JP3095093U - Power supply auxiliary circuit - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To assist the power supply after a voltage drop of a secondary battery for a certain period of time to prevent the device main body from becoming inoperable before necessary treatment, and to improve reliability. Power supply to a highly reliable device body. SOLUTION: A charging circuit 21 including a plurality of electric double-layer capacitors 22 charged between a secondary battery for supplying electric power to an apparatus main body and a power supply voltage from the secondary battery and charging the apparatus main body; A changeover switch 11 for switching a path for supplying power to the apparatus main body to either the wiring 12 on the secondary battery side or the wiring 13 on the charging circuit 21 side, and a power supply voltage supplied from the secondary battery to the apparatus main body side are measured. A power supply auxiliary circuit 10 comprising: a detection circuit 15 for switching the power supply path to the apparatus main body by the changeover switch 11 from the secondary battery side to the charging circuit side when detecting that the voltage has become lower than a preset voltage. Is arranged.

Description

[Detailed description of the device]

[0001]

[Technical field to which the device belongs]

  The present invention relates to a power auxiliary circuit that assists a secondary battery that repeats charging and discharging, and Is an emergency when the voltage of the secondary battery drops to such an extent that the operation of the main body of the device cannot be maintained. In addition, the present invention relates to a power auxiliary circuit capable of supplying electric power instead of the secondary battery.

[0002]

[Prior art]

  Portable electronic devices related to mobile devices have been developing rapidly in recent years. In the power circuit of the battery, use a battery such as a lead battery, CADNICA battery, nickel-hydrogen battery, etc. It incorporates a secondary battery that can be repeatedly discharged.

[0003]   With this kind of electronic device, always set to 2 to avoid accidentally becoming inoperable. Monitor the power supply voltage of the secondary battery and take necessary measures when the power supply voltage drops. Need to execute The power supply voltage of this secondary battery is generally the electronic device The voltage measurement circuit connected to the body constantly measures. The power source of the secondary battery Various voltage detection methods have been put into practical use, for example, the discharge voltage of a battery is After the voltage has dropped to the specified voltage value, the remaining power is calculated based on the charging current and discharging current. It is being put out.

[0004]

[Problems to be solved by the device]

  However, in such a conventional power supply circuit, the power supply voltage of the secondary battery is Since it only detects it, necessary measures are not taken in time and the device body does not operate carelessly. However, there was a problem that data might be lost. .

[0005]   Therefore, the present invention has been made in view of the above-mentioned circumstances, and the voltage of the secondary battery is low. By assisting the power supply for a certain period of time after the Power supply to the highly reliable device body is made possible by making it possible to avoid becoming impossible to operate. The purpose is to realize salary.

[0006]

[Means for Solving the Problems]

  An idea of a power supply auxiliary circuit that solves the above problems is to provide a secondary power source for supplying power to the main body of the apparatus. A power supply auxiliary circuit arranged between the pond and the main body of the device, which is a power supply from a secondary battery A charging circuit comprising one or a plurality of capacitors that are charged by applying a voltage, and a device Switch the power supply path to the main body to either the secondary battery or the charging circuit Changeover switch and the power supply voltage that the secondary battery supplies to the main unit of the device are measured and set in advance. A device that uses a changeover switch when it detects that the voltage has dropped below the specified voltage. A detection circuit that switches the power supply path to the main unit from the secondary battery side to the charging circuit side is installed. It is characterized by the fact that it has been broken.

[0007]   In this invention, the capacitor of the charging circuit is initially charged by the power of the secondary battery. Then, when the secondary battery drops below the set voltage, the power supply The road is switched to the charging circuit side. Therefore, due to the voltage drop of the secondary battery, the device The main body will not immediately become inoperable, and the charging circuit will be replaced by a secondary battery. Power can be urgently supplied to the device body.

[0008]   Here, the power supply auxiliary circuit of the present invention uses an electric double layer capacitor as a charging circuit. It is preferable that a secondary battery is provided between the changeover switch and the main body of the apparatus. A relay circuit consisting of one or more capacitors that are charged by applying the power supply voltage of When the discharge is confirmed by arranging or monitoring the discharge of the charging circuit, the detection signal is detected. It is preferable to provide an output circuit for outputting the signal.

[0009]

[Embodiment of device]

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Fig. 1 is the present invention It is a figure which shows one Embodiment of the power supply auxiliary circuit which concerns on.

[0010]   In FIG. 1, a power supply auxiliary circuit 10 is a mobile device that can be operated while being carried. Built into the power circuit of electronic equipment together with a secondary battery that supplies power to the device It is rare. This power supply auxiliary circuit 10 connects the power supply input terminal 10a to the secondary battery side. The power output terminal 10b is connected to the main body of the device, and the power of the secondary battery is Stable supply of source voltage to the main unit.

[0011]   Here, the secondary battery is, for example, a lead battery, a CADNICA battery, or a nickel-hydrogen battery. How to set it in the charger or connect it to a solar panel etc. It can be charged. Power supply circuit is DC output (electric power) from the secondary battery However, if the output voltage is used as it is, the supply voltage will change over time. In order to ensure stable operation of the device body, it is generally D Designed to supply a stable power supply voltage via a C-DC converter Has been done.

[0012]   The power supply auxiliary circuit 10 includes a power supply input terminal 10a and a power supply output terminal 10b. A changeover switch 11 is interposed between the changeover switch 11 and the changeover contact 11a of the changeover switch 11. 11b are respectively connected to the wirings 12 and 13 which are electrically connected to the power input terminal 10a, The common contact 11c of the spare switch 11 is connected to the wiring 14 that is electrically connected to the power output terminal 10b. Has been continued. As a result, the changeover switch 11 has the power input terminal 10a and the power output. The conduction path with the terminal 10b can be switched.

[0013]   The changeover switch 11 is a power source for the secondary battery supplied from the power source input terminal 10a. The voltage drop detection circuit 15 for measuring (monitoring) the voltage is connected and switching-controlled. This Is a device in which the power supply voltage at the power supply input terminal 10a is preset. The voltage has dropped below the specified voltage required for normal operation of the main unit (DC-DC converter). When a switch is detected, a detection signal (drive signal) is sent to the common switch By changing the short circuit with the point 11c from the switching contact 11a to the switching contact 11b, the wiring 14 and The conduction path of is switched from the wiring 12 to the wiring 13.

[0014]   A charging circuit 21 is connected to the wiring 13, and a relay circuit 31 is connected to the wiring 14. Has been continued. The charging circuit 21 includes a plurality of electric double layer capacitors between the wiring 13 and the ground. The capacitors 22 are connected in series, and each of the capacitors 22 is individually connected. A resistor 23 having a high resistance value is connected in parallel. The relay circuit 31 similarly includes the wiring 14 A plurality of electric double layer capacitors 32 are connected in series between the A high resistance resistor 33 is connected in parallel to each of the capacitors 32. . In addition, in the preceding stage of the charging circuit 21 of the wiring 13, there is no A backflow prevention diode 24 that allows only inflow is interposed. Where the conde The resistors 22 and 32 have resistors 23 and 33 having the same resistance value connected in parallel. Therefore, a uniform voltage is applied and the battery is charged. Electric double layer capacitors are generally Has a withstand voltage of 2.3V, so that you can obtain the necessary charging voltage and capacity as needed. May be connected in series, or may be connected in parallel so as to have a required capacity.

[0015]   From this, the charging circuit 21 is always connected to the secondary battery side (power input terminal 10a side). In the short-circuited state, the same voltage corresponding to the power supply voltage is applied to each of the capacitors 22. Is constantly applied to immediately complete charging. This charging circuit 21 has a switching contact 11b. As long as is open, the current will be reversed even if the voltage on the secondary battery side drops. It is prevented by the diode 24 that it will flow, and the switching contact 11b is shared. When short-circuited with the communication contact 11c, current can be supplied from the capacitor 22. It

[0016]   On the other hand, the relay circuit 31 is provided with a secondary battery or a secondary battery depending on the switching operation of the changeover switch 11. The power supply voltage from the charging circuit 21 is applied, and the same voltage according to the power supply voltage Are applied to each of the capacitors 32. Therefore, the relay circuit 31 is not connected. Normally, charging is completed by the power supply from the secondary battery (power input terminal 10a side), The charging voltage also fluctuates due to fluctuations in the power supply voltage. Even if the power supply from these devices is interrupted, the device itself is always in a short circuit by itself (power output Electric power can be supplied to the force terminal 10b side).

Here, when the charging circuit 21 and the relay circuit 31 discharge from the capacitor of the electrostatic capacitance C farad at the output voltage V volt and the maximum current A ampere / hour, the output voltage V of this capacitor is e ^−αt. Since it decreases along the curve of, the supply voltage to the apparatus main body side (the integrated value of the output voltage of the capacitor) decreases. At this time, the DC-DC converter supplies a stable power supply voltage to the device main body, but the time t during which the power supply voltage can be supplied from the charging circuit 21 or the relay circuit 31 to the device main body is constant resistance. Assuming that the output voltage at the start of discharging the capacitor is V0 volt, the minimum voltage when the DC-DC converter is stopped is V1 volt, and the load resistance value (= V / A) of the capacitor is R ohms, the following equation is obtained. Can be calculated from That is, the electrostatic capacitance C of the capacitors 22 and 32 of the charging circuit 21 and the relay circuit 31 may be calculated back from the following equation in consideration of the time required to maintain the power supply to the apparatus body. t [sec] = − C [F] × R [Ω] × In (V1 / V0)

[0018]   In addition, the wiring 13 has an operation detection alarm circuit (output circuit) that monitors the operation of the charging circuit 21. 16) is connected to the output circuit 16 and the output circuit 16 is connected to, for example, the charging circuit 21. Discharge (operation) is present when the voltage between cells is measured and a voltage drop is confirmed after charging is completed. Warning signal (detection signal) that starts necessary processing when power is consumed Output from the output terminal 16a to the apparatus main body side. Here, this alarm signal is Detection signal sent from the voltage drop detection circuit 15 to drive the spare switch 11 May be simultaneously output to the apparatus main body side.

[0019]   Next, the operation of the power supply auxiliary circuit 10 will be described. First, rechargeable batteries for electronic devices When set, the switching contact 11a of the changeover switch 11 and the common contact 11c are short-circuited. In the normal state, power is supplied from the secondary battery to the main body of the device through the wiring 12. At the same time, the capacitor 32 of the relay circuit 31 is charged and the wiring 13 Then, the capacitor 22 of the charging circuit 21 is also charged.

[0020]   After this, the electric power charged in the secondary battery is consumed, and the voltage approaches the low voltage state. If the secondary battery comes off for some reason, the power supply voltage from the secondary battery suddenly increases. Since it drops sharply, the DC-DC converter suddenly stops operating and returns to the main unit. Power supply is cut off. Here, even if the power supply voltage from the secondary battery drops, The diode 24 prevents the electric power charged in the path 21 from flowing back to the secondary battery side. Be stopped.

[0021]   At this time, the drop in the power supply voltage at the power supply input terminal 10a is detected by the voltage drop detection circuit 15. Detected, the detection signal is sent to the changeover switch 11, and short-circuit with the common contact 11c The charging circuit is switched from the switching contact 11a to the switching contact 11b. The electric power charged in 21 is supplied to the apparatus main body through the wiring 14.

[0022]   Therefore, the power supply from the secondary battery side is suddenly cut off in the device body. In the case of charging, the charging circuit 21 receives the initial power supply voltage that enables normal operation. Can be taken. At the same time, the power supply from the charging circuit 21 is started for the device main body. Then, the discharge of the charging circuit 21 is detected by the operation detection circuit 16 and an alarm signal is issued. When the electronic device is a data processing device or the like, First-aid measures such as temporary storage of in-process data can be executed. The device book In the body, sound a buzzer to inform the user of the exhaustion of the secondary battery. You can also Since the charging circuit is composed of a large-capacity capacitor, for example, It is possible to sufficiently secure the time required for the first aid of about 2 minutes.

[0023]   In this case, the power supply for supplying power to the device body is switched from the secondary battery to the charging circuit 21. However, since the relay circuit 31 is directly connected to the device body, the switching switch While the switching operation of the switch 11 (about several hundred msec), It is possible to avoid the so-called momentary power failure of the device body that is supplied from the relay circuit 31. You can avoid it. It should be noted that the changeover switch 11 can be provided without providing the relay circuit 31. When a mechanical electromagnetic relay is used for the switching contacts 11a and 11b and the common contact 11 The connection with c is temporarily cut off, and a solid state semiconductor switch such as MOS is used. In that case, voltage fluctuation is likely to occur, and the device body may momentarily stop.

[0024]   In this way, the charging circuit 21 has sufficient power to perform the required operation in an emergency. It is only necessary to charge the relay circuit 31 and the relay circuit 31 is turned off. It is only necessary to be able to supply sufficient power during the replacement operation, so increase the capacity of each. You don't have to. The charging circuit 21 and the relay circuit 31 are electric double layer capacitors. Since 22 and 32 are connected in series, it can be made compact, and relay The circuit 31 can have a smaller capacity than the charging circuit 21.

[0025]   That is, in the present embodiment, the power supply voltage of the secondary battery is necessary for the operation of the device body. Even if the voltage drops below the required voltage, the power supply path to the main unit is fully charged. It is possible to switch to the electric circuit 21 side smoothly and continue to supply electric power. Even if the power supply from the computer is cut off, the main body of the device cannot be immediately disabled. Yes. Therefore, by mounting the compact power supply auxiliary circuit 10, reliability can be improved. To ensure that the first aid function operates properly, supply power to the device for a high and necessary time. You can

[0026]

[Effect of device]

  According to the present invention, when the secondary battery becomes lower than the set voltage, The power supply path is switched to the charged charging circuit side, so it is necessary to replace the secondary battery The power can be suddenly supplied to the main body of the device. Therefore, the power supply from the secondary battery Even if it is not supplied, it does not immediately disable the operation, and it is highly reliable in the device body. It can be powered to function.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a power supply auxiliary circuit according to the present invention, and is a block diagram showing the overall configuration thereof.

[Explanation of symbols]

10 power supply auxiliary circuit 11 Changeover switch 15 Voltage drop detection circuit 16 Motion detection alarm circuit 21 Charging circuit 22,32 Electric Double Layer Capacitor 23,33 resistance 24 Backflow prevention diode 31 Relay circuit

Claims (5)

[Scope of utility model registration request] 1. A power supply auxiliary circuit arranged between a secondary battery for supplying electric power to an apparatus main body and the apparatus main body, wherein one or more of which are charged by applying a power supply voltage from the secondary battery. The charging circuit consisting of the capacitor, the changeover switch that switches the power supply path to the device body side to either the secondary battery or the charging circuit, and the power supply voltage that the secondary battery supplies to the device body side is measured in advance. A power supply auxiliary circuit provided with a detection circuit for switching the power supply path to the apparatus main body by the changeover switch from the secondary battery side to the charging circuit side when it is detected that the voltage is lower than the set voltage. . 2. A power supply auxiliary circuit arranged between a secondary battery for supplying electric power to the device body and the device body, wherein one or more of which are charged by applying a power supply voltage from the secondary battery. The charging circuit consisting of the capacitor, the changeover switch that switches the power supply path to the device body side to either the secondary battery or the charging circuit, and the power supply voltage that the secondary battery supplies to the device body side is measured in advance. Between the detection circuit that switches the power supply path from the secondary battery side to the charging circuit side by the changeover switch to the charging circuit side when it detects that the voltage is lower than the set voltage, and between the changeover switch and the apparatus main body side. And a relay circuit including one or more capacitors that are charged by being applied with a power supply voltage from a secondary battery,
A power supply auxiliary circuit, comprising: an output circuit that monitors whether or not the charging circuit is discharged and outputs a detection signal when the discharge is confirmed. 3. The power supply auxiliary circuit according to claim 1, wherein the charging circuit is configured by using an electric double layer capacitor. 4. The power supply auxiliary circuit according to claim 1, wherein the charging circuit is configured by connecting resistors having the same resistance value in parallel for each capacitor. 5. The power supply auxiliary circuit according to claim 1, wherein a backflow prevention diode is provided between the charging circuit and the secondary battery.