KR101295182B1 - Test apparatus of battery protection circuit and method for testing passive elements thereof - Google Patents

Abstract

PURPOSE: A test apparatus of a battery protection circuit and a passive element measuring method thereof are provided to reduce manufacturing costs while improving productivity. CONSTITUTION: A test apparatus (100) of a battery protection circuit comprises first and second terminals, and passive element test circuit. The passive element test circuit is connected with a battery protection circuit through first and second application terminals and tests passive elements. The passive element test circuit comprises: a first switch connected between a first cell terminal and a ground terminal; a first power source terminal which applies first voltage; a second switch connected between second cell terminals; and a first standard resistor connected between the second switch and the second cell terminal. The passive element test circuit applies the first voltage to the first power source terminal. The passive element test circuit measures voltage of the second cell terminal by turning on the first switch and the second switch at the same time and calculates first resistor. [Reference numerals] (10) Battery cells; (100) Test apparatus; (110) Passive device test circuit; (2) Battery pack; (200) Battery protection circuit

Description

TEST APPARATUS OF BATTERY PROTECTION CIRCUIT AND METHOD FOR TESTING PASSIVE ELEMENTS THEREOF}

The present invention relates to a test device for a battery protection circuit, and more particularly, to eliminate a cause of an increase in the manufacturing cost of a battery pack and to improve productivity, a test device for a battery protection circuit and a passive element measurement provided in the battery protection circuit thereof. It is about a method.

In general, portable electronic devices such as mobile phones, digital cameras, smartphones, and tablet PCs have battery packs for power supply. The battery pack generates heat during overcharging and overcurrent, and if the heating continues to increase the temperature, there is a high risk of fire and explosion as well as performance deterioration. Accordingly, battery packs are generally equipped with a battery protection circuit for sensing and blocking overcharge, overdischarge, and overcurrent.

The battery protection circuit may block overcharge, overdischarge, overcurrent, short circuit, and reverse voltage of the battery cells, thereby preventing the battery pack from being exploded, overheated, leaked, or deteriorated in charge and discharge.

The battery protection circuit generally includes a protection IC on the printed circuit board, and a plurality of passive elements such as two switching circuits (FETs), resistors and capacitors. The battery protection circuit is usually mounted in a battery pack in the form of a module. Therefore, the battery protection circuit is provided in the form of being disposed in one housing together with the at least one battery cells in a subsequent packaging process to configure one battery pack.

When an abnormal condition such as overcharge, overdischarge, or overcurrent occurs, the protection IC controls the switching circuits to block charging or discharging of the battery cells.

This battery protection circuit uses a test facility to test the protection IC and two switching circuits (FETs) to determine normal in-phase conditions. However, at present, a test of a plurality of passive devices provided in the battery protection circuit using a test facility has not been performed. For example, the test facility cannot directly contact both ends of each of the passive elements to measure resistance or capacitance. Therefore, the battery pack is packaged by a subsequent packaging process without testing of passive components.

As a result, when an abnormality occurs in a plurality of passive elements included in the battery protection circuit, the battery pack must be treated as defective in a packaged state, thereby lowering productivity, thereby causing a rise in manufacturing cost.

Even in the case of testing passive components, even if a short defect occurs in the resistance component of the passive components, or in the case of an open defect in the case of a capacitor component, it can be treated as a good product. In order to measure the heavy capacitor component, there is a problem in that the capacitance cannot be measured due to parasitic diodes and leakage currents inside the protection IC when the AC power is applied to the battery protection circuit.

It is an object of the present invention to provide a test apparatus and method for determining the presence or absence of abnormalities for a plurality of passive elements provided in a modular battery protection circuit prior to packaging of a battery pack.

Another object of the present invention is to provide a test apparatus for a battery protection circuit and a passive element measuring method thereof for removing the cause of the increase in manufacturing cost of the battery pack.

It is still another object of the present invention to provide a test apparatus for a battery protection circuit and a passive element measuring method thereof for improving the productivity of the battery pack.

In order to achieve the above objects, a test apparatus of a battery protection circuit is characterized by testing a plurality of passive elements provided in the battery protection circuit. Such a test device can test passive components before the battery protection circuit is packaged into a battery pack, providing productivity and manufacturing cost savings.

According to an aspect of the present invention, a test apparatus for a battery protection circuit includes a switching circuit having a protection integrated circuit, first and second switching elements connected to the protection integrated circuit, and a plurality of passive elements. The passive elements of the battery protection circuit including the first and second cell terminals connected to one battery cell and the first and second application terminals connected to the application are tested.

The passive elements are disposed between a first resistor disposed between the first cell terminal and a voltage applying terminal of the protection integrated circuit, and between the voltage applying terminal and a voltage reference terminal of the protection integrated circuit, thereby providing the first resistor R1. A first capacitor connected in series with each other); The test apparatus includes a passive element test circuit connected to the battery protection circuit through the first and second cell terminals and the first and second application terminals to test the passive elements; The passive device test circuit may include a first switch connected between the first cell terminal and ground, a second switch connected between a first power supply terminal applying a first voltage and the second cell terminal, and the second switch. And a first reference resistor connected between the second cell terminal and the second cell terminal to apply the first voltage to the first power supply terminal and simultaneously turn on the first and second switches, thereby providing the second cell terminal. The first resistance is calculated by measuring the voltage of.

The passive elements may further include a second resistor connected between the voltage sensing terminal of the protection integrated circuit and the second application terminal to which the source terminal of the second switching element is connected; The passive element test circuit may include a second reference resistor connected to the first cell terminal and disposed in series between the second application terminal and a second power supply terminal for applying a second voltage; And further including a third switch, applying the second voltage to the second power supply terminal, and simultaneously turning on the first and the third switches to measure the voltage of the second application terminal so as to measure the second resistance. To calculate.

In another example embodiment, the passive device test circuit may include a fourth switch connected between a third power supply terminal for applying a third voltage and the first cell terminal, and a fourth switch connected between the fourth switch and the first cell terminal. A first voltage follower connected between a third reference resistor, the third reference resistor, and the first cell terminal, and an output terminal connected to the second application terminal; And a fifth switch connected between an output terminal and the second application terminal, and a sixth switch connected between the second cell terminal and ground, and simultaneously applying the third voltage to the third power supply terminal. The fourth to sixth switches are turned on, and after a predetermined time elapses, the voltage of the first cell terminal is measured to calculate the first capacitor.

In another embodiment, the passive elements may include a second capacitor connected between the first and second application terminals, and the second cell to which the second application terminal and a source terminal of the first switching device are connected. A third capacitor coupled between the terminals; The passive device test circuit may include a fourth reference resistor connected between the sixth switch and the second cell terminal, the fourth power supply terminal applying a fourth voltage and the second application terminal, and the non-inverting input terminal being connected to the second application terminal. A second voltage follower connected between a second application terminal and the fourth reference resistor, an output terminal connected between the first cell terminal, and a connection between the first cell terminal and an output terminal of the second voltage follower And a seventh switch and an eighth switch connected between the fourth reference resistor and the second application terminal to apply the fourth voltage to the fourth power supply terminal, and simultaneously 8 After the switch is turned on and the predetermined time has passed, the voltage of the second application terminal is measured to calculate the second capacitor.

In another exemplary embodiment, the passive device test circuit may include a ninth switch connected to a fifth power supply terminal applying a fifth voltage, a fifth reference resistor connected between the ninth switch and the first cell terminal; A third voltage follower connected between a non-inverting input terminal between the first cell terminal and the fifth reference resistor, and an output terminal connected to an inverting input terminal and the second cell terminal; and an inverting input terminal of the third voltage follower. And a tenth switch connected between the second cell terminal and the second cell terminal, and an eleventh switch connected between the second application terminal and the ground, applying the fifth voltage to the fifth power supply terminal, and simultaneously After the ninth to eleventh switches are turned on, after a predetermined time, the voltage of the first cell terminal is measured to calculate the third capacitor.

In another embodiment, the passive device test circuit tests each of the passive devices without a switching operation in response to threshold voltages of the first and second switching devices.

In another embodiment, the passive device test circuit; When the capacities of the first to third voltage followers are the same, the predetermined time is set to be the same.

According to another feature of the invention, a passive element test method is provided for testing the passive elements of the battery protection circuit using the test apparatus as claimed in claim 5.

The passive element test method according to this aspect uses a first drop voltage generated across the first parasitic diode generated between the voltage applying terminal and the voltage reference terminal of the protection integrated circuit, and the first reference resistor. To test the first resistance. The second drop voltage generated at both ends of the second parasitic diode generated between the voltage applying terminal and the voltage sensing terminal of the protection integrated circuit, the second reference resistance and the measured first resistor. 2 Test the resistance. The first voltage follower is used to disable the second and third capacitors, and the third capacitor is tested using the third reference resistance and the measured first resistor. The second voltage follower is used to disable the first and the third capacitors, and the second capacitor is tested using the fourth reference resistor. The third and second capacitors are then used to disable the first and second capacitors, and the third capacitor is tested using the fifth reference resistor.

In one embodiment, the method further comprises: The battery protection circuit is processed before the protection integrated circuit, the switching circuit and the passive components are modularized and packaged into a battery pack.

As described above, the test apparatus of the battery protection circuit according to the present invention, by testing a plurality of passive elements provided in the battery protection circuit before the battery protection circuit is packaged in the battery pack, thereby improving productivity and reducing manufacturing costs. Can be.

In addition, the test apparatus of the battery protection circuit according to the present invention provides a method for testing a plurality of passive elements provided in the battery protection circuit, it is possible to easily test the battery protection circuit in the production line.

In addition, the test apparatus of the battery protection circuit according to the present invention can improve the quality and reliability of the battery protection circuit by testing a plurality of passive elements included in the battery protection circuit.

1 is a block diagram showing a connection configuration of a test apparatus for measuring the presence or absence of abnormalities for passive elements of a battery protection circuit according to the present invention;
2 is a circuit diagram illustrating a configuration according to an embodiment of the battery protection circuit shown in FIG. 1;
3 is a circuit diagram showing a partial configuration of a test apparatus for testing the first resistance shown in FIG.
4 is a circuit diagram showing a partial configuration of a test apparatus for testing the second resistance shown in FIG.
FIG. 5 is a circuit diagram showing a partial configuration of a test apparatus for testing the first capacitor shown in FIG. 2;
FIG. 6 is a waveform diagram showing a relationship between the third voltage and the first cell terminal voltage shown in FIG. 5; FIG.
FIG. 7 is a circuit diagram showing some components of a test apparatus for testing the second capacitor shown in FIG. 2; FIG.
FIG. 8 is a waveform diagram illustrating a relationship between the fourth voltage and the second application terminal voltage shown in FIG. 7;
FIG. 9 is a circuit diagram showing some components of a test apparatus for testing the third capacitor shown in FIG. 2; FIG.
10 is a waveform diagram showing a relationship between the fifth voltage and the first cell terminal voltage shown in FIG. 9; And
11 is a flowchart illustrating a processing procedure for testing the presence or absence of abnormalities for a plurality of passive elements using the test apparatus of the battery protection circuit according to the present invention.

The embodiments of the present invention can be modified into various forms and the scope of the present invention should not be interpreted as being limited by the embodiments described below. The present embodiments are provided to enable those skilled in the art to more fully understand the present invention. Therefore, the shapes and the like of the components in the drawings are exaggerated in order to emphasize a clearer explanation.

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

1 is a block diagram showing a connection configuration of a test apparatus for measuring the presence or absence of abnormality for the passive elements of the battery protection circuit according to the present invention.

Referring to FIG. 1, the test apparatus 100 of the present invention includes a passive device test circuit therein for determining whether a plurality of passive devices, such as a resistor and a capacitor, are provided in the battery protection circuit 200. 110 to test each passive element. To this end, the test apparatus 100 may pass passive components of the modular battery protection circuit 200 before the battery protection circuit 200 is packaged with the at least one battery cell 10 to configure the battery pack 2. Test it.

That is, the test apparatus 100 includes the passive device test circuit 110 illustrated in FIGS. 3 to 9. The passive device test circuit 110 is connected to the battery protection circuit 200 through a plurality of terminals (CP, CN, PP, PN in FIG. 2) so that it can be applied in a production line.

Therefore, the test apparatus 100 of the present invention easily measures the resistance value and the capacitance of each of the passive elements of the battery protection circuit 200 using the passive element test circuit 110. In addition, the test apparatus 100 may test the protection IC and the switching circuits of the battery protection circuit 200.

Specifically, a configuration of a test apparatus for testing a battery protection circuit will be described in detail with reference to FIGS. 2 to 10.

First, FIG. 2 is a circuit diagram illustrating a configuration according to an embodiment of the battery protection circuit shown in FIG. 1.

Referring to FIG. 2, the battery protection circuit 200 of this embodiment includes a protection IC 210, a switching circuit 220, and a plurality of passive elements R1, R2, C1, C2, and C3.

The battery protection circuit 200 may be connected to cell terminals CP and CN connected to at least one battery cell 10 and to an application (not shown), for example, a battery charging device or a portable electronic device. Application terminals PP, PN.

The protection IC 210 blocks the charging or discharging of the battery cells 10 by controlling the switching circuit 220 when an abnormal situation such as overcharge, overdischarge, or overcurrent occurs. The switching circuit 220 includes, for example, two switching elements FETs in the form of one integrated circuit IC, and includes first and second switching elements FET1 and FET2 having a drain common structure. .

The protection IC 210 is connected to the first cell terminal CP through the first resistor R1, and is a voltage to which a charge voltage or a discharge voltage is applied from the battery cells 10 through the first cell terminal CP. The application terminal Vdd, the voltage reference terminal Vss serving as a reference for the operating voltage inside the protection IC 210, the voltage sensing terminal V- for detecting the charge / discharge state, A first output terminal DO for outputting a discharge blocking signal for turning off the first switching element FET1 and a second output terminal for outputting a charge blocking signal for turning off the second switching element FET2 in an overcharge state ( C0).

In this case, although not shown in the drawing, the protection IC 210 includes a reference voltage setting unit, a comparison unit for comparing the reference voltage and the charge / discharge voltage, an overcurrent detector, a charge / discharge detector, and the like. Here, the criterion for determining the charge and discharge states may be changed to a specification required by the user, and the charge and discharge states are determined by recognizing a voltage difference for each terminal of the protection IC 210 according to the determined criterion.

When the protection IC 210 is in an over-discharge state during discharge, the protection IC 210 outputs a low level signal to the first output terminal DO to turn off the first switching device FET1. In addition, the protection IC 210 turns off the second switching element FET2 by outputting a low level signal to the second output terminal CO when the overcharge state is at the time of charging. When overcurrent is detected, the protection IC 210 turns off the first switching element FET1 during discharge and turns off the second switching element FET2 during charging.

In this embodiment, the passive elements include first and second resistors R1 and R2 and first to third capacitors C1, C2 and C3.

Among the passive elements, the first resistor R1 and the first capacitor C1 serve to stabilize fluctuations in the power supply of the protection IC 210. That is, the first resistor R1 is disposed between the first cell terminal CP connected to the battery cells 10 and the voltage application terminal Vdd of the protection IC 210, and the first capacitor C1 is protected. It is disposed between the voltage application terminal (Vdd) and the voltage reference terminal (Vss) of the IC (210), it is connected in series with the first resistor (R1).

At this time, the first parasitic diode D1 is generated between the voltage applying terminal Vdd and the voltage reference terminal Vss in the protection IC 210, and the voltage applying terminal Vdd and the voltage sensing terminal V− are generated. The second parasitic diode (D2) is generated between.

The second resistor R2 is disposed between the voltage sensing terminal V− of the protection IC 210 and the second application terminal PN to which the source terminal of the second switching element FET2 is connected.

The second capacitor C2 is connected between the first and second application terminals PP and PN, and the third capacitor C3 is a source terminal of the second application terminal PN and the first switching element FET1. Is connected between the connected second cell terminals CN. The second and third capacitors C2 and C3 stabilize the battery protection circuit 200 by improving resistance to voltage fluctuations or external noise.

The battery protection circuit 200 mounts the protection IC 210, the switching circuit 220, and the passive devices R1, R2, C1, C2, and C3 on a single printed circuit board to be modularized. The modular battery protection circuit 200 is packaged inside at least one battery cell 10 and one housing when packaging in a subsequent packaging process to form the battery pack 2.

Therefore, the test apparatus 100 according to the present invention uses the passive element test circuit 110 to check whether the passive elements R1, R2, C1, C2, and C3 are abnormal before the modular battery protection circuit 200 is packaged. It can be easily tested.

3 to 10 are circuit diagrams each showing some components of a test apparatus for testing each of the plurality of passive elements shown in FIG. 2 and waveform diagrams for internal reference voltages for testing each passive element.

That is, FIG. 3 is a circuit diagram illustrating the configuration of some passive element test circuits and a battery protection circuit of the test apparatus for testing the first resistance shown in FIG. 2.

Referring to FIG. 3, the passive device test circuit 110 includes first and second switches SW1 and SW2 and a first reference resistor Rr1.

The first switch SW1 is connected between the first cell terminal CP and the ground. The second switch SW2 is connected between the first power supply terminal applying the first voltage Vr1 and the second cell terminal CN. The first reference resistor Rr1 is disposed between the second switch SW2 and the second cell terminal CN.

Therefore, in this embodiment, the passive element test circuit 110 applies the first voltage Vr1 to the first power supply terminal and simultaneously turns on the first and second switches SW1 and SW2, thereby providing the voltage of the second cell terminal. Measure (Vcn). At this time, if the current applied to the first reference resistor Rr1 is I1 and the voltage of the second cell terminal CN is Vcn, the current I1 and the first resistor R1 are calculated as in Equation 1 below. .

[Equation 1]

I1 = (Vr1-Vcn) / Rr1

R1 = (Vcn-Vf1) / I1

   = Rr1 (Vcn-Vf1) / (Vr1-Vcn)

Here, the voltage Vf1 is a first drop voltage generated at both ends of the first parasitic diode D1 generated between the voltage applying terminal Vdd and the voltage reference terminal Vss in the protection IC 210. to be.

At this time, the test apparatus 100 of the present invention corresponds to the passive elements R1, R2, and C1 in response to the threshold voltage Vth of the first and second switching elements FET1 and FET2 without the switching operation of the switching circuit 210. , C2, C3) can each be tested.

Therefore, the passive device test circuit 110 according to the present invention uses the first drop voltage Vf1 generated at both ends of the first parasitic diode D1 of the protection IC 210 and the first reference resistor Rr1. Calculate the resistance R1. As a result, it may be determined whether the first resistor R1 is abnormal based on the measured resistance value.

FIG. 4 is a circuit diagram illustrating a configuration of some passive element test circuits and a battery protection circuit of the test apparatus for testing the second resistor illustrated in FIG. 2.

Referring to FIG. 4, the passive device test circuit 110 further includes a third switch SW3 and a second reference resistor Rr2.

The passive device test circuit 110 connects the first switch SW1 to the first cell terminal CP, and between the second application terminal PN and a second power supply terminal applying the second voltage Vr2. The second reference resistor Rr2 and the third switch SW3 are connected in series with each other.

Therefore, the passive element test circuit 110 applies the second voltage Vr2 to the second power supply terminal, and simultaneously turns on the first and third switches SW1 and SW3 to provide the voltage of the second application terminal PN. Vpn) is measured. At this time, if the current applied to the second reference resistor Rr2 is I2 and the voltage of the second application terminal PN is Vpn, the currents I2 and the second resistor R2 are calculated as shown in Equation 2 below. do.

&Quot; (2) "

I2 = (Vr2-Vpn) / Rr2

R2 = (Vpn-Vf2) / I2-R1

   = Rr2 (Vpn-Vf2) / (Vr2-Vpn)-R1

Here, the voltage Vf2 is a second drop voltage generated at both ends of the second parasitic diode D2 generated between the voltage applying terminal Vdd and the voltage sensing terminal V− in the protection IC 210.

Therefore, the passive device test circuit 110 is measured by the second drop voltage Vf2 generated across the second parasitic diode D2 of the protection IC 200, the second reference resistor Rr2, and FIG. 3. The second resistor R2 is calculated using the first resistor R1.

FIG. 5 is a circuit diagram illustrating a configuration of some passive device test circuits and a battery protection circuit of a test apparatus for testing the first capacitor illustrated in FIG. 2, and FIG. 6 is a diagram illustrating a third voltage and a first cell illustrated in FIG. 5. This is a waveform diagram showing the relationship between terminal voltages.

Referring to FIG. 5, the passive device test circuit 110 may include the fourth to sixth switches SW4, SW5, and SW6, a first voltage follower U1, and a third reference resistor Rc1. It includes more.

The fourth switch SW4 is disposed between the third power supply terminal applying the third voltage Vc1 and the first cell terminal CP, and the third reference resistor Rc1 is the fourth switch SW4 and the first cell. It is arranged between the terminals CP. For example, the first voltage follower U1 is provided as a non-inverting amplifier, and a non-inverting input terminal is connected between the third reference resistor Rc1 and the first cell terminal CP, and the output terminal is the second application terminal PN. ) The fifth switch SW5 is disposed between the output terminal of the first voltage follower U1 and the second application terminal PN. The sixth switch SW6 is connected between the second cell terminal CN and the ground.

Therefore, the passive device test circuit 110 applies the third voltage Vc1 to the third power supply terminal and simultaneously turns on the third to fifth switches SW3, SW4, and SW5, as shown in FIG. 6. After a predetermined time T, the voltage Vcp of the first cell terminal CP is measured. At this time, when the third voltage Vc1 is applied, the second and third capacitors C2 and C3 are disabled by the first voltage follower U1. The time T is preset according to the device characteristics of the first voltage follower U1. As a result, the first capacitor C1 is calculated as in Equation 3 below.

&Quot; (3) "

Vdd = Vc1 [1-e ^ {(-T) / ((Rc1 + R1) * C1)}]

Vcp = Vc1-(Vc1-Vdd) * {Rc1 / (R1 + Rc1)}

C1 = (-T) / (Rc1 + R1) * ln [1-{(R1 + Rc1) * Vcp-(R1 * Vc1)} / (Rc1 * Vc1)]

Therefore, the passive device test circuit 110 disables the second and third capacitors C2 and C3 using the first voltage follower U1, and the third reference resistor Rc1 and the measured first resistor ( The first capacitor C1 is measured using R1).

FIG. 7 is a circuit diagram illustrating a configuration of some passive device test circuits and a battery protection circuit of a test apparatus for testing the second capacitor illustrated in FIG. 2, and FIG. 8 is a diagram illustrating the fourth voltage and the second application illustrated in FIG. 7. This is a waveform diagram showing the relationship between terminal voltages.

7 and 8, the passive device test circuit 110 further includes seventh and eighth switches SW7 and SW8, a second voltage follower U2, and a fourth reference resistor Rc2. .

The fourth switch SW6 is connected to the second cell terminal CN, and the fourth reference resistor Rc2 and the eighth switch SW8 are connected to the fourth power supply terminal and the second application terminal to apply the fourth voltage Vc2. (PN) are connected in series with each other. In the second voltage follower U2, the non-inverting input terminal is connected between the second application terminal PN and the fourth reference resistor Rc2, and the output terminal is connected between the first cell terminal CP. In addition, the seventh switch SW7 is connected between the first cell terminal CP and the output terminal of the second voltage follower U2.

Therefore, the passive element test circuit 110 applies the fourth voltage Vc2 to the fourth power supply terminal and simultaneously turns on the sixth to eighth switches SW6, SW7, and SW8, and after a predetermined time T1 elapses, The voltage Vpn of the second application terminal PN is measured. At this time, when the fourth voltage Vc2 is applied, the first and third capacitors C1 and C3 are disabled by the second voltage follower U2. The time T1 is preset according to the device characteristics of the second voltage follower U2. As a result, the second capacitor C2 is calculated as shown in Equation 4 below.

&Quot; (4) "

Vpn = Vc2 [1-e ^ {(-T1) / (Rc2 * C2)}]

C2 = (-T1) / {Rc2 * ln (1-Vpn / Vc2)}

Therefore, the passive device test circuit 110 disables the first and third capacitors C1 and C3 using the second voltage follower U2 and uses the second reference resistor Rc2 to perform the second capacitor C2. ), The second capacitor C2 can be tested.

FIG. 9 is a circuit diagram illustrating a configuration of some passive element test circuits and a battery protection circuit of a test apparatus for testing a third capacitor illustrated in FIG. 2, and FIG. 10 is a diagram illustrating a fifth voltage and a first voltage illustrated in FIG. 9. This is a waveform diagram showing the relationship between cell terminal voltages.

9 and 10, the passive device test circuit 110 further includes the ninth through eleventh switches SW9, SW10, and SW11, the third voltage follower U3, and the fifth reference resistor Rc3. Include.

The eleventh switch SW11 is connected between the second application terminal PN and ground, and the ninth switch SW9 and the fifth reference resistor Rc3 are connected to a fifth power supply terminal for applying a fifth voltage Vc3. It is connected in series between one cell terminal CP. In the third voltage follower U3, the non-inverting input terminal is connected between the first cell terminal CP and the fifth reference resistor Rc3, and the output terminal is connected to the inverting input terminal. In addition, the inverting input terminal of the third voltage follower U3 is connected to the second cell terminal CN. The tenth switch SW10 is connected between the inverting input terminal of the third voltage follower U3 and the second cell terminal CN.

Therefore, the passive element test circuit 110 applies the fifth voltage Vc3 to the fifth power supply terminal and simultaneously turns on the ninth to eleventh switches SW9, SW10, and SW11, and after a predetermined time T2, The voltage Vcp of the first cell terminal CP is measured. At this time, when the fifth voltage Vc3 is applied, the first and second capacitors C1 and C2 are disabled by the third voltage follower U3. The time T2 is preset according to the device characteristics of the third voltage follower U3. As a result, the third capacitor C3 is calculated as in Equation 5 below.

&Quot; (5) "

Vcp = Vc3 [1-e ^ {(-T2) / (Rc3 * C3)}]

C3 = (-T2) / {Rc3 * ln (1-Vcp / Vc3}

Therefore, the passive element test circuit 110 disables the first and second capacitors C1 and C2 using the third voltage follower U3 and uses the third reference resistor Rc3 to perform the third capacitor C3. Measure

Here, the predetermined time T, T1, and T2 are set differently depending on the capacitance and device characteristics of the first to third voltage followers U1, U2, and U3, but the first to third voltage followers U1, If U2 and U3 have the same capacitance and device characteristics, these constant times T, T1 and T2 are set identically.

11 is a flowchart illustrating a processing procedure for testing the presence or absence of abnormalities for a plurality of passive elements using the test apparatus of the battery protection circuit according to the present invention.

Referring to FIG. 11, the test apparatus 100 of the present invention tests each of the plurality of passive elements R1, R2, C1, C2, and C3 using the passive element test circuit 110.

That is, in step S300, the passive device test circuit 110 uses the first drop voltage Vf1 generated at both ends of the first parasitic diode D1 of the protection IC 210 and the first reference resistor Rr1. The first resistor R1 is measured. To this end, as shown in FIG. 3, the passive device test circuit 110 applies the first voltage Vr1 to the first power supply terminal, and simultaneously turns on the first and second switches SW1 and SW2. Measure the voltage Vcn of the two-cell terminal CN. Therefore, in Equation 1, since the first voltage Vr1, the first reference resistor Rr1, the first drop voltage Vf1, and the like have constant values, the first resistor R1 may be calculated. 1 Whether the resistance R1 is abnormal can be determined.

In operation S310, the passive device test circuit 110 measures the second drop voltage Vf2 generated across the second parasitic diode D2 of the protection IC 210, the second reference resistance Rr2, and the operation S300. The second resistor R2 is measured using the first resistor R1. As shown in FIG. 4, the passive device test circuit 110 applies the second voltage Vr2 to the second power supply terminal and simultaneously turns on the first and third switches SW1 and SW3 to provide a second application. The voltage Vpn of the terminal PN is measured. Therefore, in Equation 2, since the second voltage Vr2, the first reference resistor Rr2, and the second drop voltage Vf2 have constant values, the second resistor R2 may be calculated.

In operation S320, the passive device test circuit 110 disables the second and third capacitors C2 and C3 by using the first voltage follower U1, and the third reference resistor ( The first capacitor C1 is measured using Rc1) and the first resistor R1 measured in step S300. That is, the passive element test circuit 110 applies the third voltage Vc1 to the third power supply terminal and simultaneously turns on the third to fifth switches SW3, SW4, and SW5, and after a predetermined time T passes. The voltage Vcp of the first cell terminal CP is measured, and the first capacitor C1 is calculated by using Equation 3 below.

In operation S330, the passive device test circuit 110 disables the first and third capacitors C1 and C3 using the second voltage follower U2, and uses the fourth reference resistor Rc2 to disable the second capacitor. (C2) is measured. That is, the passive element test circuit 110 applies the fourth voltage Vc2 to the fourth power supply terminal and simultaneously turns on the sixth to eighth switches SW6, SW7, and SW8, and after a predetermined time T1 has elapsed. The voltage Vpn of the second application terminal PN is measured. At this time, when the fourth voltage Vc2 is applied, the first and third capacitors C1 and C3 are disabled by the second voltage follower U2. As a result, the second capacitor C2 may be calculated using Equation 4.

In operation S340, the passive device test circuit 110 disables the first and second capacitors C1 and C2 using the third voltage follower U3, and uses the third reference resistor Rc3 to perform a third operation. Measure the capacitor (C3). That is, the passive element test circuit 110 applies the fifth voltage Vc3 to the fifth power supply terminal and simultaneously turns on the ninth to eleventh switches SW9, SW10, and SW11 to pass the predetermined time T2. The voltage Vcp of the first cell terminal CP is measured. At this time, when the fifth voltage Vc3 is applied, the first and second capacitors C1 and C2 are disabled by the third voltage follower U3. As a result, the third capacitor C3 is calculated using Equation 5 to determine whether there is an abnormality.

As described above, the test apparatus 100 of the battery protection circuit 200 of the present invention measures a plurality of passive elements R1, R2, C1, C2, and C3, and when an abnormality occurs, the battery protection circuit 200 By detecting before packaging), productivity can be improved, thereby reducing the manufacturing cost of the battery pack 2.

In the above, the configuration and operation of the test apparatus of the battery protection circuit according to the present invention has been shown according to the detailed description and drawings, but this is merely described by way of example, and various changes without departing from the technical spirit of the present invention. And changes are possible.

2: battery pack
10: battery cells
100: test device
110: passive device test circuit
200: battery protection circuit
210: Protection IC
220: switching circuit

Claims (9)

A switching circuit having a protection integrated circuit, first and second switching elements connected to the protection integrated circuit, and first and second cell terminals including a plurality of passive elements and connected to at least one battery cell. And a test apparatus of a battery protection circuit having first and second application terminals connected to an application.
The passive elements are disposed between a first resistor disposed between the first cell terminal and a voltage applying terminal of the protection integrated circuit, and between the voltage applying terminal and a voltage reference terminal of the protection integrated circuit, thereby providing the first resistor R1. A first capacitor connected in series with each other);
The test apparatus includes a passive element test circuit connected to the battery protection circuit through the first and second cell terminals and the first and second application terminals to test the passive elements;
The passive device test circuit may include a first switch connected between the first cell terminal and ground, a second switch connected between a first power supply terminal applying a first voltage and the second cell terminal, and the second switch. And a first reference resistor connected between the second cell terminal and the second cell terminal to apply the first voltage to the first power supply terminal and simultaneously turn on the first and second switches, thereby providing the second cell terminal. The first resistance device is calculated by measuring a voltage of. The method of claim 1,
The passive elements further comprise a second resistor connected between the voltage sensing terminal of the protection integrated circuit and the second application terminal to which the source terminal of the second switching element is connected;
The passive element test circuit may include a second reference resistor connected to the first cell terminal and disposed in series between the second application terminal and a second power supply terminal for applying a second voltage; And further including a third switch, applying the second voltage to the second power supply terminal, and simultaneously turning on the first and the third switches to measure the voltage of the second application terminal so as to measure the second resistance. A test device, characterized in that for calculating. 3. The method of claim 2,
The passive device test circuit may include a fourth switch connected between a third power supply terminal applying a third voltage and the first cell terminal, a third reference resistor connected between the fourth switch and the first cell terminal; A first voltage follower connected between the third reference resistor and the first cell terminal and an output terminal connected to the second application terminal; an output terminal of the first voltage follower and the second application; And a fifth switch connected between the terminals, and a sixth switch connected between the second cell terminal and the ground, to apply the third voltage to the third power supply terminal, and at the same time, the fourth to the fourth 6. The test apparatus of claim 1, wherein the first capacitor is calculated by measuring the voltage at the first cell terminal after a predetermined time has elapsed. The method of claim 3, wherein
The passive elements may include a second capacitor connected between the first and second application terminals, and a third cell connected between the second application terminal and the second cell terminal to which the source terminal of the first switching device is connected. Further comprising a capacitor;
The passive device test circuit may include a fourth reference resistor connected between the sixth switch and the second cell terminal, the fourth power supply terminal applying a fourth voltage and the second application terminal, and the non-inverting input terminal being connected to the second application terminal. A second voltage follower connected between a second application terminal and the fourth reference resistor, an output terminal connected between the first cell terminal, and a connection between the first cell terminal and an output terminal of the second voltage follower And a seventh switch and an eighth switch connected between the fourth reference resistor and the second application terminal to apply the fourth voltage to the fourth power supply terminal, and simultaneously 8 The test apparatus of claim 8, wherein after the predetermined time has elapsed, the second capacitor is calculated by measuring the voltage at the second application terminal. The method of claim 4, wherein
The passive device test circuit includes a ninth switch connected to a fifth power supply terminal applying a fifth voltage, a fifth reference resistor connected between the ninth switch and the first cell terminal, and a non-inverting input terminal. A third voltage follower connected between a first cell terminal and the fifth reference resistor and an output terminal connected to an inverting input terminal and the second cell terminal; between an inverting input terminal of the third voltage follower and the second cell terminal. And a tenth switch connected to the second power supply terminal and an eleventh switch connected between the second application terminal and the ground, applying the fifth voltage to the fifth power supply terminal, and simultaneously operating the ninth to eleventh switches. And turning on, after a predetermined period of time, measuring the voltage at the first cell terminal to calculate the third capacitor. 6. The method according to any one of claims 1 to 5,
And the passive device test circuit tests each of the passive devices without a switching operation in response to threshold voltages of the first and second switching devices. The method of claim 5, wherein
The passive device test circuit;
And setting the predetermined time equally when the capacities of the first to third voltage followers are the same. A passive element test method for testing said passive elements of said battery protection circuit using said test device as claimed in claim 5
Testing the first resistance using a first drop voltage generated across the first parasitic diode generated between the voltage applying terminal and the voltage reference terminal of the protection integrated circuit and the first reference resistor;
The second drop voltage generated at both ends of the second parasitic diode generated between the voltage applying terminal and the voltage sensing terminal of the protection integrated circuit, the second reference resistance and the measured first resistor. 2 test the resistance;
Disabling the second and third capacitors using the first voltage follower and testing the first capacitor using the third reference resistance and the measured first resistance;
Neutralizing the first and third capacitors using the second voltage follower and testing the second capacitors using the fourth reference resistor; next
Disabling the first and second capacitors using the third voltage follower, and testing the third capacitor using the fifth reference resistor. The method of claim 8,
The method comprising:
And wherein said battery protection circuit is processed before said protection integrated circuit, said switching circuit and said passive components are modularized and packaged into a battery pack.

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