries, and the first and second switches so that the state of charge and the state of discharge of the first and second batteries alternately occur. A power supply circuit, comprising: a control unit that controls the second switch means. 2. The battery according to claim 1, further comprising third and fourth rechargeable batteries each having one electrode connected to a reference potential point, and the other electrode of the third battery serving as an input power supply. A third state for switching between a charged state to be connected and a discharged state to connect the other electrode of the third battery to an output terminal.
Switch means for switching between a charging state in which the other electrode of the fourth battery is connected to an input power source and a discharging state in which the other electrode of the fourth battery is connected to an output terminal.
And a switch means for detecting the amount of charge and the amount of discharge of the third and fourth batteries, and changing the state of charge and the state of discharge of the third and fourth batteries alternately. A control unit for controlling fourth switch means, wherein the first and second batteries form one of the positive and negative power supplies, and the third and fourth batteries form the other of the positive and negative power supplies. A power supply circuit characterized by: