JP2009278763A - Charger and charging method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an easy-to-use charger for a portable telephone. <P>SOLUTION: The charger includes: a power terminal for the telephone; a power terminal for an AC adapter; an in-charger secondary battery; a boosting part; a protection circuit which controls over-discharging and/or overcharging; and an in-charger secondary battery charging current control circuit. When the portable telephone, the charger and the AC adapter are connected to one another in series, the charging of the in-charger secondary battery by the AC adapter is started after an in-telephone secondary battery is fully charged. There is arranged the protection circuit which detects a rise in the temperature of the in-charger secondary battery and/or the swell of a vessel, and stops its operation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a charger and a charging method for charging a mobile phone.

  The number of mobile phones sold in Japan exceeded 90 million units, making it a necessity for modern life. The functions are added year by year and are becoming more and more multifunctional, and there is no end to them such as mail transmission / reception, music player, game player, watching TV broadcast, wallet mobile phone, video shooting.

  By the way, the mobile phone is driven by a built-in secondary battery. In order to make the usable time as long as possible, a lithium battery with high energy density is used. If the standby time is just waiting for a phone call, it can take about 300 hours. However, the continuous call time is about 2 hours. Also, if you use it for enjoying games, watching TV broadcasts, creating e-mails, and sending / receiving e-mails, the available call time will be reduced accordingly.

  Therefore, the capacity of the battery may be reduced at an unexpected place while going out, making it impossible to make a call. In such cases, you often don't have a charger, and you won't be able to get in touch for a while, which hinders your work. Even when a charger (which obtains an AC power supply and converts it to DC power) is possessed, there is a case where the power supply from the power outlet cannot be obtained as desired and charging cannot be performed. Then, even if you carry your mobile phone with you, the convenience will be lost.

  To deal with such a situation, emergency chargers for mobile phones that combine primary batteries (chemical batteries that can only discharge DC power, disposable batteries) and charging circuits have been sold at convenience stores and consumer electronics mass retailers. .

  Patent Document 1 discloses a charge / discharge protection circuit capable of protecting a secondary battery by detecting overcharge, overdischarge, discharge overcurrent, or charge overcurrent, and a battery pack incorporating the charge / discharge protection circuit. It is disclosed. Each detection circuit is provided to control on / off of the discharge control FET (field effect transistor, field effect transistor) and charge control FET.

Patent Document 2 discloses a charger capable of simultaneously charging a battery pack attached to an electric device and a spare battery pack not attached to the electric device while charging an inexpensive battery pack not including a charging circuit. Is disclosed. A first power supply terminal for charging the battery pack mounted on the mobile phone; a second power supply terminal for charging the spare battery pack alone; and a charging circuit for controlling charging of the spare battery pack. The on / off control of the charging operation of the spare battery pack is performed based on the magnitude of the input voltage to the charging circuit.
JP 2002-176730 A JP 2003-164070 A

  The mobile phone charger that combines the above-described primary battery and charging circuit is large and heavy because the primary battery is used. Although the portion of the charging circuit can be reused, the primary battery is disposable, so that the charging circuit may also be discarded together with the battery, which is undesirable for the global environment.

  The protection circuit disclosed in Patent Document 1 cannot detect that the secondary battery expands for some reason.

  The charger disclosed in Patent Document 2 makes it possible to charge both the secondary battery and the spare battery inside the mobile phone by a single charging operation. However, when the capacity of the mobile phone becomes insufficient, it is necessary to open the back cover of the mobile phone and replace the battery. The daily operation is a time-consuming operation. In addition, frequent replacement of the battery increases the frequency of opening and closing the back cover, which increases the lock of the back cover and leads to accidents such as loss due to falling.

  An object of the present invention is to provide an easy-to-use mobile phone charger.

  The charger according to the present invention uses a secondary battery instead of the primary battery, whereas the conventional emergency charger is a combination of a primary battery and a booster circuit. In order to charge the secondary battery in the charger, an AC adapter (charger) attached to the mobile phone is used. A connector for AC power supply attached to the mobile phone, a secondary battery, a secondary battery charging power supply unit (protection circuit), a charge control unit, a booster unit (DC-DC converter), and a mobile phone connection connector.

  The charger according to claim 1 includes a power terminal for a telephone connected to a power terminal of a mobile phone, and charging for charging a secondary battery in the telephone built in the mobile phone through the power terminal for the telephone The charger has a secondary battery in the charger and a booster that compensates for a voltage drop caused by discharge of the secondary battery in the charger, and the secondary battery in the telephone The battery is boosted to a voltage suitable for charging and supplied to the telephone power terminal for charging.

  The charger according to claim 2 is the charger according to claim 1, wherein an AC adapter attached to the mobile phone is connected to an AC adapter power terminal for supplying power to the mobile phone. When charging the secondary battery in the charger by supplying a DC current supplied from the AC adapter via the adapter power terminal and the AC adapter power terminal to the secondary battery in the charger, The battery pack further includes a protection circuit for controlling overcharge, and the secondary battery in the charger is charged by an AC adapter attached to the mobile phone.

  The charger according to claim 3 is the charger according to claim 2, further comprising an in-charger secondary battery charging current control circuit for controlling a charging current for the in-charger secondary battery, When the mobile phone, the charger, and the AC adapter are connected in series, priority is given to charging the secondary battery in the telephone by the AC adapter, and the AC battery is fully charged after the secondary battery in the telephone is fully charged. The charging of the secondary battery in the charger by the adapter is started.

  The charger according to claim 4 is the charger according to any one of claims 1, 2, or 3, and detects an increase in temperature due to an abnormality of the secondary battery in the charger to operate the circuit. It further has a temperature rise detection protection circuit to be stopped.

  The charger according to claim 5 is the charger according to any one of claims 1, 2, or 3, and detects the expansion of the container due to abnormality of the secondary battery in the charger to operate the circuit. It further has a container expansion detection protection circuit to be stopped.

  The charging method according to claim 6 is connected to a power terminal for a telephone connected to a power terminal of a mobile phone and an AC adapter power terminal for an AC adapter attached to the mobile phone to supply power to the mobile phone. Power adapter for AC adapter, secondary battery in charger, and booster that compensates for voltage drop caused by discharge when the secondary battery in charger is charged in secondary battery in telephone set built in mobile phone And controlling the overdischarge / overcharge when charging the secondary battery in the charger by supplying the DC current supplied from the AC adapter to the secondary battery in the charger through the power terminal for the AC adapter. Using a charger having a protection circuit for controlling and a secondary battery charging current control circuit for controlling a charging current for the secondary battery in the charger, the mobile phone, the charger, and the AC adapter A charging method when connected in series, wherein the charging operation from the secondary battery in the charger to the secondary battery in the telephone is stopped by stopping the function of the boosting unit, and the secondary battery in the charger The charging current control circuit stops the charging current from the AC adapter to the secondary battery in the charger, and passes the charging current from the AC adapter to the mobile phone side. Recharging the in-telephone secondary battery to perform charging by the AC adapter, and detecting in-phone secondary battery full charge by detecting that the in-telephone secondary battery is fully charged by the in-telephone secondary battery charging step And charging the secondary battery in the charger by the AC adapter after the full charge of the secondary battery in the telephone is detected by the step and the secondary battery full charge detection step in the telephone. Consisting of a charger in the secondary battery charging initiating.

  Since the present invention is configured as described above, if the AC adapter attached to the mobile phone can be used, the secondary battery in the phone can be connected by connecting the mobile phone-the charger according to the present invention-AC adapter in series. It is convenient to use a mobile phone while charging the secondary battery in the charger together. In particular, by providing a circuit that controls the charging current to the secondary battery in the charger, without the user being aware of switching between charging the secondary battery in the telephone and charging the secondary battery in the charger, Appropriate charging is possible.

  It can be safely used with multiple protection circuits such as overcurrent control, internal temperature rise protection, and abnormal protection of secondary battery in the charger (detection of expansion in the event of a malfunction to stop explosion)

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic view showing a state in which a charger 20 according to the present invention is positioned between a mobile phone 10 and an AC adapter 30 thereof. The AC adapter 30 is an AC adapter that is attached when the mobile phone 10 is purchased. The AC adapter 30 obtains power from a home AC power source, converts it into direct current, and the secondary battery 11 in the phone inside the mobile phone 10. (Not shown) is charged. At this time, a protection circuit for protecting the in-phone secondary battery 11 from overdischarge / overcharge is not provided inside the in-phone secondary battery 11. Inside the mobile phone 10, a circuit for controlling the charging current and a protection circuit for protecting from overdischarge / overcharge are provided.

  In a mobile phone in Japan, a connector that connects the mobile phone 10 and the AC adapter 30 has a 10-pin or 18-pin connector. Hereinafter, in this specification, a terminal for connecting to the AC adapter on the mobile phone side is referred to as an AC adapter power terminal 14, and a terminal for connecting to the mobile phone on the AC adapter side is an anti-phone power terminal 32. Call it. The telephone power terminal 22 is provided on the side connected to the mobile phone of the charger according to the present invention, and the power terminal 24 for AC adapter is provided on the side connected to the AC adapter. Thereby, the mobile phone 10, the charger 20, and the AC adapter 30 can be connected in series as shown in FIG.

  As shown in FIG. 1, not only when three devices are connected in series, but the charger 20 according to the present invention is connected only to the mobile phone 10 and the secondary battery 21 in the charger can The secondary battery 11 can also be charged. Further, the charger 20 according to the present invention is connected only to the AC adapter 30 and an AC power supply is used to connect the secondary battery 21 in the charger (secondary connected to BATT + and BATT− in FIGS. 5 and 6 described later). Battery) can also be charged.

  FIG. 2 is a block diagram of a charger according to the present invention. The current discharged from the in-charger secondary battery 21 is boosted by the booster 23 and supplied to the telephone 10 via the telephone power terminal 22 to charge the in-phone secondary battery 11. In the circuits of FIGS. 5 and 6 to be described later, the boosting unit 23 is a portion constituted by control elements Q7, Q8, Q11, a coil L1, capacitors C4, C5, resistors R11, R12, a diode D3, and an integrated circuit U2. is there.

The charging current supplied from the AC adapter 30 to the AC adapter power terminal 24 reaches the secondary battery 21 in the charger via the temperature rise detection protection circuit 27 and the secondary battery charging current control circuit 26 in the charger. Charge it. Further, regarding the charging of the secondary battery 21 in the charger, the container expansion detection protection circuit 28 and the control unit 29 are also involved, and when necessary, the charging operation is stopped. Here, the temperature rise detection protection circuit 27 is called a polyswitch, and the resistance value becomes extremely large due to the temperature rise, thereby stopping the current flow.
The container expansion detection protection circuit 28 employs a push button switch here, mechanically detects that the secondary battery 21 in the charger is expanded, and transmits the information to the control unit 29. Stop charging operation. The charging operation is also stopped when overcharge / overdischarge is detected by the circuit. The in-charger secondary battery charging current control circuit 26 is a circuit including a control element Q1 and a diode D2 in the circuits of FIGS. The control unit 29 is a circuit configured by an integrated circuit U1 in the circuits of FIGS.

  The operation when both the AC adapter 30 and the mobile phone 10 are connected to the charger 20 is complicated. Roughly speaking, first, a charging current from the AC adapter 30 is first passed, and then delivered to the mobile phone 10 as it is, and the secondary battery 11 in the phone is charged. When the full charge of the secondary battery 11 in the telephone is detected, the charging operation of the secondary battery in the charger is started. Details will be described later with reference to the detailed circuit diagram of FIG.

  FIG. 3 is a schematic cross-sectional view showing the internal structure of the charger according to the present invention. The secondary battery 21 in the charger is considered to have a shape that is essentially a rectangular parallelepiped, but when the container expands for some reason, it is assumed that the central portion swells and approaches an ellipsoid. The cross section is shown. A mechanical push button switch is provided on the circuit board 40 as a container expansion detection protection circuit 28 so that it can be detected if the secondary battery 21 in the charger is expanded. The support column 41 supports the secondary battery 21 in the charger.

  FIG. 4 is a perspective view showing the external appearance of the charger according to the present invention. In the charger according to the present invention, when the charging is completed or when the protection circuit is operated, the white LED is lit by pressing the button SW2 provided in the main body of the present invention and the LED that lights up in a color corresponding to the state. It also comes with a function that can be used as a simple lighting. The white LED lighting switch 42 in FIG. 4 is provided outside the charger 20 and turns on the white LED 43 when pressed when the user wants light in a dark place. The telephone power terminal 22 and the AC adapter power terminal 24 are provided in a well-balanced position when connecting to the mobile phone 10 and the AC adapter 30.

  FIG. 5 is a circuit diagram of the charger when the connector has 10 pins. FIG. 6 is a circuit diagram of the charger when the connector has 18 pins. Hereinafter, the operation of the charger according to the present invention will be described with reference to FIGS. 5 and 6.

[Charging operation for the secondary battery in the charger of the charger according to the present invention (cell phone is not connected)]
By connecting the AC adapter 30 attached to the mobile phone 10 to the AC adapter power terminal 24 of the charger 20 according to the present invention, the charging operation to the secondary battery 21 in the charger is started. The power supplied from the AC adapter 30 is supplied to the in-charger secondary battery 21 through the control element Q1 and the diode D2 in the in-charger secondary battery charging current control circuit 26 of the charger 20 according to the present invention. Charge.

The control unit U1 monitors the voltage between VDD and VSS, monitors the charging voltage and discharging voltage for the secondary battery 21 in the charger, and supplies the control element Q9 connected to the charging control terminal CO and the discharging control terminal DO. The connected control element Q10 is controlled to prevent overcharging and overdischarging. In the normal state, both Q9 and Q10 are in a conducting state. Depending on the overcharge or overdischarge situation, the respective control elements are turned off and the circuit is shut off.
Further, the charging current is controlled based on the voltage generated at the resistor R9 connected to the current control terminal VM, and when it is detected that the overcurrent is detected, the discharge control element Q10 is turned off to control the overcurrent.

Further, as a protection device, a protection switch PL1 (temperature rise detection protection circuit 27 in FIG. 2) whose electric resistance greatly increases with temperature is provided in the power supply unit, and the battery of the present invention is detected due to abnormality of the secondary battery in the charger or the circuit. When the internal temperature of the charger casing increases, the secondary battery in the charger is disconnected from the circuit.
When the temperature decreases, the electrical resistance of the protective switch PL1 decreases, and power is automatically supplied.

  Further, a protection switch SW1 (a container expansion protection circuit 28 in FIG. 2) configured by a push button switch is installed so as to be sandwiched between the circuit board 40 and the secondary battery 21 in the charger. If for any reason the secondary battery 21 in the charger becomes abnormal and the container expands, the protection switch SW1 physically detects the expansion of the secondary battery in the charger (the secondary battery is It is detected that the outside of the container pushes the push button mechanically), the power supply to the secondary battery 21 in the charger is stopped, and the battery explosion is protected in advance.

[Charging operation from the charger according to the present invention to the secondary battery in the mobile phone]
When the AC adapter 30 cannot be used when away from home, the charger 20 according to the present invention and the mobile phone 10 are connected to charge the mobile phone 10.
Power is supplied from the in-charger secondary battery 21 to the coil L1 of the booster 23, and the voltage is increased to a voltage suitable for charging the in-phone secondary battery 11 built in the mobile phone 10 to perform charging.

When the charger 20 according to the present invention is connected to the mobile phone 10 by connecting the power terminal 22 to the mobile phone 10 and the AC adapter power terminal 14 on the mobile phone 10 side, a predetermined pin (of the 10-pin connector) of the mobile phone 10 is connected. 5 in the right connector in FIG. 5 and 16 pins in the right connector in FIG. 6 in the case of the 18-pin connector), the power is supplied to the charging circuit built in the mobile phone 10 itself, and the minus Current flows between the pin 1 on the side.
At this time, since the current is supplied to the resistor R12 via the resistor R11 and the control element Q11, the ON-OFF terminal of the integrated circuit U1 of the booster 23 is set ON by the voltage generated at the resistor R12, and the booster 23 operates. To start.
The booster unit 23 is provided with a dedicated voltage / current control circuit, whereby the mobile phone 10 can be charged safely. The role of the booster is to compensate for the voltage drop accompanying the discharge of the secondary battery 21 in the charger and to supply a stable voltage to the mobile phone.

[When a mobile phone, a charger according to the present invention, and an AC adapter are connected in series]
In this case, the mobile phone 10 is charged directly from the AC adapter 30 through the charger 20 according to the present invention.
Specifically, the power supplied from a predetermined pin of the AC adapter power terminal 24 (in the case of a 10-pin connector, 5 pins of the left connector in FIG. 5 and in the case of an 18-pin connector, 16 pins of the left connector in FIG. 6) Through the diode D1, the mobile phone 10 is connected via the corresponding pin of the telephone power terminal 22 (in the case of a 10-pin connector, the pin 5 on the right side of FIG. 5 and in the case of an 18-pin connector, the 16 pin on the right side of FIG. 6). Supplied to.

  At this time, the control element Q7 detects the voltage supplied via the mobile phone charger, and controls the ON-OFF terminal of the booster to stop the operation of the booster. Further, while the secondary battery 11 in the telephone of the mobile phone is being charged, the control element Q1 is turned off because the diode D4 is connected to the negative side, and the secondary battery 21 in the charger of the charger 20 according to the present invention is charged. Power supply is also stopped.

Charging of the in-phone secondary battery 11 of the mobile phone 10 is performed by a charging circuit built in the mobile phone 10. When the in-phone secondary battery 11 is fully charged, the charging circuit built in the mobile phone is cut off.
As a result, the current between the connector 5 pin and 1 pin on the right side of FIG. 5 (between the connector pin 16 and 1 pin on the right side of FIG. 6) stops, the diode D4 is cut off from the minus side, and the control element Q1 is turned on. It becomes the state which can charge with respect to the secondary battery 21 in the charger of the charger 20 of.

The controller 29 (a circuit including the integrated circuit U1) starts charging the secondary battery 21 in the charger of the charger 20 of the present invention as necessary.
When the secondary battery 21 in the charger is also fully charged, the charging control element Q9 of the control unit 29 is turned off and the charging operation is stopped.

If no control is performed, even when the in-phone secondary battery 11 is charged, charging of the in-charger secondary battery 21 is started at the same time, and the in-phone secondary battery 11 and the in-charger secondary battery are also started. Depending on the usage state of the two secondary batteries 21, there is a possibility that the charging operation is different and which is preferentially charged becomes undefined. Also, the current may flow up to the limit.
Therefore, in consideration of the allowable current of the AC adapter 30, the charging current for the secondary battery 21 in the charger 20 according to the present invention is given priority to the secondary battery built in the mobile phone as described above. If the control element Q1 is turned off as described above, the AC adapter 30 is charged by controlling and charging the current value to be smaller than the normal current value (about 10 mA) through the resistor R6 connected in parallel with Q1. This prevents overloading.

  Similar to a mobile phone, a secondary battery is built in, and the present invention can be applied to general electronic devices that charge an internal secondary battery by connecting an AC adapter.

It is a schematic diagram which shows the state which has located the charger which concerns on this invention in the middle of a mobile telephone and its AC adapter. It is a block diagram of the charger which concerns on this invention. It is a cross-sectional schematic diagram which shows the internal structure of the charger which concerns on this invention. It is a perspective view which shows the external appearance of the charger which concerns on this invention. It is a circuit diagram of the charger when the connector has 10 pins. It is a circuit diagram of a charger when the connector has 18 pins.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Mobile phone 11 Secondary battery 14 in telephone, 24 AC adapter power terminal 20 Charger 21 Secondary battery 22 in charger 32, Telephone power terminal 23 Booster 25 Protection circuit 26 Secondary battery charging current control in charger Circuit 27 Temperature rise detection protection circuit 28 Container expansion detection protection circuit 29 Control unit 30 AC adapter 40 Circuit board 41 Post 42 White LED lighting switch 43 Status display and simple illumination LED
C1, C2, C3, C4, C5 Capacitors D1, D2, D3, D4, D5, D6 Diode L1 Coil LED1, LED2
PL1 Polyswitch Q1, Q3, Q4, Q5, Q7, Q8, Q9, Q10, Q11 Control element R1, R2, R3, R4, R6, R8, R9, R10, R11, R12 Resistor SW Push button switch U1, U2 Integrated circuit

Claims (6)

A battery charger having a telephone power terminal connected to a power terminal of a mobile phone, and charging a secondary battery in the telephone built in the mobile phone via the telephone power terminal,
Inside the charger,
A secondary battery in the charger;
A voltage boosting unit that compensates for a voltage drop associated with the discharge of the secondary battery in the charger, and boosts the voltage to a voltage suitable for charging the secondary battery in the telephone and supplies power to the power terminal for the telephone. Charger that performs charging. The charger according to claim 1,
An AC adapter power terminal connected to an AC adapter power terminal for supplying power to the mobile phone by an AC adapter attached to the mobile phone;
When charging the secondary battery in the charger by supplying the DC current supplied from the AC adapter to the secondary battery in the charger via the power terminal for the AC adapter, overdischarge / overcharge is controlled. A protective circuit,
The charger which charged the secondary battery in the said charger with the AC adapter attached to the said mobile telephone. The charger according to claim 2,
A battery charging current control circuit for controlling the charging current for the secondary battery in the charger; and when the mobile phone, the charger and the AC adapter are connected in series, Charger of the secondary battery by the AC adapter is prioritized, and charging of the secondary battery in the charger by the AC adapter is started after the secondary battery in the telephone is fully charged.   4. The charger according to claim 1, further comprising a temperature rise detection protection circuit that detects a temperature rise due to abnormality of the secondary battery in the charger and stops operation of the circuit. 5. A charger characterized by that.   4. The charger according to claim 1, further comprising a container expansion detection protection circuit that detects the expansion of the container due to abnormality of the secondary battery in the charger and stops the operation of the circuit. A charger characterized by that. A power terminal for a telephone connected to a power terminal of a mobile phone, a power terminal for an AC adapter connected to an AC adapter power terminal for an AC adapter attached to the mobile phone to supply power to the mobile phone, and a charger A secondary battery, a booster that compensates for a voltage drop caused by discharge when the secondary battery in the charger charges the secondary battery in the telephone built in the mobile phone, and the power adapter for the AC adapter A protection circuit that controls overdischarge / overcharge when supplying a DC current supplied from the AC adapter to the secondary battery in the charger to charge the secondary battery in the charger; Charging method when the mobile phone, the charger and the AC adapter are connected in series using a charger having an in-charger secondary battery charging current control circuit for controlling a charging current for the secondary battery There,
By stopping the operation of the boosting unit, the charging operation from the secondary battery in the charger to the secondary battery in the telephone is stopped, and from the AC adapter by the operation of the secondary battery charging current control circuit in the charger. The secondary battery in the telephone which performs charging by the AC adapter of the secondary battery in the telephone by stopping the charging current to the secondary battery in the charger and passing the charging current from the AC adapter to the mobile phone side. Battery charging step;
A secondary battery full charge detection step in the telephone for detecting that the secondary battery in the telephone is fully charged by the secondary battery charge step in the telephone;
Charger secondary battery charging step for starting charging of the secondary battery in the charger by the AC adapter after the full charge of the secondary battery in the telephone is detected by the secondary battery full charge detection step in the telephone A charging method consisting of

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