KR20080028170A - Apparatus and method for battery charging - Google Patents

Abstract

An apparatus and a method for battery charging are provided to expand an application range of a battery by using the batteries of different charge voltages in one system through selective conversion of a voltage level of power supplied from a power adapter. An apparatus for battery charging includes a plurality of batteries(10), an embedded controller(20), a system control unit(30), an input/output control hub(40), and a charge unit(50). The plurality of batteries have different charge voltages from each other. The embedded controller receives the charge voltage of the battery through communication with each of the batteries. The system control unit generates a charge voltage control command for the charge voltage of the battery. The input/output control unit determines a voltage level of a charge voltage control signal according to the charge voltage control command. The charge unit selectively converts supplied power into a voltage level of the charge voltage according to the voltage level of the charge voltage control signal so as to charge the battery with the converted voltage.

Description

Battery Chargers and Methods {APPARATUS AND METHOD FOR BATTERY CHARGING}

1 is a block diagram of a battery charging apparatus according to an embodiment of the present invention,

2 is a flowchart illustrating a battery charging method according to an exemplary embodiment of the present invention.

`` Explanation of symbols for main parts of drawings ''

10: battery 20: embedded controller

30: system control unit 40: input / output control hub

50: charging unit 52: charging circuit

54: voltage conversion section 56: field effect transistor

R1, R2, R3: Resistor D1: Diode

The present invention relates to a battery charger, and more particularly, to a battery charger and a method for charging a battery having a different charging voltage.

Conventional portable devices, such as notebooks (notebooks), mobile wireless phones, and the like use power charged in a rechargeable battery (hereinafter, referred to as a battery) as a main operating power source.

Such a portable device cannot operate the portable device with a battery unless it is charged with a voltage output from a power adapter that converts external AC power into a DC power when the battery voltage is discharged below a certain level. Therefore, only charging at a constant cycle.

In the case of a notebook, it is configured to charge the battery installed in the notebook by detecting it when an external voltage is supplied from the power adapter, and in the case of a mobile wireless telephone is a case of combining the battery in a separate charger to charge.

Such a battery is being used by applying a battery having a higher charging voltage than a general charging voltage in order to increase the charging capacity as the portable device has a large capacity, multifunction, and increased power consumption. For example, when two bundles of three battery cells connected in series are used in parallel, and the charging current is 2600mAh, the charging capacity of the first battery having the charging voltage of 4.2V is 65.62Watt. On the other hand, the charge capacity of the second battery, which is recently manufactured to be 4.35V, is 67.86Watt. When the average power consumption per hour is 20 Watts, the usage time of the first battery is 3.276 hours and the usage time of the second battery is 3.393 hours. Accordingly, when the second battery having the high charging voltage is used, the capacity and the use time may be increased by about 3.5%.

However, since a voltage value supplied to a charging circuit is fixed in a conventional portable device, a battery having a different charge voltage level from a power supplied from a power adapter cannot be used. In addition, when a battery having a low charging voltage is mounted and charged in a portable device to which a battery having a high power level of a power source is applied, there is a problem in that the battery is damaged and broken.

Accordingly, an object of the present invention is to provide a battery charging device and method for selectively charging a battery having a different charging voltage in one system.

According to a feature of the present invention for achieving the above object, the present invention provides a plurality of batteries having different charging voltages, a voltage conversion unit for selectively generating a supply power for the charging voltage of each battery, And a charging circuit for charging the battery by the generated supply power.

According to another aspect of the present invention, a plurality of batteries having different charging voltages, an embedded controller that communicates with each of the batteries to receive the charging voltage of the battery, and a charging voltage control command for the charging voltage are provided. A system control unit for generating a power supply; It is configured to include a charging unit for selectively converting to charge the battery.

The charging unit charges the battery using a voltage conversion unit for selectively converting the voltage level of the supply power supplied to the battery according to the voltage level of the charging voltage control signal, and the supply power converted from the voltage conversion unit. It is preferable to include a charging circuit.

The voltage conversion unit includes a first resistor and a second resistor configured in series between the supply power supply and the ground potential line to divide the supply power, and a third resistor and a switch connected in parallel with the second resistor. It is preferred to be configured.

Preferably, the switch is a field effect transistor that opens and closes according to the voltage level of the charging voltage control signal.

The field effect transistor is preferably driven on when the voltage level of the charge voltage control signal is 'high' level and off when the voltage level of the charge voltage control signal is 'low' level.

It is preferable that the said charge voltage is 4.2V or 4.35V.

In addition, according to another feature of the invention, the present invention comprises the steps of receiving a charging voltage of a plurality of batteries having different charging voltage, generating a supply power for charging the battery according to the received charging voltage and And charging the battery using the generated supply power.

The present invention may further include generating a control command for the charging voltage and determining a voltage level of the charging voltage control signal according to the control command.

The supply power is preferably determined by the voltage level distributed through different current paths formed by the switches turned on / off by the charging voltage control signal.

The present invention having the configuration as described above charges the battery by converting the voltage level of the power supply in accordance with the charging voltage of the battery. Accordingly, the present invention extends the battery utilization range by selectively using batteries having different charging voltages.

Hereinafter, exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

1 is a block diagram of a battery charging apparatus according to a preferred embodiment of the present invention.

First, a battery 10 for supplying power to a portable device body is provided. The battery 10 is a rechargeable battery that is commonly used, for example, a lithium ion battery widely used in a notebook or the like. The battery 10 includes a gauging circuit (not shown) that detects charged voltages, currents, and temperatures of a plurality of built-in battery cells, and calculates available capacity, charge voltage, charge current, capacity information, It is preferable that the battery is a smart battery including Ipyrom (not shown) in which important parameters such as a charging method and an assembly date are stored. The values detected by the gauging circuit and the information stored in the ypyrom are called battery information. Among them, the charging voltage of the battery cell will be described using a case of 4.2V or 4.35V.

In addition, an embedded controller 20 is provided to communicate with the battery 10 to receive the battery information and to control the charging circuit 52 for charging the battery 10 according to the battery information. The embedded controller 20 transfers the charging voltage from the battery information to the system controller 30 to be described later. The embedded controller 20 and the battery 10 are connected to a system management bus (hereinafter referred to as SMBus) to enable data communication. The embedded controller 20 generates a charging request signal when the battery information received from the battery 10 is not a predetermined full charge state, and when the battery information is the full charge level, the embedded controller 20 sends the charging circuit 52 to the charging circuit 52. Provide a charge interruption signal. Thus, the charging circuit 52 receiving the charge blocking signal cuts off the power supplied to the battery 10 to prevent overcharging of the battery 10.

Next, a system control unit 30 operated by an operating system is provided. The system controller 30 generates a charge voltage control command for the charge voltage transmitted from the embedded controller 20. The system controller 30 includes a power management module (not shown) for monitoring the battery 10 to manage power of the battery and an EC for transmitting a signal from the embedded controller 20 to the power management module. EC firmware (not shown) and a system BIOS for controlling basic input / output of the system may be provided. It should be noted that the power management module, the system BIOS, and the EC firmware are software modules and, if necessary, may be constituted only by the system controller 30.

 In addition, an input / output control hub 40 for determining a voltage level of the charging voltage control signal according to the charging voltage control command and applying it to the charging unit 50 to be described later is provided. That is, the input / output control hub 40 applies a charging voltage control signal of 'low' or 'high' level to the charging unit 50 according to the charging voltage control command for the charging voltage. In FIG. 1, although the input / output control hub 40 is indicated, a south bridge may be used, and if necessary, the input / output control hub 40 may be removed, and the charging voltage control command may be directly applied to the charging unit 50. Note that it can also be configured.

The charging unit 50 is connected to the charging circuit 52 through an external power adapter (not shown) according to the charging circuit 52 charging the battery 10 and the voltage level of the charging voltage control signal. A voltage conversion unit 54 for selectively converting the supplied power supply VCC to a level of the charging voltage (for example, 12.6V or 13.05V) is provided. The voltage converter 54 includes a first resistor R1 and a second resistor R2 connected in series between the power adapter and the ground potential line GND. The third resistor R3 is connected in parallel with the second resistor R2 between the node N between the first resistor R1 and the second resistor R2 and the ground potential line GND. And an N-type Morse (Metal Oxide Semiconductor) -Field Effect Transistor (hereinafter referred to as FET) 56 which is turned on / off in response to the charge voltage control signal. . In addition, a cathode is connected to the drain terminal D of the FET 56, and a reverse voltage prevention diode D1 having an anode connected to the source terminal S is provided. In addition, a general purpose input / output pin (hereinafter referred to as GPIO) for transmitting and receiving the charge voltage control signal to the input / output control hub 40 and the gate terminal D of the FET 56 ( Each of the plurality of GPIOs is preferably provided, and the GPIOs are connected to each other by a data bus to enable transmission and reception of the charging voltage control signal.

Therefore, when the charging voltage control signal is at the 'low' level, the voltage level of the supply power supplied from the voltage converter 54 to the charging circuit 52 is turned off by the FET. Calculated from Equation 1.

[Equation 1]

In other words, the voltage level of the power supplied to the charging circuit 52 is a voltage level distributed by the first resistor R1 and the second resistor R2.

On the other hand, as the charge voltage control signal is applied to the gate terminal G at the 'high' level, the FET 56 forms a current path between the drain terminal D and the source terminal S. FIG. Accordingly, as the FET 56 is turned on by the 'high' level charging voltage control signal, the voltage level of the power supplied from the voltage converter 54 to the charging circuit 52 is represented by the following equation. Calculated from Equation 2.

[Equation 2]

In other words, the voltage level of the power supplied to the charging circuit 52 is divided by the combined resistance of the first resistor R1 and the second resistor R2 and the third resistor R3 connected in parallel. Level.

The first to third resistors R1, R2, and R3 to supply power supplied to the charging circuit 52 at a level of the charging voltage (eg, 12.6 V or 13.05 V) according to Equations 1 and 2 above. ) Is determined.

Next, a battery charging method according to a preferred embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2.

2 illustrates a method of charging a battery having a different charging voltage according to a preferred embodiment of the present invention.

In this case, the power supply is supplied through the power adapter according to the user's power button to start driving the portable device, or when the power adapter is connected and the supply power is supplied while driving the portable device using the battery power. Let's explain.

In the tenth step S10 of FIG. 2, the embedded controller 20 performs communication with the battery 10 to receive battery information, and transmits the battery information to the system controller 30. In this case, the battery information includes a charging voltage, a charging current, a capacity information of the battery, a charging method, an assembly date, a voltage, a current, and an available capacity charged in the battery cell.

In the eleventh step S11, the system controller 30 checks whether the charging voltage is 4.2V among the battery information. As a result of the test, if the charging voltage is 4.2V, the system controller 30 transmits a charging voltage control command for the 4.2V charging voltage to the input / output control hub 40 in the form of an interrupt (S12). Accordingly, the input / output control hub 40 applies a 'low' level charging voltage control signal to the gate terminal G of the FET 56 through the GPIO (S13).

In a fourteenth step S14, the voltage converter 54 supplies the power supply calculated by Equation 1 as the FET 56 maintains a turn-off state according to the 'low' level charge voltage control signal. Is supplied to the charging circuit 52. Accordingly, the charging circuit 52 charges the supplied supply power to the battery 10 (S15). In this case, the supply power, for example, when the six battery cells are connected in series and in parallel by three, the charging voltage is 12.6V.

On the other hand, in the eleventh step (S11), when the charge voltage of the battery 10 is 4.35V, the system controller 30 generates a charge voltage control command for the 4.35V charge voltage (S16). . Subsequently, the input / output control hub 40 transmits a charge voltage control signal having a 'high' level to the FET 56 (S17). As a result, the voltage converter 54 supplies the power supply calculated by Equation 2 to the charging circuit 52 as a current path is formed through the drain terminal D and the source terminal S of the FET 56. Supply (S18). Accordingly, the charging circuit 52 supplies the calculated power supply to charge the battery (S19). In this case, the supply power, for example, when the battery is connected to each of the six battery cells in series and in parallel, the charging voltage is 13.05V.

In the twentieth step S20, when the charging of the battery 10 is terminated, the embedded controller 20 checks whether a new battery is connected. Alternatively, when two or more batteries are mounted at the same time, the next battery to be charged may be detected according to the battery charging sequence.

As a result of the inspection, when the battery to be charged is connected, the eleventh step S11 to the twentieth step S20 are repeatedly performed. If no new battery is required to be charged, the charging operation is terminated.

Through the above process, the present invention selectively converts the supply power from the power adapter according to the charging voltage of the battery according to the charging voltage to charge. Therefore, a battery having different charging voltages is used in one system.

Although the embodiment has been described as controlling the field effect transistor using a charge voltage control command and a control signal, the present invention can be variously changed using a switch for opening and closing a current path and a control module for controlling the field effect transistor. shall. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

As described above, the present invention selectively converts the voltage level of the power supply according to the charging voltage, and charges the battery with the converted supply voltage. Accordingly, the present invention can use a battery having a different charging voltage in one system. As such, the present invention has the advantage of extending the battery coverage by using batteries having different charging voltages.

Claims (10)

A plurality of batteries having different charging voltages, A voltage conversion unit for selectively generating a supply power for the charging voltage of each battery; And a charging circuit for charging the battery by the generated supply power. A plurality of batteries having different charging voltages, An embedded controller communicating with each of the batteries to receive the charging voltage of the battery; A system controller for generating a charge voltage control command for the charge voltage; An input / output control hub configured to determine and output a voltage level of a charge voltage control signal according to the charge voltage control command; And a charging unit for charging the battery by selectively converting the supply power to the voltage level of the charging voltage according to the voltage level of the charging voltage control signal. The method of claim 2, wherein the charging unit, A voltage converter for selectively converting a voltage level of a supply power supplied to the battery according to the voltage level of the charge voltage control signal; And a charging circuit for charging the battery by using the power supply converted from the voltage converter. The method of claim 1 or 3, wherein the voltage conversion unit, First and second resistors configured in series between the supply power supply and the ground potential line to divide the supply power; And a third resistor and a switch connected in parallel with the second resistor. The method of claim 4, wherein the switch, And a field effect transistor for opening and closing according to the voltage level of the charging voltage control signal. The method of claim 5, wherein the field effect transistor, And is driven on when the voltage level of the charging voltage control signal is 'high' level and off when the voltage level of the charging voltage control signal is 'low' level. The method of claim 1 or 2, wherein the charging voltage is, Battery charger characterized in that the 4.2V or 4.35V. Receiving charging voltages of a plurality of batteries having different charging voltages; Generating supply power for charging the battery according to the received charging voltage; And charging the battery using the generated power supply. The method of claim 8, Generating a control command for the charging voltage; And determining a voltage level of a charge voltage control signal according to the control command. The method of claim 8 or 9, wherein the power supply, And a voltage level distributed through different current paths formed by the switches turned on / off by the charging voltage control signal.

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