KR100691630B1 - An apparatus for driving lcd backlight with detecting type using jin-balancing loop - Google Patents

Abstract

An LCD backlight driving apparatus for detecting a voltage or a current using a JIN-balancing loop is provided to facilitate a design and fabrication and stably control feedback by detecting the voltage or current through the JIN-balancing loop having a low voltage. In an LCD backlight driving apparatus for detecting a voltage or a current using a JIN-balancing loop, a main transformer(200) supplies a driving current to a lamp unit(100) having a plurality of lamps(Lamp1 to Lampn). A JIN-balancing circuit includes a plurality of JIN transformers(JT1 to JTn) having a primary coil(L1) connected to one side of each of the plurality of lamps(Lamp1 to Lampn) of the lamp unit(100) and a secondary coil(L2) electrically connected to the primary coil(L1), a trans chain unit(310) serially connected through the secondary coil(L2) of the plurality of JIN-transformers(JT1 to JTn), and a chain connecting unit(320) forming a closed loop by connecting one end and the other end of the trans chain unit(310) to each other. A voltage detection circuit unit(410) includes first and second passive elements(P1,P2) serially connected to the chain connecting unit(320) in at least one connection node among a plurality of connection nodes between the plurality of JIN transformers(JT1 to JTn), and at least one voltage detecting circuit(411) detecting a voltage of the connection node of the first and second passive elements(P1,P2).

Description

Detecting LCD Backlight Drive Using Jin-Balanced Loop {AN APPARATUS FOR DRIVING LCD BACKLIGHT WITH DETECTING TYPE USING JIN-BALANCING LOOP}

1 is a diagram illustrating a first configuration of a conventional LCD backlight driving device.

2 is a diagram illustrating a lamp driving voltage characteristic of FIG. 1;

3 is a view illustrating a second configuration of a conventional LCD backlight driving device.

4 is a diagram illustrating a first configuration of an LCD backlight driving apparatus according to the present invention.

Figure 5 is a detailed illustration of the voltage detection circuit of the present invention.

6 (a) and 6 (b) are exemplary diagrams illustrating implementations of first and second passive elements in the voltage detection circuit unit of FIG. 4.

Figure 7 is a second configuration example of the LCD backlight driving apparatus according to the present invention.

8 (a) and 8 (b) are exemplary diagrams illustrating implementations of first and second passive elements in the voltage detection circuit unit of FIG.

Explanation of symbols on the main parts of the drawings

100: lamp unit 200: main transformer

310: trans chain portion 320: chain connection portion

300: true-balancing circuit portion 410: voltage detection circuit portion

411, 412, 413: voltage detection circuit 420: current detection circuit

500: feedback circuit unit 600: control unit

Lamp 1 ~ Lamp n: Lamp JT1 ~ JTn: Gene Trans

P1, P2: first and second passive elements P11, P21, P31: first passive elements

P12, P22, P32: second passive element R11, R12: first, second resistor

C11, C12: first and second capacitors R21, R22: first and second resistors

C21, C22: first and second capacitor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LCD backlight driving apparatus of a detection method using a gin-balancing loop, and in particular, a feedback current or a jin-balancing loop to form a driving current-balancing. The present invention relates to an LCD backlight driving apparatus of a detection method using a true-balancing loop which enables easy detection and design of a voltage and enables stable feedback control.

In general, as LCD monitors or LCD-TVs become larger in size, the number of lamps used for LCD backlights is gradually increasing. As a result, variations in driving currents between a plurality of lamps are generated, and thus, a balance method is widely adopted as a method for reducing such driving current variations.

A typical method of such a balance method is JIN-Balance, and even in an LCD backlight driver using this JIN-Balance method, feedback control must still be performed for stable driving of the circuit. .

Hereinafter, a conventional jin-balance LCD backlight driving apparatus will be described with reference to FIGS. 1 to 3.

1 is a first exemplary diagram of a configuration of a conventional LCD backlight driving apparatus.

The conventional LCD backlight driving apparatus shown in FIG. 1 includes a main transformer 12 for supplying a driving current to a lamp unit 11 including a plurality of lamps, and one side of each of the lamps of the lamp unit 11. Voltage detection for detecting a voltage applied to the gin-balancing circuit 13 in which a plurality of connected gin transformers JT1 to JTn are formed as closed loops, and the gin-trans JT1 to JTn of the gin-balancing circuit 13. The main transformer 12 is controlled in accordance with a circuit 14, a feedback circuit section 15 for converting the detected voltage from the voltage detection circuit 14 into a feedback voltage, and a feedback voltage from the feedback circuit section 15. It includes a control unit 16 to.

The voltage detection circuit 14 is connected to the ground via two resistors R1 and R2 and Rn1 and Rn2 connected to ground at one end of the gin-trans circuits JT1 to JTn of the gin-balancing circuit 13. The voltage Vd across the true-transformation JT1 to JTn is detected.

However, the problem of the conventional LCD backlight driving apparatus of FIG. 1 will be described with reference to FIGS. 1 and 2.

2 is a diagram illustrating a lamp driving voltage characteristic of FIG. 1.

Referring to FIG. 2, the conventional LCD backlight driving apparatus illustrated in FIG. 1 has an initial driving voltage that is high due to a lamp having a high impedance at the beginning of driving since each lamp is activated in an initial driving section. The voltage detected through the balancing circuit 13 also becomes high.

Therefore, since the unstable initial driving voltage is induced into the true-balance circuit, the detection voltage also becomes unstable according to the unstable initial driving voltage, and thus there is a problem that the feedback control based on the detection voltage also becomes unstable.

3 is a second exemplary diagram of a configuration of a conventional LCD backlight driving apparatus.

The conventional LCD backlight driving apparatus shown in FIG. 3 includes a main transformer 22 for supplying a driving current to a lamp unit 21 including a plurality of lamps, and one side of each of the lamps of the lamp unit 21. A jin-balancing circuit 23 in which a plurality of connected gin-trans circuits are formed as closed loops, a voltage detecting circuit 24 for detecting a voltage at a zero voltage connecting node of the plurality of lamps, and the voltage detecting circuit 24 And a control unit 26 for controlling the main transformer 22 according to the feedback voltage from the feedback circuit unit 25.

For example, the voltage detection circuit 14 may include a first capacitor C1 connected to one end of one of the two lamps and a second capacitor Cn connected to one end of the other of the two lamps. And a voltage Vd at the connection node NP of the first and second capacitors C1 and Cn.

In general, in a conventional LCD backlight driving apparatus, a lamp side which is a high voltage side is formed in an upper layer on a multilayer board, and a low side is formed in a lower layer of the multilayer board, wherein the lamp is driven by a high voltage of about 1.5 kV. When the lamp is driven by such a high driving voltage, if an abnormal situation occurs such as when the lamp is turned off, an arc may be generated between the high voltage side (lamp side) and the low side of the substrate. In order to prevent this, the high pressure side and the low side of the substrate should be spaced apart by a certain distance.

However, since the first and second capacitors C1 and Cn are formed between the high voltage side and the low side of the substrate, the high voltage side and the low side are electrically closer by the first and second capacitors C1 and C2. Since the first and second capacitors C1 and C2 are formed, a predetermined distance between the high voltage side and the low side must be maintained in order to prevent arc generation as described above. There is a problem that the volume of the substrate is increased, and accordingly, there are many restrictions in miniaturization.

SUMMARY OF THE INVENTION The present invention has been proposed to solve the above problems, and an object thereof is to accurately detect a feedback current or voltage by using a JIN-Balancing Loop that forms a driving current-balancing. The present invention provides an LCD backlight driving apparatus of a detection method using a true-balancing loop, which is easy to design and manufacture and enables more stable feedback control.

In order to achieve the above object of the present invention, the LCD backlight driving apparatus of the detection method using the true-balancing loop of the present invention, the main transformer for supplying a driving voltage to the lamp unit including a plurality of lamps; A plurality of gene transformers having a primary coil connected to one side of each of the plurality of lamps of the lamp unit and a secondary coil electromagnetically connected to the primary coil, and serially connected through the secondary coils of the plurality of gene transformers. A true-balancing circuit unit including a chain connected to each other and a chain connecting part connecting the one end and the other end of the trans chain part to form a closed loop; And first and second passive elements connected in series from the at least one connection node of the plurality of gin-trans circuit parts of the trans-chain part of the true-balancing circuit part to the chain connection part. And a voltage detecting circuit unit including at least one voltage detecting circuit for detecting a voltage at the connection node of the second passive element.

The apparatus of the present invention also includes: a feedback circuit section for converting the detected voltage from the voltage detection circuit section into a feedback voltage; And a control unit for controlling the main transformer according to the feedback voltage from the feedback circuit unit.

The voltage detection circuit unit includes a plurality of voltage detection units, and the plurality of voltage detection units output respective detection voltages to the feedback circuit unit.

The first and second passive elements of the voltage detection circuit portion have the same electrical characteristics as each other.

The first and second passive elements of the voltage detection circuit unit are formed of a first resistor and a second resistor.

The first and second passive elements of the voltage detection circuit unit may include a first capacitor and a second capacitor.

In addition, the LCD backlight driving apparatus of the detection method using a true-balancing loop of the present invention, the main transformer for supplying a driving voltage to the lamp unit including a plurality of lamps; A plurality of gene transformers having a primary coil connected to one side of each of the plurality of lamps of the lamp unit and a secondary coil electromagnetically connected to the primary coil, and serially connected through the secondary coils of the plurality of gene transformers. A true-balancing circuit unit including a chain connected to each other and a chain connecting part connecting the one end and the other end of the trans chain part to form a closed loop; And a first and second passive elements connected in series on the chain connection portion of the true-balancing circuit portion, and including a current detection circuit for detecting current at a connection node between the first and second passive elements. .

The apparatus of the present invention also includes: a feedback circuit section for converting a detection current from the current detection circuit into a feedback voltage; And a control unit for controlling the main transformer according to the feedback voltage from the feedback circuit unit.

The first and second passive elements of the current detection circuit are characterized by having the same electrical characteristics as each other.

The first and second passive elements of the current detection circuit are characterized by consisting of a first resistor and a second resistor.

The first and second passive elements of the current detection circuit are characterized by consisting of a first capacitor and a second capacitor.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings referred to in the present invention, components having substantially the same configuration and function will use the same reference numerals.

4 is a diagram illustrating a first configuration of the LCD backlight driving apparatus according to the present invention.

Referring to FIG. 4, the LCD backlight driving apparatus according to the present invention includes a main transformer 200, a true-balancing circuit unit 300, a voltage detection circuit unit 410, a feedback circuit unit 500, and a controller 600. .

The main transformer 200 supplies a driving voltage to the lamp unit 100 including a plurality of lamps Lamp1 to Lampn. In this case, the plurality of lamps Lamp1 to Lampn of the lamp unit 100 may be arranged in various ways.

The jin-balancing circuit unit 300 includes a plurality of primary coils connected to one side of each of the plurality of lamps Lamp1 to Lampn of the lamp unit 100 and a secondary coil electromagnetically connected to the primary coil. A trans chain unit 310 including the binary transformers JT1 to JTn and connected in series through secondary coils of the plurality of binary transformers JT1 to JTn, and one end and the other end of the trans chain unit 310. It comprises a chain connecting portion 320 to form a closed loop.

The voltage detection circuit unit 410 is connected to the chain connection unit 320 from at least one connection node among a plurality of connection nodes of the trans-chain unit 310 of the true-balancing circuit unit 300. And first and second passive elements P1 and P2 connected in series, and at least one voltage detection circuit for detecting a voltage at a connection node of the first and second passive elements P1 and P2.

The feedback circuit unit 500 converts the detection voltage from the voltage detection circuit unit 410 into a feedback voltage.

The control unit 600 controls the main transformer 200 according to the feedback voltage from the feedback circuit unit 500.

Meanwhile, the voltage detection circuit unit 410 may include a plurality of voltage detection units, which will be described with reference to FIG. 5.

5 is a detailed illustration of the voltage detection circuit of the present invention.

Referring to FIG. 5, the lamp unit 100 includes four lamps, and the jin-balancing circuit unit 300 includes four first to fourth jin-transs JT1 and JT2 corresponding to the four lamps. For example, the case including (JT3, JT4) will be described.

In FIG. 5, the voltage detection circuit unit 410 includes a first passive element P11 connected to a connection node between the first and second true-transities JT1 and JT2, and the first passive element P11. A second copper element (P21) for connecting to the chain connection unit 320, and outputs a detection voltage (Vd1) from the connection node (NP1) of the first and second passive elements (P1, P2) A first passive element P21 connected to a connection node between the first voltage detection circuit 411, the second and third binary-transformers JT2 and JT3, and the third passive element P21; A second voltage detection circuit including a fourth copper element P22 connected to the 320 and outputting a detection voltage Vd2 from a connection node NP2 of the third and fourth passive elements P21 and P22. 412, a fifth passive element P31 connected to the connection node between the third and fourth jin-trans JT3 and JT4, and the fifth passive element P31 to the chain connection unit 320. It includes a sixth copper element (P32) for connecting, 5 and 6 may include a passive element a third voltage detection circuit 412 for outputting a detected voltage (Vd3) in the access node (NP2) of (P31, P32).

The first and second passive elements P11 and P12, the third and fourth passive elements P21 and P22, and the fifth and sixth passive elements P31 and P32 of the current detection circuit provide accurate current detection. For this purpose, it is desirable to have the same electrical characteristics as each other. A detailed implementation example thereof will be described with reference to FIG. 6.

6A and 6B illustrate exemplary implementations of first and second passive elements of the voltage detection circuit of FIG. 4. Referring to FIG. 6A, the first and second passive elements P1 and P2 may include a first resistor R11 and a second resistor R12. Referring to FIG. 6B, the first and second passive elements P1 and P2 may include a first capacitor C11 and a second capacitor C12.

7 is a diagram illustrating a second configuration of the LCD backlight driving apparatus according to the present invention.

Referring to FIG. 7, the LCD backlight driving apparatus according to the present invention includes a main transformer 200, a true-balancing circuit unit 300, a current detection circuit unit 420, a feedback circuit unit 500, and a controller 600. .

The main transformer 200 supplies a driving voltage to the lamp unit 100 including a plurality of lamps Lamp1 to Lampn.

The jin-balancing circuit unit 300 includes a plurality of primary coils connected to one side of each of the plurality of lamps Lamp1 to Lampn of the lamp unit 100 and a secondary coil electromagnetically connected to the primary coil. A trans chain unit 310 including the binary transformers JT1 to JTn and connected in series through secondary coils of the plurality of binary transformers JT1 to JTn, and one end and the other end of the trans chain unit 310. It comprises a chain connecting portion 320 to form a closed loop.

The current detection circuit unit 420 may include first and second passive elements P1 and P2 connected in series on the chain connection unit 320 of the true-balancing circuit unit 300. 2 Current is detected at the connection node between passive elements P1 and P2.

The feedback circuit unit 500 converts the detection current from the current detection circuit unit 420 into a feedback voltage.

The controller 600 controls the main transformer 200 according to the feedback voltage from the feedback circuit unit 500.

It is preferable that the first and second passive elements P11 and P12 of the current detection circuit have the same electrical characteristics as each other for accurate voltage detection. A detailed implementation example thereof will be described with reference to FIG. 8.

8 (a) and 8 (b) are exemplary diagrams illustrating implementations of first and second passive elements of the voltage detection circuit unit of FIG. 7.

Referring to FIG. 8A, the first and second passive elements P1 and P2 of the current detection circuit unit 420 may include a first resistor R11 and a second resistor R12.

Referring to FIG. 8B, the first and second passive elements P1 and P2 of the current detection circuit unit 420 may be formed of a first capacitor and a second capacitor.

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

First, the operation of the LCD backlight driving apparatus of the present invention will be described with reference to FIGS. 4 to 6. In the LCD backlight driving apparatus according to the present invention, the main transformer 200 includes a plurality of lamps Lamp1 to Lampn. Supplying a high voltage driving voltage of approximately 1.5KV to the lamp unit 100 including.

In this case, the jin-balancing circuit 300 is electromagnetically connected to the primary coil L1 connected to one side of each of the plurality of lamps Lamp1 to Lampn of the lamp unit 100 and the primary coil L1. And a plurality of gene transformers JT1 to JTn having secondary coils L2 connected to each other, wherein the plurality of gene transformers JT1 to JTn are connected in series through the secondary coil L2. 310 and a chain connection part 320 that connects one end and the other end of the trans chain part 310 to form a closed loop.

The same current flows in the closed loop of the true-balancing circuit unit 300, and the same current balances the driving current flowing through the lamp unit 100 by mutual induction electromotive force of the plurality of gene-trans transistors JT1 to JTn. To form.

In the LCD backlight driving device operating as described above, the voltage detection circuit unit 410 includes at least one voltage detection circuit 411, and the voltage detection circuit 411 is configured of the true-balancing circuit unit 300. First and second passive elements P1 and P2 connected in series to the chain connection part 320 in at least one connection node among a plurality of connection nodes between the plurality of true-trans transformers of the transformer chain 310. The detection voltage Vd is output from the connection node NP of the first and second passive elements P1 and P2 to the feedback circuit unit 500 through the true-balancing circuit unit 300.

At this time, the feedback circuit unit 500 converts the detection voltage from the voltage detection circuit unit 410 into a feedback voltage. The control unit 600 controls the main transformer 200 according to the feedback voltage from the feedback circuit unit 500.

The voltage detection circuit unit 410 will be described in more detail with reference to FIG. 5.

In FIG. 5, when the voltage detection circuit unit 410 includes a first voltage detection circuit 411, a second voltage detection circuit 412, and a third voltage detection circuit 413, the first voltage detection circuit ( 411 is a first passive element (P11) connected to the connection node between the first and second jin-trans (JT1, JT2), and connecting the first passive element (P11) to the chain connector 320 The feedback circuit unit 500 outputs the detection voltage Vd1 at the connection node NP1 of the first and second passive elements P1 and P2 including the second copper element P21.

In addition, the second voltage detection circuit 412 may include a third passive element P21 connected to a connection node between the second and third true-trans transistors JT2 and JT3, and the third passive element P21. The detection voltage Vd2 is output from the connection node NP2 of the third and fourth passive elements P21 and P22, including a fourth copper element P22 connecting the chain connection unit 320 to the chain connection unit 320.

In addition, the third voltage detection circuit 413 includes a fifth passive element P31 connected to a connection node between the third and fourth true-trans transistors JT3 and JT4, and the fifth passive element P31. The detection voltage Vd3 is output from the connection node NP2 of the fifth and sixth passive elements P31 and P32, including the sixth copper element P32 connecting the chain connection unit 320 to the chain connection unit 320.

The first and second passive elements P11 and P12 of the current detecting circuit preferably have the same electrical characteristics as each other for accurate current detection. As shown in FIG. The first and second passive elements P1 and P2 may be formed of the first resistor R11 and the second resistor R12. Also, as shown in FIG. 2 The passive elements P1 and P2 may include a first capacitor C11 and a second capacitor C12.

Next, the operation of the LCD backlight driving apparatus of the present invention will be described with reference to FIGS. 7 to 8. As described above with reference to FIGS. 5 to 6, in the LCD backlight driving apparatus according to the present invention, a main transformer may be used. 200 supplies a driving voltage to the lamp unit 100 including a plurality of lamps Lamp1 to Lampn.

In this case, the jin-balancing circuit 300 is electromagnetically connected to the primary coil L1 connected to one side of each of the plurality of lamps Lamp1 to Lampn of the lamp unit 100 and the primary coil L1. And a plurality of gene transformers JT1 to JTn having secondary coils L2 connected to each other, wherein the plurality of gene transformers JT1 to JTn are connected in series through the secondary coil L2. 310 and a chain connection part 320 that connects one end and the other end of the trans chain part 310 to form a closed loop.

The same current flows in the closed loop of the true-balancing circuit unit 300, and the same current balances the driving current flowing through the lamp unit 100 by mutually induced electromotive force of the plurality of gene-trans transistors JT1 to JTn. To form.

In the LCD backlight driving device operating as described above, the current detection circuit unit 420 may include first and second passive elements P1 and P2 connected in series on the chain connection unit 320 of the true-balancing circuit unit 300. It includes, and detects the current in the connection node between the first and second passive elements (P1, P2) and outputs it to the feedback circuit unit (500).

In this case, the feedback circuit unit 500 converts the detection current from the current detection circuit unit 420 into a feedback voltage, and the controller 600 controls the main transformer according to the feedback voltage from the feedback circuit unit 500. Control 200.

The first and second passive elements P11 and P12 of the current detection circuit preferably have the same electrical characteristics as each other for accurate voltage detection. As shown in FIG. The first and second passive elements P1 and P2 of the detection circuit unit 420 may be formed of a first resistor R11 and a second resistor R12, and as shown in FIG. 8B. The first and second passive elements P1 and P2 of the current detection circuit unit 420 may be formed of a first capacitor and a second capacitor.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, but is defined by the claims, and the apparatus of the present invention may be substituted, modified, and modified in various ways without departing from the spirit of the present invention. It is apparent to those skilled in the art that modifications are possible.

According to the present invention as described above, in the LCD backlight driving apparatus of the detection method using the jin-balancing loop, by using a jin-balancing loop to form a driving current-balancing By accurately detecting the feedback current or voltage, the voltage or current is detected through the low-balance true-balancing loop, which is easier to design and manufacture, compared to the prior art of detecting the feedback voltage through a lamp having a high voltage. More stable feedback control is possible.

Claims (11)

A main transformer for supplying a driving voltage to a lamp unit including a plurality of lamps; A plurality of gene transformers having a primary coil connected to one side of each of the plurality of lamps of the lamp unit and a secondary coil electromagnetically connected to the primary coil, and serially connected through the secondary coils of the plurality of gene transformers. A true-balancing circuit unit including a chain connected to each other and a chain connecting part connecting the one end and the other end of the trans chain part to form a closed loop; And A first and a second passive element connected in series from the at least one connection node among the plurality of connection nodes between the plurality of gin-trans transformer parts of the gin-balancing circuit part to the chain connection part; 2 a voltage detecting circuit unit including at least one voltage detecting circuit for detecting a voltage at a connection node of a passive element LCD backlight driving device of the detection method using a jin-balancing loop, characterized in that it comprises a. The method of claim 1, A feedback circuit section for converting the detected voltage from the voltage detection circuit section into a feedback voltage; And Control unit for controlling the main transformer in accordance with the feedback voltage from the feedback circuit unit LCD backlight driving device of the detection method using a jin-balancing loop, characterized in that it further comprises. The voltage detecting circuit unit of claim 2, Including a plurality of voltage detectors, And a plurality of voltage detectors output the respective detected voltages to the feedback circuit unit. The method of claim 3, wherein the first and second passive elements of the voltage detection circuit portion, LCD backlight driving apparatus of a detection method using a jin-balancing loop, characterized in that they have the same electrical characteristics. The method of claim 4, wherein the first and second passive elements of the voltage detection circuit portion, An LCD backlight driving apparatus of a detection method using a true-balancing loop, comprising a first resistor and a second resistor. The method of claim 4, wherein the first and second passive elements of the voltage detection circuit portion, LCD backlight driving device of the detection method using a true-balancing loop, characterized in that the first capacitor and the second capacitor. A main transformer for supplying a driving voltage to a lamp unit including a plurality of lamps; A plurality of gene transformers having a primary coil connected to one side of each of the plurality of lamps of the lamp unit and a secondary coil electromagnetically connected to the primary coil, and serially connected through the secondary coils of the plurality of gene transformers. A true-balancing circuit unit including a chain connected to each other and a chain connecting part connecting the one end and the other end of the trans chain part to form a closed loop; And A current detection circuit including first and second passive elements connected in series on the chain connection portion of the true-balancing circuit portion, and detecting current at a connection node between the first and second passive elements; LCD backlight driving device of the detection method using a jin-balancing loop, characterized in that it comprises a. The method of claim 7, wherein A feedback circuit section for converting the detection current from the current detection circuit into a feedback voltage; And Control unit for controlling the main transformer in accordance with the feedback voltage from the feedback circuit unit LCD backlight driving device of the detection method using a jin-balancing loop, characterized in that it further comprises. The method of claim 7, wherein the first and second passive elements of the current detection circuit, LCD backlight driving apparatus of a detection method using a jin-balancing loop, characterized in that they have the same electrical characteristics. The method of claim 7, wherein the first and second passive elements of the current detection circuit, An LCD backlight driving apparatus of a detection method using a true-balancing loop, comprising a first resistor and a second resistor. The method of claim 7, wherein the first and second passive elements of the current detection circuit, LCD backlight driving device of the detection method using a true-balancing loop, characterized in that the first capacitor and the second capacitor.

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