KR20160114797A - Electronic Switching Device - Google Patents

Abstract

An embodiment of the present invention relates to an electronic switching device comprising: a load driving signal generator having an FET for generating a load driving signal for driving a vehicle load in accordance with a switching control signal; a switching control unit for generating and outputting a relay blocking signal when the battery (B+) is discharged, or when a users input operation is generated, or when the gate signal of the FET is out of a predetermined threshold voltage range, or when the voltage supply of the battery (B+) is blocked, by comprising a switching control signal output terminal which generates and outputs the switching control signal that controls the vehicle load by determining a duty value according to an input signal, and a relay blocking signal output terminal which outputs the relay blocking signal; and a gate protection unit provided in the gate front end of the FET to allow a gate signal input to the FET to flow to a ground when the relay blocking signal is input. The present invention is designed to block the discharge of batteries by blocking the batteries from being loaded before the batteries are discharged, thereby causing no inconvenience when a user uses a vehicle.

Description

TECHNICAL FIELD [0001] The present invention relates to an electronic switching device,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic switching device, and more particularly, to an electronic switching device for individually driving a plurality of electronic components mounted on an automobile.

Recently, many electric and electronic parts are mounted on automobiles, which increases the reliability of parts and provides various convenience to users. Therefore, the proportion of electric parts in automobiles is increasing. The use of electronic switching devices as electronic components has excellent characteristics such as high reliability, quick response, miniaturization and mechanical vibration-free. In the future, electronic switching devices will quickly replace mechanical switch relays.

An electronic switching device, for example, an electronic relay receives a control signal in the form of a direct current (DC) signal or a pulse width modulation (PWM) signal and outputs a direct current (DC) signal or a pulse width modulation Lt; / RTI >

In recent years, there has been an increase in the number of electric components mounted on automobiles such as a black box and a theft sensor, which means that the load and size of loads connected to the battery are increasing.

Accordingly, there is a great need for a protection device for preventing the discharge of the battery due to the consumption of the battery and a slight current consumption even after the start-up is turned off. Therefore, a battery disconnect switch (BDS) is provided to prevent the discharge of the battery. In the case of the conventional battery disconnect switch (BDS), a mechanical switch relay is used. However, There is a problem in that there is a limit in terms of lifetime and reliability.

There is also a battery disconnecting switch using an electronic switching device, but there is a problem that there is no self-protecting circuit that can prevent malfunction or breakage. That is, the electronic switching device may be damaged due to abrupt interruption due to the operation of the battery cut-off switch, and there is a problem that there is no self-protection circuit that can prevent such damage.

In addition, in the conventional airbag device, a single-wire method using gunpowder is used to prevent a secondary damage of an occupant caused by the operation of the airbag due to a vehicle collision. However, the necessity of a switching device requiring operation reliability owing to its safety problem arises .

Korean Patent Publication No. 10-2014-0055986

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to prevent a battery from discharging by blocking a battery with a load before discharging the battery, It is another object of the present invention to provide an electronic switching device that implements a blocking function to prevent damage and increase durability and ensure operation reliability.

An embodiment of the present invention provides a semiconductor device including: a load driving signal generator having a FET for generating a load driving signal for driving a vehicle load in accordance with a switching control signal; A switching control signal output terminal for generating and outputting the switching control signal for controlling a vehicle load by determining a duty value according to an input signal and a relay blocking signal output terminal for outputting a relay blocking signal, , Or a switching control unit for generating and outputting the relay shutoff signal when a user's input operation is generated or when the gate signal of the FET is out of a preset limit voltage range or when the voltage supply of the battery B + ; And a gate protection unit provided at a gate before the gate of the FET to allow the gate signal input to the FET to flow to the ground when the relay cutoff signal is input.

The electronic switching device includes a battery voltage detection unit for outputting a discharge warning signal when the voltage of the battery B + reaches a set critical discharge voltage, and the switching control unit switches the discharge warning signal And may generate and output a relay blocking signal when the discharge warning signal is input, including an input terminal.

Wherein the switching control unit comprises: a user first input terminal for receiving a user request through a pressing operation from a user; And a user second input terminal for receiving a user request from a user through a pressing operation, and when the forced first pressing operation of the user first input terminal exists, generates and outputs the relay blocking signal, And a user second input terminal for turning off the output of the relay cut-off signal when there is a pressing operation.

Wherein the switching control section includes an FET gate sensing terminal for receiving the gate signal of the FET, and when the gate signal of the FET input through the FET gate sensing terminal is not within the threshold voltage range, Can be generated and output.

The switching control unit includes a battery B + blocking signal input terminal for receiving a battery B + blocking signal from a battery blocking switch for blocking an output voltage of the battery B +, and the battery B + When the gate signal of the FET input through the gate sensing terminal is in the ON state, the relay blocking signal can be generated and output.

The switching control unit may perform a LIN communication with the electronic control unit to output a switching control signal for controlling the FET, the battery B + discharges, a user's input operation occurs, or the gate signal of the FET And generates and outputs the relay shutoff signal when the voltage exceeds the preset limit voltage range or when the voltage supply of the battery B + is interrupted.

Wherein the gate protection unit comprises: a relay blocking signal input terminal receiving the relay blocking signal; Gate blocking relay connected to battery (B +); And a gate cutoff switch connected to the relay cutoff signal input terminal for switching whether the battery voltage of the battery B + is applied to the gate cutoff relay according to a signal input through the relay cutoff signal input terminal have.

Wherein the gate blocking relay includes: a gate signal input terminal connected to a gate front end of the FET and receiving the gate signal; A ground connection terminal connected to ground; A relay coil having one end connected to the gate cutoff switch and the other end connected to the battery (B +); And a relay switching module provided between the gate signal input terminal and the ground connection terminal for turning on or off the connection of the gate signal input terminal and the ground connection terminal depending on whether the battery voltage is applied to the relay coil.

The gate protector may include a cathode connected in parallel with a node between the gate cutoff switch and the relay coil, and a zener diode having an anode connected to the ground.

The gate protection unit includes a diode having a cathode at one end and an anode at the other end connected to the relay blocking signal input terminal; And an RC parallel module provided between the cathode of the diode and the gate cutoff switch.

The gate breaking switch may be an NPN transistor.

The NPN transistor comprising: an emitter coupled to ground; A base connected to the RC parallel module; And a collector coupled to the relay coil.

The gate protection unit may include a blocking relay and a gate blocking switch for each of the branched signals by branching the relay blocking signal inputted through the relay blocking signal input terminal into two signals.

According to the embodiment of the present invention, the basic structure is an electronic relay system and has various advantages such as high reliability, noiselessness, quick response and the like compared with the mechanical relay system.

Also, by providing the gate protection unit 300, which is a protection circuit, in case the product is malfunctioned or damaged, noise signals that the product itself can not correspond to the gate of the FET, or parts of the electronic relay fail due to a vehicle accident, It is possible to prevent a malfunction of the product even if it is damaged due to abnormal operation of other products. Since the gate protection unit, which is a protection circuit, does not normally operate, the frequency of use is low, and the machine relay can be applied to satisfy the performance of the product at low cost.

In addition, the present invention can provide an electronic switching device applicable to an apparatus requiring high reliability and safety such as an airbag device through securing operating reliability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a device for driving a load such as a motor by an electronic switching device according to an embodiment of the present invention; FIG.
2 is a block diagram of a configuration of an electronic switching device according to an embodiment of the present invention;
3 is a conceptual block diagram of an electronic switching device according to an embodiment of the present invention;
4 is a circuit diagram of an electronic switching device according to an embodiment of the present invention;
FIG. 5 is a diagram illustrating an example of a switching control signal that varies a duty value according to a DC control input signal according to an embodiment of the present invention. FIG.
6 is a diagram illustrating an example of a switching control signal output according to a control input signal of PWM type according to an embodiment of the present invention.
7 is a diagram illustrating an example of a switching control signal output according to a high-level control input signal according to an embodiment of the present invention.
8 is a circuit diagram of a gate protection portion showing a state in which a gate blocking relay is disconnected from a ground and switched off according to an embodiment of the present invention.
FIG. 9 is a circuit diagram of a gate protection unit in which a gate blocking relay is switched on connected to a ground according to an embodiment of the present invention. FIG.
10 is a circuit diagram in which gate blocking relays are implemented in two channels according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, in order to explain the present invention in detail so that those skilled in the art can easily carry out the present invention. . Other objects, features, and operational advantages of the present invention, including its effects and advantages, will become more apparent from the description of the preferred embodiments. It should be noted that the same reference numerals are used to denote the same or similar components in the drawings.

1 is a diagram showing an apparatus for driving a load such as a motor by an electronic switching device according to an embodiment of the present invention.

An electronic switching device, for example, an electronic relay (E-Relay) receives a control signal (control input signal DC or PWM) in the form of a direct current (DC) signal or a pulse width modulation And outputs a PWM or DC type load driving signal to drive the load M. An electronic switching device, for example, an electronic relay (E-Relay) receives a control input signal and outputs a PWM or DC-type load driving signal to the load motor M. In response to the load driving signal, And the like.

In the embodiment of the present invention, the switching controller 100, which is a micro controller unit (MCU), performs the PWM or DC load driving signal output of the electronic switching device, Is used to determine whether there is a discharge of the battery B +, a user's input operation or a battery B +, and the current flowing to the FET of the electronic switching device is cut off to protect the FET device. Such an electronic switching device may be implemented as a single chip or may be implemented by other types of circuit means.

A battery cut-off switch (BDS) is connected between the car battery and electrical components. It protects the battery and the external load by cutting off the battery when the vehicle emergency occurs. For example, it is a main function to prevent the battery from being discharged due to some electric products consuming current of the battery even after the vehicle is turned off. A typical example of such electrical components is a car black box, which prevents the battery from discharging by shutting down the battery at the minimum necessary to perform operations such as door opening and start-up. The present invention is implemented as an electronic relay in order to increase the reliability of the product because the battery cut-off switch itself has a very important function to cope with a large current and cut off the power supply to the automobile electric products. Respectively. This will be described in detail below.

3 is a conceptual block diagram of an electronic switching device according to an embodiment of the present invention. FIG. 4 is a schematic block diagram of an electronic switching device according to an embodiment of the present invention. Circuit diagram of the switching device.

The electronic switching device of the present invention may include a switching control unit 100, a load driving signal generating unit 200, a gate protecting unit 300, and a battery B +. In addition, the constant voltage section (400). And a battery voltage sensing unit 500.

The battery B + is provided in the vehicle and supplies power to the switching control unit 100, the load driving signal generating unit 200, and the gate protecting unit 300. In particular, the battery B + can supply a stable voltage to the switching control unit 100 through the constant voltage unit 400.

The constant voltage unit 400 receives the power from the battery B + of the vehicle, generates a constant voltage, and provides the constant voltage to the switching control unit 100. For example, the constant voltage unit 400 receives a power supply voltage (for example, 12V) from the battery B + and converts it into a constant voltage (for example, 5V).

The load driving signal generating unit 200 is provided with a FET Q1 that generates a load driving signal for driving the vehicle load in accordance with the switching control signal. The load driving signal generating unit 200 includes a positive phase control module, a charge / discharge module, a local phase control module, a load output driving signal on / off module 230, and a FET Q1. The FET Q1 may be connected to a plurality of FETs in parallel according to the current capacity of the battery B +.

The constant phase control module may be implemented by a second switch SW2. The second switch SW2 receives a second switching control signal PWM2 having a phase opposite to that of the first switching control signal PWM1, And turns on / off the first switch SW1 as opposed to the first switch SW1, thereby providing / blocking the voltage provided by the battery B +. The second switch SW2 also receives the second switching control signal PWM2 of the PWM type of the switching control unit 100 as an ON switch when the input signal is high, . 5 to 7, it can be seen that the first switching control signal PWM1 and the second switching control signal PWM2 have opposite phases to each other. Therefore, since the driving of the second switch SW2 is driven in reverse to the first switch SW1, the loss of the current can be prevented. If the first switch SW1 receiving the first switching control signal PWM1 is turned on, a current is supplied to the first diode D1, the second resistor R2, the second capacitor C2, The second switching control signal PWM2 having a phase opposite to that of the first switching control signal is supplied to the second switch SW2 to turn off the second switch so that the power is turned on The current loss can be prevented.

The local phase control module may be implemented with a first switch SW1 which is connected to the switching drive signal input to the gate of the FET Q1 according to the first switching control signal PWM1 And turns on / off whether or not the discharge is performed. The first switch SW1 is a switch that is ON when the input first switching control signal PWM1 is high and switches from the switching control unit 100 And receives the control signal PWM1 to switch on / off (short-circuit / open). One end of the first switch SW1 is connected to the gate of the control terminal of the FET Q1 and the other end of the first switch SW1 is connected to the ground GND. When the first switch SW1 is turned on (short-circuited), the PWM-type switching drive signal input to the control terminal (gate) of the FET Q1 flows to the ground to serve as a discharge circuit.

The load driving signal generator 200 controls the output of the FET Q1 by adjusting the time constant (RC time constant) of the first charge / The load output driving signal ON / OFF module 230 adjusts the time constant of the first charging / discharging module 210 and adjusts the time constant of the second charging / discharging module 220 when the second charging / The number (RC time constant) can also be controlled to control the output of the FET Q1. In this embodiment, the case where the load driving signal generator 200 includes the first charge / discharge module 210 and the second charge / discharge module 220 will be mainly described. The load output driving signal on / off module 230 adjusts the charging / discharging time constant of the first charging / discharging module 210 and the second charging / discharging module 220 (320) to perform on / off driving of the FET Q1 . The load output driving signal on / off module 230 includes a second FET Q2 and a third FET Q3 connected in series and simultaneously receives the third switching control signal PWM3 from the switching controller 100. [

The second FET Q2 has a source connected to the source of the FET Q1 and a drain connected to the node between the drains of the first charge and discharge module 210 and the third FET Q3 I have. The gate (gate) of the second FET Q2 receives the third switching control signal from the switching controller 100. The third FET Q3 has a drain connected to the node between the other end of the first charge / discharge module 210 and the drain of the second FET Q2, and a source connected to the ground GND. The gate of the third FET Q3 receives the third switching control signal PWM3 from the switching control unit 100. [

Therefore, the second and third FETs Q2 and Q3 receive the PWM signal of the third switching control signal PWM3 to the respective gates and output the load output signal which is the source output of the FET Q1 to the charge / discharge cycle of the charge / The output of the FET Q1 can be controlled precisely by synchronously flowing to the load normally or flowing to the ground and conducting.

The first charging and discharging module 210 is an integrating circuit that receives the battery voltage from the battery B + and is composed of a first resistor R1 and a first capacitor C1 connected in series. And is an integrating circuit for generating a switching driving signal. Charging or discharging of the first capacitor C1 of the first charge / discharge module 210 is performed by switching the third FET Q3. One end of the first capacitor C1 is connected to the battery B + 500. In this embodiment, the first capacitor C1 is connected to the first diode D1 and the other end is connected to the first resistor R1 . One end of the first resistor R1 is connected to the first capacitor C1 and the other end is connected to the load output driving signal on / off module 230.

The first diode D1 is provided between the first charge / discharge module 210 and the battery B +. In this embodiment, the first diode D1 includes a first charge / discharge module 210 and a second charge / The anode of the first diode D1 is disposed on the side of the battery B + 500, more specifically, on the side of the battery (B +) 500, more specifically, between the node between the charge / discharge module 220 and the battery B + And a cathode of the first diode D1 is connected to a node between the first charge and discharge module 210 and the second charge and discharge module 220. [

The second charge / discharge module 220 has one end connected to the node between the first diode D1 and the first charge / discharge module 210 and the other end connected to the gate of the FET Q1 to provide a switching drive signal, And an integrating circuit of the second resistor R2 and the second capacitor C2 connected in parallel. That is, the second charging and discharging module 220 is an integrating circuit for generating a switching driving signal for operating the gate of the FET Q1, and includes a second resistor R2 and a second capacitor C2 in parallel. The second resistor R2 has one end connected to the node between the first diode D1 and the first charge / discharge module 210, and the other end connected to the gate of the FET Q1. The second capacitor C2 has one end connected to the second resistor R2 and the gate of the FET Q1, and the other end connected to the ground GND. That is, when the load driving signal generator 200 includes the second charging and discharging module 220, the second charging and discharging module 220 is connected to the FET Q1 together with the first charging and discharging module 210, And generates a switching driving signal for operating the gate of the switching transistor Q1.

In addition, a fifth diode D5 may be provided between the battery voltage and the second resistor R2. The fifth diode D5 is disposed between the first charge / discharge module 210 and the second charge / discharge module 220 between the battery B + and the second resistor R2. More specifically, the fifth diode D5 is connected between the battery B + The fifth diode D5 is disposed between the node between the first charge / discharge module 210 and the second charge / discharge module 220, and the fifth diode D5 is disposed between the node between the first charge / discharge module 210 and the battery B + The anode of the fifth diode D5 is connected to the node between the first charge and discharge module 210 and the first diode D1 and the cathode of the fifth diode D5 is connected to the second And is connected to a second resistor (R2) of the charge / discharge module (220). When the second charge / discharge module 220 is provided, the operation of charging the first capacitor C1 due to the conduction of the second FET Q2 through the fifth diode D5 is the same, It is possible to prevent the voltage of the integrating circuit composed of the second resistor R2 and the second capacitor C2 via the capacitor C1 from being partially discharged. The voltage of the integrating circuit constituted by the second resistor R2 and the second capacitor C2 is prevented from being partially discharged by preventing the voltage of the integrating circuit composed of the second resistor R2 and the second capacitor C2 from being partially discharged, It is possible to have a faster voltage rising operation speed than in the case of not including the diode D5 and to perform the same operation even if the integer values of the second resistor R2 and the second capacitor C2 are small.

The switching controller 100 (MCU, MICOM) receives an input signal for controlling each load through a multi-channel communication network and can generate a switching control signal according to an input signal.

For reference, the multi-channel communication network receives an operation command signal (hereinafter referred to as an 'individual input signal') of each load such as a tail lamp, a brake, etc. of a vehicle from an electronic control unit (ECU) Network. The multi-channel communication network may be implemented as a Local Interconnect Network (LIN) communication network in which one master communicates individually with a plurality of slaves via a slave identifier. Here, the LIN communication network is a communication method mainly used for a car communication cable, and is used for data transmission between an ECU, an active sensor of an automobile, and an active actuator. LIN is a simple, slow 12V, single-wire bus. LIN operates according to the master-slave principle, and the signal form and protocol are standardized. LIN is an address-based data transfer system through a single-wire bus. In the LIN data bus, up to 16 slaves can be connected to one main ECU (master).

Therefore, the switching control unit 100 according to the present invention generates a switching control signal for controlling the vehicle load by determining a duty value according to an input signal input through the LIN communication network, which is a multi-channel communication network, PWM2 terminal, PWM3 terminal).

Particularly, the switching control unit 100 according to the embodiment of the present invention includes a relay blocking signal output terminal F to which a relay blocking signal S1 is outputted and outputs a relay blocking signal output terminal F or the battery B + is discharged or a user's input operation is performed or the gate signal of the FET Q1 of the load driving signal generator 200 is out of a predetermined threshold voltage range, Or the supply of the voltage of the battery B + is interrupted, the relay shutoff signal S1 is generated and output.

The relay cutoff signal S1 may have a DC high / low signal form instead of a PWM signal. That is, when a high (for example, 5V) is output to the relay interception signal output terminal F, the relay interception signal S1 is outputted. If the relay interception signal output terminal F is maintained low (for example, 0V) The signal S1 can be set not to be output.

The gate protection unit 300 provided in parallel with the FET Q1 at the previous stage of the FET Q1 supplies the gate signal input to the gate of the FET Q1 to the ground GND The FET Q1 can be protected by preventing the gate signal from being applied to the gate of the FET Q1 and turning off the FET.

In order to output the relay cut-off signal S1, it is necessary to generate a discharge of the battery B +, a user input operation, a battery B +, and the like.

First, an example of outputting the relay cut-off signal S1 due to the discharge of the battery B + will be described. That is, an example in which the relay shutoff signal S1 is outputted when the battery B + is discharged and reaches the critical discharge voltage will be described. This critical discharge voltage may be set to a minimum voltage at which the vehicle can be started.

 When the battery B + falls to a predetermined threshold discharge voltage, the operation of the load (e.g., black box, etc.) must be stopped to prevent further discharging of the battery B +. For this purpose, the FET Q1 for outputting the load driving signal for driving the load must be turned off. To this end, the electronic switching device includes a battery voltage sensing unit 500 for outputting a discharge warning signal when the voltage of the battery B + reaches a preset critical discharge voltage.

The switching control unit 100 includes a discharge alarm signal input terminal to which a discharge alarm signal is input and generates a relay shutoff signal S1 when a discharge alarm signal is inputted through a discharge alarm signal input terminal to the gate protection unit 300 Output.

Next, an example of outputting the relay cut-off signal S1 by the user's input operation will be described.

(ON / OFF) signal from the LIN communication and receives the control command from the LIN communication provided through the LIN input terminal A, Receiving structure. However, it is also possible to implement a structure in which a command can be received by receiving a control signal input terminal from the user so that the user can perform manual control instead of LIN communication.

To this end, the switching controller 100 includes a user first input terminal B for receiving a user request through a pressing operation from a user, and a user second input terminal C for receiving a user request from the user through a pressing operation . The switching control unit 100 generates and outputs a relay blocking signal S1 when there is a forced pressing operation of the user first input terminal B and outputs a relay blocking signal S1 when the forced second pressing operation of the user second input terminal C occurs. (OFF) the output of the switch S1.

Therefore, when the user intends to forcibly terminate the operation of the FET Q1, the gate signal provided to the gate of the FET Q1 is flowed to the ground GND instead of the gate by clicking on the user first input terminal B . Conversely, if the user wishes to drive the operation of the FET Q1 again, by clicking on the user second input C, the gate signal provided to the gate of the FET Q1 is normally supplied to the gate of the FET Q1 can do.

Next, an example in which the blocking signal is outputted when the gate signal of the FET Q1 of the load driving signal generating unit 200 is out of the normal range will be described. The gate signal of the FET Q1 must have a threshold voltage range which is a normal range set on the characteristics of the FET device. When the gate signal of the FET is out of the normal voltage range, the FET Q1 may malfunction or be damaged. For example, if a high signal is sensed even though the gate signal passing through the second switch SW2, which is a local phase control module, is not ON, it is determined that the circuit is abnormal, S1 to generate and output the gate signal to turn on the gate blocking relay 310 in the gate protection unit 300 so that the gate signal provided to the gate of the FET Q1 can be flowed to the ground GND instead of the gate have. Therefore, the switching control unit 100 of the present invention includes the FET gate sensing terminal D receiving the gate signal of the FET Q1 and the gate signal of the FET Q1 input through the FET gate sensing terminal D, The gate signal provided to the gate of the FET Q1 flows to the ground GND instead of the gate to generate the relay shutoff signal S1 so that the FET Q1 is turned on, Lt; / RTI >

Next, an example will be described in which the relay shutoff signal S1 is outputted by blocking the voltage supply of the battery B +. The battery B + of the vehicle is provided with a battery disconnect switch (BDS) for blocking the voltage supply of the battery when the voltage of the battery B + falls below the set battery voltage, in order to prevent the battery B + ). The operation of this battery cut-off switch can cause damage to the FET Q1 if the battery voltage is not suddenly supplied to the FET Q1. Therefore, it is necessary to turn off the FET Q1 before the voltage supply of the battery B + is cut off.

To this end, the switching control unit 100 includes a battery cutoff signal input terminal E for receiving a battery cutoff signal from a battery cutoff switch that cuts off the output voltage of the battery B +. When the battery cutoff signal is input, The gate signal provided to the gate of the FET Q1 flows to the ground GND instead of the gate by generating and outputting the relay cutoff signal S1 when the gate signal of the FET input through the stage is ON So that the FET Q1 can be protected.

On the other hand, the switching control unit 100 performs LIN communication with the electronic control unit (ECU) to generate a switching control signal for controlling the FET Q1. However, if the above four cases occur, And outputs a signal S1 to protect the FET Q1. That is, even when the switching control signal for controlling the FET Q1 is output, the battery B + is discharged, or when a user's input operation is generated, or when the gate signal of the FET Q1 is out of the preset limit voltage range The gate signal supplied to the gate of the FET Q1 is supplied to the ground GND instead of the gate to generate a relay shutoff signal S1 to be supplied to the FET Q1, Q1).

On the other hand, the gate protection unit 300 is provided at the previous stage of the gate of the FET Q1, and when the relay shutoff signal S1 is inputted, the gate protection unit 300 performs the operation of flowing the gate signal inputted to the FET Q1 to the ground. FIG. 8 is a circuit diagram of a gate protection unit in which a gate blocking relay is disconnected from a ground according to an embodiment of the present invention. FIG. 9 is a circuit diagram of a gate protection relay according to an embodiment of the present invention. ON) is the circuit diagram of the gate protection part.

The gate protection unit 300 may include a relay blocking signal input terminal T1, a gate blocking relay 310, and a gate blocking switch Q4. In addition, the gate protection unit 300 may include a zener diode D6, a diode D3, and an RC parallel module R3-C3.

The relay blocking signal input terminal T1 is a terminal for receiving the relay blocking signal S1 output from the switching control unit 100. [

The gate cutoff switch Q4 is connected to the relay cutoff signal input terminal T1 and determines whether the battery voltage B + _ is applied to the gate cutoff relay 310 according to a signal input through the relay cutoff signal input terminal T1 The gate cut-off switch Q4, which is implemented as an NPN type transistor, includes an emitter E connected to the ground, a gate connected to the RC parallel module And a collector C connected to the relay coil 314. The base B is connected to the relay coil 314,

Therefore, when the gate cut-off signal is provided to the base B of the gate cut-off switch Q4 through the RC parallel module R3-C3, the gate cut-off switch Q4 is switched on, So that the provided battery voltage conducts the relay coil 314. As the current flows through the relay coil 314, the relay switching module 313 is connected to the ground as shown in FIG. 9, so that the gate signal can flow to the ground (GND).

The gate blocking relay 310 is connected to the battery B + and switches the gate signal inputted to the FET Q1 to ground when the relay blocking signal S1 is inputted through the relay blocking signal input terminal T1 It is a relay to perform. The gate blocking relay 310 includes a gate signal input terminal 311, a ground connection terminal 312, a relay coil 314, and a relay switching module 313.

The gate signal input terminal 311 is connected in parallel to the gate of the FET at the gate front end of the FET, and receives the gate signal. The ground connection terminal 312 is a terminal connected to the ground GND.

 The relay coil 314 is a coil whose one end is connected to the gate cutoff switch Q4 and the other end is connected to the battery B +. As the relay coil 314, various known relay coils 314 may be used, and a mechanical relay coil 314 using magnetic electromotive force may be used. For example, when no current flows through the relay coil 314, the relay switching module 313 is located at the OFF terminal and the relay switching module 313 is not connected to the ground terminal 312. [ On the other hand, when a current flows in the relay coil 314, the relay switching module 313 is switched to the ground terminal 312 by magnetic electromotive force by the magnetic electromotive force of the coil, so that the relay switching module 313 is connected to the ground terminal 312). For reference, the reason why the machine relay coil 314 is used with its lifetime and noise is that it does not operate in normal operation and performs operation only in case of abnormal operation.

The relay switching module 313 is provided between the gate signal input terminal 311 and the ground connection terminal 312 so that the gate signal input terminal 311 and the ground connection terminal 312 ) On or off. When the relay cut-off signal S1 is applied and the gate cut-off switch Q4 is turned on, a battery voltage is applied to the relay coil 314 so that a current flows. As a result, the gate signal input terminal 311 and the ground A connection (ON) is made between the connection ends 312. On the contrary, when the gate cut-off switch Q4 is turned off because the relay cut-off signal S1 is not applied, the battery voltage is not applied to the relay coil 314 and the gate signal input terminal 311 and the ground connection terminal (Not shown).

The gate protection unit 300 includes a cathode connected in parallel to a node between the gate cutoff switch Q4 and the relay coil 314 and a zener diode D6 having an anode connected to the ground diode). The Zener diode D6 is a diode having a breakdown voltage. When the battery voltage exceeds the breakdown voltage, the Zener diode D6 is turned on to protect the gate break switch Q4.

The gate protection unit 300 includes a diode D3 having a cathode at one end and an anode at the other end connected to the relay cut-off signal input terminal T1, a cathode of the diode D3 and a gate cutoff switch Q4 And an RC parallel module R3-C3 provided between the first and second parallel modules R3-C3. The RC parallel module is a module in which the resistor R3 and the capacitor C3 are connected in parallel and can protect the gate cutoff switch Q4 through the RC time constant.

Also, the diode D3 can cut off the current flowing backward to the switching control unit 100 through the relay blocking signal input terminal T1.

10, the gate protection unit 300 branches the relay blocking signal S1 input through the relay blocking signal input terminal T1 into two signals, And a shutoff switch Q4, respectively. That is, as shown in FIG. 10, the third diode D3, the third resistor R3, the third capacitor C3, the fourth transistor Q4, the sixth zener diode D6, the first relay coil A fourth resistor R4, a fourth capacitor C4, a fifth transistor Q5, a fifth transistor Q5, and a fourth transistor Q5, which are formed of a first relay switch module 314a and a first relay switching module 313a. Channel structure of a first gate protection unit consisting of a first Zener diode D7, a second relay coil 314b and a first relay switching module 313a. The reason why the two channels are used is to prevent the FET Q1 from being turned on by grounding the gate signal through another channel even if the gate protection unit 300 of one channel malfunctions.

As a result, by providing the gate protection unit 300, which is a protection circuit, in case a product malfunction or breakage occurs, a noise signal that can not be supported by the product itself may enter the gate of the FET, or a part of the electronic relay may fail due to a vehicle accident , It is possible to prevent a malfunction of the product even if it is damaged due to abnormal operation of other products.

Prior Art

Invention
purpose

On / off control using mechanical relays, no additional protection circuit for product failure
Electronic relay is used and the addition of protection circuit increases the reliability of the product
Configuration

No gate protection circuit
Added gate protection circuit
effect

Problems when the gate circuit malfunctions
Prevent malfunction when gate circuit breakdown occurs
difference

Inadequate reliability in case of product failure
Reliability in case of product failure

For reference, Table 1 summarizes the difference between the conventional mechanical relay prior art for outputting the load driving signal for driving the existing vehicle load and the electronic relay provided with the gate protection unit 300 of the present invention Table.

As a result, when turning off the FET Q1, the first switch SW1 is turned on to discharge the charged signal of the FET Q1. However, when the first switch SW1 or the FET Q1 does not normally operate (for example, the switching control pin is damaged or the PCB pattern is damaged), the FET Q1 fails to discharge the normally charged charge, May be damaged. In order to protect such a case, the switching relay of the gate protection unit 300 is placed so that the gate signal is connected to the ground (GND) at the time of the initial operation. In the abnormal condition, the FET Q1 is not operated, have.

The embodiments of the present invention described above are selected and presented in order to assist those of ordinary skill in the art from among various possible examples. The technical idea of the present invention is not necessarily limited to or limited to these embodiments And various changes, modifications, and equivalents may be made without departing from the spirit and scope of the present invention.

100:
200: a load driving signal generating unit
SW1: Local phase control module
SW2: Positive phase control module
210: first charge / discharge module
220: second charge / discharge module
300: gate protection part

Claims (13)

A load driving signal generator having an FET for generating a load driving signal for driving a vehicle load in accordance with a switching control signal;
A switching control signal output terminal for generating and outputting the switching control signal for controlling a vehicle load by determining a duty value according to an input signal and a relay blocking signal output terminal for outputting a relay blocking signal, , Or a switching control unit for generating and outputting the relay shutoff signal when a user's input operation is generated or when the gate signal of the FET is out of a preset limit voltage range or when the voltage supply of the battery B + ; And
A gate protection unit provided at a gate before the gate of the FET to allow a gate signal input to the FET to flow to a ground when the relay shutoff signal is input;
Lt; / RTI >
The method according to claim 1,
The electronic switching device includes a battery voltage detector for outputting a discharge warning signal when a voltage of the battery B + reaches a set critical discharge voltage,
Wherein the switching control unit includes a discharge alarm signal input terminal to which the discharge alarm signal is input to generate and output a relay shutoff signal when the discharge alarm signal is input.
The method according to claim 1,
Wherein the switching control unit comprises: a user first input terminal for receiving a user request through a pressing operation from a user; And a user second input for receiving a user request via a push operation from a user,
A second user input terminal for turning off the output of the relay cutoff signal when there is a forcible pressing operation of the user second input terminal; ;
/ RTI >
The method according to claim 1,
Wherein the switching control section includes an FET gate sensing terminal for receiving the gate signal of the FET, and when the gate signal of the FET input through the FET gate sensing terminal is not within the threshold voltage range, And outputs it.
The method of claim 4,
The switching control unit includes a battery B + blocking signal input terminal for receiving a battery B + blocking signal from a battery blocking switch for blocking an output voltage of the battery B +, and the battery B + And generates and outputs the relay shutoff signal when the gate signal of the FET input through the gate detection terminal is in the ON state.
The method according to claim 1,
The switching control unit may perform a LIN communication with the electronic control unit to output a switching control signal for controlling the FET, the battery B + discharges, a user's input operation occurs, or the gate signal of the FET And generates and outputs the relay shutoff signal when the voltage of the battery (B +) is exceeded or the voltage of the battery (B +) is blocked.
[2] The apparatus according to claim 1,
A relay blocking signal input terminal receiving the relay blocking signal;
Gate blocking relay connected to battery (B +); And
A gate cutoff switch connected to the relay cutoff signal input for switching whether the battery voltage of the battery B + is applied to the gate cutoff relay according to a signal inputted through the input terminal of the relay cutoff signal;
/ RTI >
8. The apparatus according to claim 7,
A gate signal input terminal connected to a front end of the gate of the FET and receiving the gate signal;
A ground connection terminal connected to ground;
A relay coil having one end connected to the gate cutoff switch and the other end connected to the battery (B +); And
A relay switching module provided between the gate signal input terminal and the ground connection terminal for turning on or off the connection of the gate signal input terminal and the ground connection terminal depending on whether the battery voltage is applied to the relay coil;
/ RTI >
9. The apparatus of claim 8,
A cathode connected in parallel with a node between the gate cutoff switch and the relay coil, and a cathode connected to the ground;
Lt; / RTI > 9. The apparatus of claim 8,
A diode having a cathode at one end thereof and having an anode connected to the relay blocking signal input terminal at the other end; And
An RC parallel module provided between the cathode of the diode and the gate cutoff switch;
Lt; / RTI >
11. The apparatus of claim 10,
Type transistor is an NPN-type transistor.
12. The NPN transistor according to claim 11,
An emitter connected to ground;
A base connected to the RC parallel module; And
A collector connected to the relay coil;
Lt; / RTI >
[12] The apparatus of claim 7,
Wherein the relay interrupting signal input through the relay interrupting signal input terminal is branched into two signals and each of the interrupting relay and the gate interrupting switch is provided for each of the branched signals.

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