KR20070029883A - Display device of battery charging state by sense resistor and method - Google Patents

Abstract

A display device of a battery charging state using sense resistor is provided to indicate the charged state of battery such that a user can check the progress in charge at a glance easily. The display device of a battery charging state includes a sense resistor(R) for sensing a current flowing therethrough when a DC voltage is input; a charging part(120) for converting an input current(Iin) and an input voltage(Vin) into a charge current(Iout) and a charge voltage(Vout) to be output; a battery(130) for charging the charge current(Iout) and the charge voltage(Vout); a main control part(140) for calculating the charge current(Iout), determining a charging state therefrom and outputting a control signal indicating the charging state; and a display part(150) for displaying the charging state by the control signal.

Description

Display Device of Battery Charging State by Sense Resistor and Method

1 is a schematic configuration diagram of a conventional charging circuit,

2 is a graph showing a general state of charge,

3 is a configuration diagram of a battery charge state display device according to an embodiment of the present invention;

4 is a graph illustrating a charge progress calculation rate of the battery charge state display device shown in FIG. 3;

5 is an exemplary view illustrating a charging progress rate in the display unit illustrated in FIG. 3;

6 is a flowchart illustrating a method of displaying a state of charge of a battery according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: adapter 110: switching unit

120: charging unit 130: battery

140: main controller 150: display unit

R1: sensitivity resistance R2,... R7: resistance

The present invention relates to an apparatus and method for displaying a battery charge state using a sensitivity resistor, and more particularly, to an apparatus and method for sensing a charging current flowing through a sensitivity resistor and displaying a state of charge of a battery.

In general, portable electronic products receive power from a battery for operation, and the battery converts chemical energy of an internal active material into electrical energy by an electrochemical reaction.

The portable electronic product requires a battery, and since the battery has a limited use time, it causes many restrictions on the use of the portable electronic product.

The battery is divided into a primary battery that is disposed of in a single use and a secondary battery that can be repeatedly recharged, and the secondary battery is a mobile phone, a personal mobile communication device, a common frequency communication device, a wireless data transceiver, a position measuring system. It is used as an important power source for wireless communication devices, laptops and camcorders.

The portable electronic products require the weight reduction of the secondary battery and continuous use for a long time, and recently, lithium-ion (Li-ion) batteries having excellent characteristics in energy density, cycle life, and other performances are commonly used.

1 is a configuration diagram schematically showing the charging circuit of the conventional secondary battery.

As shown in FIG. 1, the secondary battery charging circuit includes an adapter 1, a charging unit 2, and a battery 3.

 When a + 5V voltage is input from the adapter 1 to the charging unit 2, the charging unit 2 outputs a voltage and a current to supply the battery 3.

At this time, the output voltage becomes the charging voltage Vout of the battery 3, and the output current becomes the charging current Iout of the battery 3 to start charging the battery 3.

The characteristics representing the charging voltage Vout and the charging current Iout cross each other as shown in the charging graph of FIG. 2.

Referring to the charging graph of FIG. 2 as an example, before charging, the charging voltage Vout, that is, the voltage of the battery 3 is maintained at 1.8 V, and the charging voltage Vout gradually increases as charging starts.

At this time, the charging current Iout is constantly supplied to the battery 3 at 770 mA, and the charging current Iout is continuously maintained until the battery 3 voltage reaches 4.1 V, and the charging mode in the above state Is called constant current mode.

 Once the voltage of the battery 3 reaches 4.1V, the charging current Iout gradually decreases while the charging voltage Vout continues to be 4.1V, and the charging mode is called a constant voltage mode. .

When the charging current Iout decreases and decreases to 10% (77 mA) of the initial charging current (770 mA), the charging is completed and the charging is stopped.

The above description has been made with respect to the case where the charging current Iout is 770 mA and the fully charged voltage is 4.1 V, but may vary depending on how to set the charging current and the fully charged voltage.

When the portable electronic device is connected to the charging circuit and charged, for example, when the adapter 1 is mounted on the mobile communication terminal in the portable electronic device for charging, the display unit of the mobile communication terminal is being charged. Only two charging states are displayed.

Therefore, the user can only check the charging and the completion of the charging and there is a problem that is uncomfortable and frustrating because the current charging progress can not be confirmed.

The present invention has been made to solve the above-mentioned problems, and when the user charges the battery, the charging current flowing through the sensitivity resistor is displayed to indicate how far the charging is progressing, so the charging progress rate can be easily checked at a glance. SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus and method for displaying a battery charge state using a sensitivity resistor.

Battery charging state display device using a sensitivity resistor according to an embodiment of the present invention for achieving the above object is a sensitivity resistor for detecting the current flowing through the DC voltage, the DC voltage input current through the sensitivity resistor And a charging unit converting the charging voltage and the charging current required for charging when the input voltage is input, and outputting the battery by charging the charging voltage and the charging current output from the charging unit, and the voltage difference between the sensitivity resistors. A main control unit calculates a current, determines a charging state based on the charging current, and outputs a charging state display control signal, and a display unit displaying the charging state by the control signal of the main control unit.

According to an apparatus for displaying a state of charge of a battery using a sensitivity resistor according to an embodiment of the present invention, the main controller compares the charging current with a reference current as a reference for overcurrent, and determines that the charging state is normal when the charging current is smaller than the reference current. And it is characterized by calculating the charging progress degree using the charging current.

According to an apparatus for displaying a state of charge of a battery using a sensitivity resistor according to an embodiment of the present invention, the calculation of the charging progress confirms to which point of the charging graph the charging current proceeds to the battery, and the determined point indicates the total charging progress rate. It is characterized by converting into (%).

According to an apparatus for displaying a state of charge of a battery using a sensitivity resistor according to an embodiment of the present invention, when the charge progress rate cannot be converted to the charge current, the charge voltage and the charge voltage are measured to a certain point of the charge graph by measuring the charge voltage. It is characterized in that the progress, and converting the identified point to the total charging progress rate (%).

According to an embodiment of the present disclosure, a battery charge state display apparatus using a sensitivity resistor may be configured to determine an abnormal state of a charge state when the charge current is not smaller than a reference current, and output an error message display control signal to a display unit. do.

According to an apparatus for displaying a state of charge of a battery using a sensitivity resistor according to an embodiment of the present invention, a switching unit connected to a main control unit is further provided at a front end of the sensitivity resistance, and the main control unit switches when the charging state is determined to be an abnormal state. An off control signal is output to the switching unit, and the switching unit is switched off by the control signal to cut off the DC voltage.

According to the battery charge state display apparatus using the sensitivity resistor according to an embodiment of the present invention, the resistance value of the sensitivity resistor is 0.3 kW.

According to an embodiment of the present invention, a battery charge state display apparatus using a sensitivity resistor may further include a switching unit that cuts off a DC voltage by switching off the front end of the sensitivity resistor.

According to an apparatus for displaying a state of charge of a battery using a sensitivity resistor according to an embodiment of the present invention, an adapter for outputting the DC voltage is provided, and a mobile communication terminal is connected to the adapter, so that the display unit provided in the mobile communication terminal is in a state of charge. It is characterized in that is displayed.

In addition, the battery charging state display method using a sensitivity resistor according to an embodiment of the present invention measures the voltage (V1) of the front and rear ends of the sensitivity resistor, and the voltage difference (V1-V2) of the front and rear ends Calculating a charging current of the battery, determining a charging state by comparing the charging current with a reference current, and calculating the progress of charging using the charging current when the charging state is determined to be normal. And displaying the display unit so that the user can check the progress of the charging.

According to the battery charging state display method using the sensitivity resistor according to an embodiment of the present invention, in the step of calculating the charging current, the current flowing through the sensitivity resistor by dividing the voltage difference (V1-V2) by the resistance value of the sensitivity resistor By calculating, the current flowing through the sensitivity resistor is characterized by recognizing the charging current.

According to the method of displaying the state of charge of a battery using a sensitivity resistor according to an embodiment of the present invention, in the step of calculating the progress of the charging, it is determined to which point of the charging graph the charging current progresses, and the identified point It is characterized by converting to the total filling progress rate (%).

According to the method for displaying the state of charge of a battery using a sensitivity resistor according to an embodiment of the present invention, in the step of calculating the progress of charging, the charging voltage of the battery is measured when the progress of charging cannot be calculated by the charging current. Using the charging voltage and the charging current, it is characterized by calculating the progress of charging.

According to the method for displaying a state of charge of a battery using a sensitivity resistor according to an embodiment of the present invention, in the step of calculating the progress of the charging, it is confirmed to which point of the charge voltage and the charge current the charge graph proceeds, and the confirmation This point is characterized in that the conversion to the full charge progress rate (%).

According to the method of displaying a state of charge of a battery using a sensitivity resistor according to an embodiment of the present invention, in the determining of the state of charge, when it is determined that the abnormal state, the switching-off control signal is connected to the switching unit connected to the front end of the sensitivity resistor. Outputting and switching off the switching unit to cut off the voltage input to the sensitivity resistor.

According to the method for displaying a battery charge state using a sensitivity resistor according to an embodiment of the present invention, when it is determined that the charge state is abnormal, the display unit outputs an error message display control signal to the display unit, and the display unit outputs an error message. Characterizing in further performing the step of displaying.

Hereinafter, the configuration and operation of the embodiments of the present invention with reference to the accompanying drawings.

3 is a block diagram of a battery charge state display device according to an embodiment of the present invention.

As shown in FIG. 3, the charging state display device includes an adapter 100, a switching unit 110, a sensitivity resistor R1, a charging unit 120, a battery 130, a main control unit 140, and a display unit 150. It is configured to include.

The adapter 100 converts and outputs a DC voltage when a general commercial AC power is input.

The switching unit 110 connected to the rear end of the adapter 100 is switched off when an overcurrent flows due to a failure of the battery 130 or the charging unit 120 to cut off the DC voltage input from the adapter 100. Protect the circuit.

The sensitivity resistor R1 connected to the rear end of the switching unit 110 is a current sensing resistor, and the resistance value of the sensitivity resistor R1 in the present invention is 0.3 kΩ.

The charging unit 120 is connected to the rear end of the sensitivity resistor (R1) when the DC voltage output from the adapter 100 is input to the input current (Iin) and the input voltage (Vin) through the sensitivity resistor 110 The output voltage is converted into a charging voltage Vout and a charging current Iout necessary for charging the 130.

The battery 130 charges with the charging voltage Vout and the charging current Iout.

The main controller 140 connected to the terminals IO, ADC1, ADC2, and ADC3 at the front and rear ends of the switching unit 110, the sensitivity resistor R1, and the charging unit 120 may include the charging voltage Vout. The charging current (Iout) is calculated to determine which point of the charging graph has been progressed and converted to the total charging progress rate (%) to be displayed on the display unit 150.

At this time, the main controller 140 detects the voltages V1 and V2 at the front and rear ends of the sensitivity resistor R1 through the terminals ADC1 and ADC2 connected to the front and rear ends of the sensitivity resistor R1 and converts them into digital values. After that, the input current Iin is calculated in the charging unit 120.

The input current Iin is almost equal to the charging current Iout so that the input current Iin becomes the charging current Iout.

If the charging current Iout is greater than the reference current that is the reference of the overcurrent, it is determined to be abnormal, and outputs a high signal to the switching unit 110 through the terminal IO. The switching is turned off by the high signal to cut off the input voltage Vin input to the sensitivity resistor R1.

In addition, by outputting a control signal to display an error message on the display unit 150 so that the error message is displayed on the display unit 150.

The main controller 140 detects the charging voltage Vout through the terminal ADC3 connected to the rear end of the charging unit 120 and converts the charging voltage Vout into a digital value.

As shown in FIG. 5, the display unit 150 not only displays the charging progress rate on the battery display screen 151 under the control of the main controller 140, but also displays an error message so that the user can check the charging state.

The display unit 150 may be a display unit provided in a portable electronic product when the adapter 100 is connected to a portable electronic product such as a mobile communication terminal.

Reference numerals R2 to R7 are resistors.

Hereinafter, a specific embodiment will be described in detail with reference to the charging graph of FIG. 4 and the flowchart of FIG. 6.

FIG. 4 is a graph illustrating a charge progress calculation graph of the battery charge state display device shown in FIG. 3, and FIG.

According to the present invention, the main controller 140 acquires the charging current Iout and the charging voltage Vout, and confirms the current state up to which point of the charging graph shown in FIG. 4, and displays the total charging progress rate on the display unit 150. It is expressed as (%).

The charging graph is mounted inside the charging state display device according to the exemplary embodiment of the present invention for each battery, and in actual implementation, the main controller 140 obtains the total charging progress rate (%) by using the charging graph.

First, when power is supplied to the adapter 100 to start charging of the battery 130 (S600), the main controller 140 may adjust the voltage V1 of the front end of the sensitivity resistor R1 and the voltage V2 of the rear end, respectively. It detects through the terminal (ADC1, ADC2) of and converts into digital value.

The input current Iin of the sensitivity resistor R1 is calculated by Equation 1 using the voltages V1 and V2 and the resistance value R of the sensitivity resistor R1.

For example, when V1 = 5.0V and V2 = 4.77V, and the resistance value R of the sensitivity resistor is 0.3 kΩ, the input current Iin of the sensitivity resistor R1 is about 770 mA by Equation (1). .

Here, since the input current Iin and the charging current Iout of the sensitivity resistor R1 are almost the same, the value calculated by Equation 1, that is, 770 mA becomes the charging current Iout (S610).

The main controller 140 determines whether the charging current Iout calculated by Equation 1 is smaller than a current (hereinafter, referred to as reference current) that is a reference for overcurrent (S620).

When the charging current Iout is smaller than the reference current, the charging state is determined to be a normal state, and the main control unit 140 calculates the charging progress degree, in particular, the total charging progress rate (%), using the charging current Iout (S630). .

Referring to the charging graph of FIG. 4 in the above example, since charging time is 0 minutes to 45 minutes, the charging current (Iout) = 770 mA is not known at which position of the charging current charging graph.

At this time, the main controller 140 detects the charging voltage Vout through the terminal ADC3 and converts it to digital to check the position of the charging graph.

For example, in the case of charging voltage (Vout) = 3.6V, the charging graph is located about 20 minutes after charging, so when the time to fully charge is 1 hour 45 minutes, the entire charging progress rate is converted to 19%. .

Next, the display unit 150 displays the charging progress rate 19% by the control signal of the main controller 140 (S640).

If the charging current (Iout) obtained from V1 and V2 in the step of calculating the charging current (Iout) is 300mA, when viewing the charging graph in the step of calculating the charging progress rate (S630) 1 hour has passed since the start of charging Since the position can be confirmed, it is not necessary to detect the charging voltage Vout.

In this case, since the total charging progress rate is 57%, the charging progress rate 57% is displayed on the display unit 150 in the display step S650 (S640).

In operation S620, when the charging current Iout is smaller than the reference current, if the charging current is greater than the reference current, the main controller determines the normal state, and transmits a high signal to the switching unit 110 through the terminal IO. By outputting, the switching unit 100 is switched off.

Therefore, the input voltage Vin input to the sensitivity resistor R1 is cut off to protect the charging state display device.

In addition, when determining that the main controller 140 is in an abnormal state, the main controller 140 outputs a control signal to display the charging error message on the display unit 150, and the display unit 150 displays the error message by the control signal.

As described above, when the user charges the battery, the charging current flowing to the sensitivity resistor is sensed to indicate the progress of the charging, and thus the charging progress rate can be easily checked at a glance and conveniently charged.

When the charging state display device is implemented when the battery of the mobile communication terminal is charged, and the mobile communication terminal is connected to the adapter, the charging progress rate is displayed on the display unit (LCD screen, etc.) provided in the mobile communication terminal.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art will be able to make various modifications and changes without departing from the essential features of the present invention.

The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas falling within the scope of the present invention should be construed as being included in the scope of the present invention.

As described above, according to the present invention, when the battery is normally charged during charging, the charging progress is indicated by the total charging progress rate (%) so that the user can easily check the charging progress at a glance. If an over current flows to prevent the battery from charging properly, an error message may be displayed to confirm that an error has occurred during charging.

In addition, when the battery is not charging normally, the charging state display device may be protected by cutting off the voltage input to the sensitivity resistor.

Claims (16)

A sensitivity resistor which senses a current flowing in itself when a DC voltage is input; A charging unit converting the DC voltage into a charging voltage and a charging current required for charging when the DC voltage is input as an input current and an input voltage through a sensitivity resistor; A battery charged with a charging voltage and a charging current output from the charging unit; A main control unit calculating a charging current using the voltage difference across the sensitivity resistor, and determining a charging state using the charging current and outputting a charging state display control signal; And And a display unit for displaying a state of charge by a control signal of the main controller. The method of claim 1, The main control unit compares the charging current with a reference current that is a reference for overcurrent, and determines that the charging state is normal when the charging current is less than the reference current, and calculates the charging progress using the charging current. Battery status indicator using resistors. The method of claim 2, The charging progress calculation is to determine the point where the charging current has progressed to the charging graph for each battery, and the battery charge status display device using a sensitivity resistor, characterized in that the converted point in terms of the total charging progress rate (%) . The method of claim 3, wherein When the charging progress rate cannot be converted by the charging current, the charging voltage is measured to determine where the charging current and the charging voltage have progressed to the charging graph, and the point is converted into the total charging progress rate (%). Battery charge state display device using a sensitivity resistor, characterized in that. The method of claim 2, And if the charging current is not less than the reference current, determines the charging state as an abnormal state, and outputs an error message display control signal to the display unit. The method of claim 5, A switching part connected to the main control part is further provided in front of the sensitivity resistor, and the main control part outputs a switching off control signal to the switching part when it is determined that the charging state is abnormal. The battery charge state display device using a sensitivity resistor, characterized in that switching off by blocking the DC voltage. The method of claim 1, The battery charge state display device using a sensitivity resistor, characterized in that the resistance value of the sensitivity resistor is 0.3Ω. The method of claim 1, And a switching unit which cuts off the DC voltage by switching off the front end of the sensitivity resistor. The method according to any one of claims 1 to 8, An adapter for outputting the DC voltage is provided, the mobile communication terminal is connected to the adapter, the state of charge of the battery using the sensitivity resistor, characterized in that the charging state is displayed on the display unit provided in the mobile communication terminal. Measuring a voltage V1 at the front end of the sensitivity resistor and a voltage V2 at the rear end, and calculating a charging current of the battery using the voltage difference V1 -V2 at the front end and the rear end; Determining the state of charge by comparing the charge current with a reference current; Calculating a progress of charging by using a charging current when the charging state is determined to be a normal state; And And displaying a display on the display unit so that the user can check the progress of the charging. The method of claim 10, In the step of calculating the charging current, by dividing the voltage difference (V1-V2) by the resistance value of the sensitivity resistor to calculate the current flowing through the sensitivity resistor, it characterized in that the current flowing through the sensitivity resistor as a charging current How to display battery charge state using sensitivity resistor. The method of claim 10, In the step of calculating the progress of the charging, it is confirmed to which point of the charging current the charging current progressed, the battery charging using the sensitivity resistor, characterized in that converted into the total charging progress rate (%) How to show status. The method of claim 10, In the step of calculating the progress of the charging, when the progress of the charge can not be calculated by the charging current, measuring the charging voltage of the battery, characterized in that for calculating the progress of the charging using the charging voltage and the charging current How to display the state of charge of the battery using a sensitivity resistor. The method of claim 13, In the step of calculating the progress of the charging, to determine the point where the charging voltage and the charging current has proceeded to the charging graph, the sensitivity resistor, characterized in that converted into the total charging progress rate (%) How to display the battery charge state using. The method of claim 10, In the determining of the state of charge, when it is determined that the abnormal state, the step of outputting a switching-off control signal to the switching unit connected to the front end of the sensitivity resistor, the switching unit is switched off to cut off the voltage input to the sensitivity resistor Battery charging status display method using a sensitivity resistor, characterized in that further performing. The method according to claim 10 or 15, When it is determined that the charging state is abnormal, the battery charging state using the sensitivity resistor may further include outputting an error message display control signal to the display unit and displaying the error message on the display unit. How to display.

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