KR20230171633A - Boost converter capable of detecting output short-circuit and electronic device having the same - Google Patents

Abstract

According to an aspect according to the technical idea of the present disclosure, an inductor with one end connected to a power supply, a first diode with one end connected to the inductor and the other end connected to a load, and one end connected between the inductor and the first diode, , a first switch that is switched by an input first control signal to charge or discharge the inductor, and a second switch that has one end connected to the load and turns off when a first output current of a preset size or more flows to the load. A boost converter is disclosed, including:

Description

Boost converter capable of detecting output short circuit and electronic device including same {BOOST CONVERTER CAPABLE OF DETECTING OUTPUT SHORT-CIRCUIT AND ELECTRONIC DEVICE HAVING THE SAME}

This disclosure relates to a boost converter capable of detecting a short circuit of an output terminal and an electronic device including the same.

A boost converter is a circuit used to increase the output voltage relative to the input voltage, and is also called a step-up converter or step-up converter.

Figure 1 is a circuit diagram of a general boost converter. Referring to FIG. 1, in the boost converter 100, when the switch 130 is turned on, the inductor 120 is charged as the current from the power source (Power) 110 flows toward the switch 130 (path ① in FIG. 1). ). At this time, the current charged in the output capacitor 150 does not flow in the reverse direction by the diode 140. Thereafter, when the switch 130 is turned off, the boost converter 100 discharges the current charged in the inductor 120 and adds it to the current from the power source 110 to generate a voltage greater than the voltage of the power supply unit 110. Generated (path ② in Figure 1). At this time, the output capacitor 150 may serve to absorb high frequencies.

The boost converter 100 as shown in FIG. 1 cannot prevent overcurrent from flowing to the load when an output short circuit and/or overload occurs, causing damage to component parts. This may cause additional failure of electronic devices including the boost converter 100 and may cause an increase in overall repair costs.

KR 10-1024599 B1, 2011.03.17

The technical task to be achieved by the technical idea of the present disclosure is to provide a boost converter and an electronic device including the same, which can prevent component damage by immediately detecting an output short-circuit and reduce repair costs and the possibility of additional accidents.

The technical problem to be achieved by the technical idea of the present disclosure is not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

In order to achieve the above object, according to an aspect according to the technical idea of the present disclosure, an inductor, one end of which is connected to a power supply; a first diode with one end connected to the inductor and the other end connected to a load; a first switch whose end is connected between the inductor and the first diode and is switched by an input control signal to charge or discharge the inductor; and a second switch, one end of which is connected to the load and turned off when a first output current greater than a preset amount flows through the load.

According to an exemplary embodiment, the boost converter may further include a power switch that connects or disconnects the power supply unit and one end of the inductor in response to an input power switch control signal.

According to an exemplary embodiment, the boost converter may further include a third switch that turns on when the first output current exceeds a preset level, and when the third switch turns on, the The second switch may be turned off and the input of the driving voltage for driving the power switch and the power switch control signal to the power switch may be released.

According to an exemplary embodiment, the boost converter may further include a load-side resistance member, one end of which is connected to the load, and when the second switch is turned off, a second output is provided to the load and the load-side resistance member. It may be configured to allow current to flow.

According to an exemplary embodiment, the boost converter may further include a fourth switch that turns on when the second output current exceeds a preset level, and when the fourth switch turns on, the It may be configured to maintain the input release state of the driving voltage and the power switch control signal to the power switch.

According to an exemplary embodiment, the boost converter may further include a resistance member, one end of which is connected to the power supply and the other end of which is connected to the power switch, wherein the power switch has one end connected to the inductor. , a first power switch whose other end is connected to the resistance member and is switched by an input first power switch control signal to connect or disconnect the inductor and the power supply unit through the resistance member; and a second power switch, one end of which is connected between the power supply and the resistance member, the other end of which is connected to the inductor, and which is switched by an input second power switch control signal to connect or disconnect the inductor and the power supply. May include ;.

According to an exemplary embodiment, the second power switch may be configured to turn on after the first power switch is turned on.

According to another aspect according to the technical spirit of the present disclosure, an electronic device including the above-described boost converter is disclosed.

According to the technical idea of the present disclosure, it is possible to provide a boost converter and an electronic device including the same that can immediately detect an output short circuit to prevent damage to parts of the boost converter circuit and reduce repair costs and the possibility of additional accidents. It works.

The effects that can be achieved by the embodiments of the technical idea of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned can be obtained by those skilled in the art from the description below. can be clearly understood.

In order to more fully understand the drawings cited in this disclosure, a brief description of each drawing is provided.
Figure 1 is a circuit diagram of a general boost converter.
Figure 2 is a circuit diagram of a boost converter according to an embodiment of the present disclosure.
Figure 3 is a flowchart of an output short-circuit detection operation of a boost converter according to an embodiment of the present disclosure.
FIG. 4 is a diagram illustrating switch states and current flow when a boost converter according to an embodiment of the present disclosure operates normally.
5 and 6 are diagrams for explaining switch states and current flow when the boost converter operates abnormally according to an embodiment of the present disclosure.
7 is an example circuit diagram of a boost converter according to the present disclosure.

The technical idea of the present disclosure can be subject to various changes and may have various embodiments, and specific embodiments will be illustrated in the drawings and described in detail through detailed description. However, this is not intended to limit the technical idea of the present disclosure to specific embodiments, and should be understood to include all changes, equivalents, and substitutes included in the scope of the technical idea of the present disclosure.

In explaining the technical idea of the present disclosure, if it is determined that a detailed description of related known technology may unnecessarily obscure the gist of the technical idea of the present disclosure, the detailed description will be omitted. Additionally, numbers (eg, first, second, etc.) used in the description of the present disclosure are merely identifiers for distinguishing one component from another component.

In addition, in the present disclosure, when a component is referred to as "connected" or "connected" to another component, the component may be directly connected or directly connected to the other component, but specifically Unless there is a contrary description, it should be understood that it may be connected or connected through another component in the middle.

In addition, terms such as “unit”, “unit”, “character”, “module”, etc. described in the present disclosure mean a unit that processes at least one function or operation, which is hardware or software or hardware and It can be implemented through a combination of software.

Additionally, we would like to clarify that the division of components in this disclosure is merely a division according to the main function each component is responsible for. That is, two or more components, which will be described below, may be combined into one component, or one component may be divided into two or more components for more detailed functions. In addition to the main functions it is responsible for, each of the components described below may additionally perform some or all of the functions handled by other components, and some of the main functions handled by each component may be performed by other components. Of course, it can also be carried out exclusively by .

Hereinafter, embodiments based on the technical idea of the present disclosure will be described in detail one by one.

Figure 2 is a circuit diagram of a boost converter according to an embodiment of the present disclosure.

Referring to FIG. 2, the boost converter 200 according to an embodiment of the present disclosure is composed of components for implementing the original boosting function, including a power supply unit (PS), an inductor (L), a first diode (D1), and a first diode (D1). 1 It may include a switch (Q#1) and a capacitor (C). Here, the power supply unit (PS) includes a rectifier circuit, switches, etc. for converting AC power into DC power and outputting it, and may be implemented integrated with the boost converter 200 or implemented as a separate device. Hereinafter, for convenience of explanation, the description will be made on the assumption that the power supply unit (PS) is integrated and implemented in the boost converter 200.

The first switch Q#1 may be turned on or off in response to a control signal (eg, pulse width modulation signal, PWM signal) input from a controller (not shown). When the first switch (Q#1) is turned on, the inductor (L) can be charged by the power provided from the power supply (PS). Afterwards, when the first switch (Q#1) is turned off by the control signal, both the power provided from the power supply unit (PS) and the power charged in the inductor (L) are transferred to the load (LOAD), thereby performing a boosting function. It can be implemented. The capacitor C can remove high frequencies generated by switching of the first switch Q#1.

The boost converter 200 is configured to prevent damage to the circuit by detecting overcurrent flowing due to a short circuit of the LOAD, etc., and includes a second switch (Q#2), a third switch (Q#3), and a third switch (Q#3). Can contain 4 switches (Q#4). The second to fourth switches (Q#2 to Q#4) will be described in more detail below along with a description of the short circuit detection operation.

The boost converter 200 is configured to prevent damage due to inrush current and may include a first power switch (POWER SW#1) and a second power switch (POWER SW#2). The first power switch (POWER SW#1) can be switched by the first power switch control signal input from the controller through the fifth switch (Q#5). Additionally, the second power switch (POWER SW#2) can be switched by a second power switch control signal input from the controller through the sixth switch (Q#6).

The boost converter 200 may include a second diode (D2), a third diode (D3), and a fourth diode (D4). These can prevent current from flowing backwards from the output side to the first and second power switches (POWER SW#1 and POWER SW#2). Accordingly, at least one of the first to third diodes D1 to D3 may be replaced with another configuration or may be omitted in some cases.

The boost converter 200 may include first to sixth resistors R1 to R6 as components for implementing a voltage distribution function, etc. More specifically, the first and second resistors (R1, R2) may be components for distributing the output voltage corresponding to the load (LOAD), and the third to sixth resistors (R3 to R6) may be used as a third switch. These may be configurations for switching of (Q#3) or fourth switch (Q#4). At least one of the first to sixth resistors R1 to R6 may be replaced with another configuration or may be omitted in some cases.

The boost converter 200 may include first and second thermistors TH1 and TH2. The first thermistor TH1 may be a resistance member for consuming inrush current, and the second thermistor TH2 may be a resistance member for consuming overcurrent that may occur when the LOAD is short-circuited. At least one of the first and second thermistors TH1 and TH2 may be replaced with another configuration such as a resistor.

Hereinafter, the operation of the boost converter 200 circuit according to an embodiment of the present disclosure will be described in more detail.

FIG. 3 is a flowchart of an output short-circuit detection operation of a boost converter according to an embodiment of the present disclosure, and FIG. 4 illustrates the switch state and current flow when the boost converter operates normally according to an embodiment of the present disclosure. 5 and 6 are diagrams for explaining the switch state and current flow when the boost converter operates abnormally according to an embodiment of the present disclosure.

First, referring to FIG. 3, steps S301 to S305 are an initial situation in which power from the boost converter 200 is connected to the power supply unit (PS) and input power is supplied from the power supply unit (PS) into the boost converter 200. It may be an operation for .

In step S301, input power may be supplied from the power supply unit (PS).

In step S303, the first power switch control signal is activated so that the first power switch (POWER SW#1) can be turned on. For example, when the first power switch control signal corresponding to a preset voltage level is activated, the fifth switch (Q#5) may be turned on. As the fifth switch (Q#5) is turned on, the first power switch control signal is input to the first power switch (POWER SW#1) and the first power switch (POWER SW#1) is turned on. You can. Accordingly, the inrush current generated when input power is supplied from the power supply unit (PS) may be consumed by the resistance component of the first thermistor (TH1).

In step S305, when a preset time has elapsed after the first power switch control signal is input to the first power switch (POWER SW#1), the first power switch (POWER SW#1) of the first power switch control signal ) is released, so the first power switch (POWER SW#1) can be turned off. Then, the second power switch control signal is activated so that the second power switch (POWER SW#2) can be turned on. For example, when the second power switch control signal corresponding to a preset voltage level is activated, the sixth switch (Q#6) may be turned on. As the sixth switch (Q#6) is turned on, the second power switch control signal may be input to the second power switch (POWER SW#2). Control of the turn-off state of the first power switch (POWER SW#1) and the turn-on state of the second power switch (POWER SW#2) prevents unnecessary power consumption after the inrush current is consumed in the first thermistor (TH1). This may be to prevent this from being wasted.

The operations of steps S301 to S305 described above may be repeatedly performed when the input power is supplied again after the input power supply from the power supply unit PS is released.

In step S307, it may be determined whether the boost converter 200 according to an embodiment of the present disclosure is operating normally. Specifically, it can be determined whether the boost converter 200 is operating normally by monitoring the size of the current (hereinafter referred to as the first output current IR5) supplied to the load (LOAD) when the boost converter 200 is operating. You can. This will be explained in more detail with reference to FIG. 4 .

Referring further to FIG. 4, during normal operation of the boost converter 200 according to an embodiment of the present disclosure, the first and second power switches (POWER SW#1 & POWER SW#2) and the first to sixth switches (POWER SW#1 & POWER SW#2) The status of Q#1 to Q#6) is as follows.

(1) POWER SW#1: OFF

(2) POWER SW#2: ON

(3) Q#1: Switching according to control signal (PWM)

(4) Q#2: ON

(5) Q#3: OFF

(6) Q#4: OFF

(7) Q#5: OFF

(8) Q#6: ON

In this case, the path of the first output current (IR5) flowing through the load (LOAD) may correspond to the dotted line ① shown in FIG. 4, and when the boost converter 200 is operating normally, the first output current (IR5) ) can be maintained at a value within a predetermined range.

As a result of monitoring the first output current (IR5), if the size of the first output current (IR5) exceeds a preset size, it may be determined that an overcurrent flows on the LOAD side due to an abnormality such as an output short circuit.

If it is determined that the boost converter 200 is operating abnormally due to overcurrent detection, the boost converter 200 switches the second and third switches (Q#2, Q#3), the first and By controlling the operating state of the second power switches (POWER SW#1, POWER SW#2), damage to internal elements of the boost converter 200 due to overcurrent can be primarily prevented.

Referring further to FIG. 5, in step S309, when the size of the first output current (IR5) is greater than or equal to a preset size, the third switch (Q#3) may be turned on. For example, the third switch (Q#3) may be a transistor formed to conduct when the voltage applied to the fifth resistor (R5) exceeds a preset voltage, and the third switch (Q#3) may be a transistor configured to conduct the first output. When the current (IR5) becomes greater than a certain value, it may be automatically turned on (see FIG. 7).

In step S311, the second switch (Q#2) may be turned off due to the turn-on of the third switch (Q#3). For example, if the second switch (Q#2) is a MOSFET and the gate voltage of the MOSFET corresponds to the third switch (Q#3), when the third switch (Q#3) is turned on, the second switch As the gate voltage of (Q#2) decreases, the second switch (Q#2) may be turned off (see FIG. 7).

In step S313, due to the turn-on of the third switch (Q#3), the first power switch (POWER SW#1) maintains the turn-off state and the second power switch (POWER SW#2) turns to It can be off. For example, when the third switch (Q#3) is turned on, the voltage corresponding to the third switch (Q#3) is lowered, so the first and second power switch control signals are connected to the third switch (Q #3) It flows in the direction. Accordingly, the first power switch (POWER SW#1) can maintain the turn-off state, and the second power switch (POWER SW#2) can be turned off.

Turn-on of the third switch (Q#3), turn-off of the second switch (Q#2), and turn-off state control of the first and second power switches (POWER SW#1, POWER SW#2) Accordingly, the path of the remaining current (current flowing in the circuit after turning off POWER SW#1 and POWER SW#2) may be changed from the direction of the second switch (Q#2) to the direction of the second thermistor (TH2) ( ② dotted line).

In step S315, the boost converter 200 uses the second and third switches (Q#2, Q#3) and the first and second power switches (POWER SW#1, POWER SW#2) during the above-described abnormal operation. To maintain control, the remaining current can be monitored. The remaining current may be consumed by the resistance component of the second thermistor (TH2) while flowing toward the second thermistor (TH2) after the second switch (Q#2) is turned off. Additionally, the remaining current may be consumed by the resistance component of the second thermistor (TH2). It may also flow through the sixth resistor (R6) connected in series with TH2). Accordingly, it can be confirmed whether a residual current of a certain size or more flows by detecting the second output current IR6 corresponding to the residual current. In this way, the size of the second output current (IR6) is monitored and the second and third switches (Q#2, Q#3) and the first and second power switches (POWER SW#1, POWER While maintaining the control state of SW#2), the first and second power switches (POWER SW#1, POWER SW#2) are restarted, thereby secondarily preventing damage to the internal elements of the boost converter 200. .

Referring further to FIG. 6, in step S317, when the second output current IR6 greater than a preset level is detected, the fourth switch Q#4 may be turned on. For example, as illustrated in FIG. 7, when the fourth switch (Q#4) is a BJT, the fourth switch is controlled by the magnitude of the voltage formed by the second output current (IR6) and the sixth resistor (R6). (Q#4) can be conducted. That is, if the second output current (IR6) is greater than a preset level, the fourth switch (Q#4) can be converted to the turn-on state.

In step S319, if the abnormal operation state in which the second output current (IR6) of a preset size or more is detected by the turn-on of the fourth switch (Q#4) continues to be detected, the second switch (Q#2) is turned on. While maintaining the turn-off state, the 5th and 6th switches (Q#5, Q#6) also maintain the turn-off state to turn the 2nd switch (Q#2) and the 1st and 2nd power switches (POWER SW#) 1, POWER SW#2) can be controlled to a protection state in which the turn-off state is maintained.

Meanwhile, when the driving voltage, first voltage switch control signal, and/or second voltage switch control signal are applied by the user, etc., the first and second power switches (POWER SW#1, POWER SW#2) are turned on again. The status is converted to allow the power supply (PS) and load (LOAD) to be reconnected. In other words, there is a possibility that the booster converter 200 will start operating.

In order to prevent this, the driving voltage of the first and second power switches (POWER SW#1, POWER SW#2) flows to the LOAD side through the third diode (D3), thereby reducing the first voltage due to the user's restart. And the driving voltage application operation of the second power switches (POWER SW#1, POWER SW#2) can be blocked.

In this way, the boost converter 200 according to an embodiment of the present disclosure prevents damage to components by immediately flowing the overcurrent to the bypass path when an overcurrent occurs due to an output short circuit, and maintains the bypass path formation until the overcurrent disappears. This has the effect of doubly preventing damage to circuit components by preventing restart by the user.

7 is an example circuit diagram of a boost converter according to the present disclosure.

Referring to FIG. 7, the booster converter 700 according to the present disclosure may include active elements such as BJTs and MOSFETs. To be more specific, the power switches (POWER SW#1, POWER SW#2) and the first switches (Q#1) to the sixth switches (Q#6) illustrated in FIG. 2 may be the following elements. .

(1) First power switch (POWER SW#1) and second power switch (POWER SW#2): Electronic switch driven by driving voltage (Vcc)

(2) First switch (Q#1), second switch (Q#2), fifth switch (Q#5), and sixth switch (Q#6): MOSFET

(3) Third switch (Q#3) and fourth switch (Q#4): BJT

Since the active elements and/or passive elements illustrated in FIG. 7 are merely examples, it is obvious that the scope of the present disclosure cannot be limited by their types. In addition, the description of each switch has already been described in detail, but it is summarized as follows.

(1) First power switch (POWER SW#1) and second power switch (POWER SW#2): driven by driving voltage (Vcc) and switched by the corresponding power switch control signal.

(2) First switch (Q#1): switched by control signal (PWM)

(3) Second switch (Q#2): The voltage (VR2) divided by the first and second resistors (R1, R2) becomes the gate voltage and switches.

(4) Third switch (Q#3): In the turn-on state of the second switch (Q#2), the voltage (VR5) applied to the fifth resistor (R5) becomes the base voltage and switches.

(5) Fourth switch (Q#4): In the turn-off state of the second switch (Q#2), the voltage (VR6) applied to the sixth resistor (R6) becomes the base voltage and switches.

(6) Fifth switch (Q#5): The first power switch control signal becomes the gate voltage and switches.

(7) Sixth switch (Q#6): The second power switch control signal becomes the gate voltage and switches.

As described above, the boost converter (200, 700) according to an embodiment of the present disclosure can prevent damage to parts of the boost converter (200, 700) by immediately detecting whether the load is short-circuited, thereby reducing repair costs. and reduce the possibility of further accidents.

Additionally, the boost converters 200 and 700 according to an embodiment of the present disclosure can be used in various electronic products that want to use a voltage higher than a commercial power supply. It is obvious that damage to components due to load short-circuiting of these electronic products can be prevented, thus reducing repair costs and the possibility of further accidents.

The description of the above-described embodiments is merely an example with reference to the drawings for a more thorough understanding of the present disclosure, and should not be construed as limiting the technical idea of the present disclosure.

In addition, it will be clear to those skilled in the art to which this disclosure pertains that various changes and modifications can be made without departing from the basic principles of the present disclosure.

200, 700: Booster converter

Claims (8)

An inductor whose end is connected to the power supply;
a first diode with one end connected to the inductor and the other end connected to a load;
a first switch, one end of which is connected between the inductor and the first diode, and which is switched by an input first control signal to charge or discharge the inductor; and
a second switch, one end of which is connected to the load and turned off when a first output current greater than a preset level flows to the load;
Including a boost converter.
According to paragraph 1,
A power switch that connects or disconnects one end of the power supply unit and the inductor in response to an input power switch control signal;
Further comprising a boost converter.
According to paragraph 2,
a third switch that turns on when the first output current exceeds a preset level;
Including more,
When the third switch is turned on, the second switch is turned off and the input of the driving voltage for driving the power switch and the power switch control signal to the power switch is released.
According to paragraph 3,
A load-side resistance member, one end of which is connected to the load;
Including more,
A boost converter configured to allow a second output current to flow through the load and the load-side resistance member when the second switch is turned off.
According to paragraph 4,
a fourth switch that turns on when the second output current exceeds a preset level;
Including more,
A boost converter configured to maintain the input release state of the driving voltage and the power switch control signal to the power switch when the fourth switch is turned on.
According to paragraph 2,
a resistance member with one end connected to the power supply and the other end connected to the power switch;
Including more,
The power switch is,
A first power switch whose one end is connected to the inductor and the other end is connected to the resistance member, and which is switched by an input first power switch control signal to connect or disconnect the inductor and the power supply unit through the resistance member; and
a second power switch, one end of which is connected between the power supply and the resistance member, the other end of which is connected to the inductor, and which is switched by an input second power switch control signal to connect or disconnect the inductor and the power supply;
Including a boost converter.
According to clause 6,
A boost converter configured to turn on the second power switch after the first power switch is turned on.
An electronic device including a boost converter according to claims 1 to 7.

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