TWI763222B - An electric device within short circuit protection - Google Patents

Abstract

An electric device within short circuit protection comprises of an input end, an output end, a bias circuit and an electric actuation component. The bias circuit includes a first pin, a bias unit and a second pin. The bias unit couples to the first ping and the second pin. The first pin connect to the input end. The second pin connect to the output end. The electric actuation component includes a switch circuit and a control circuit. The switch circuit connection in parallel with the bias circuit. One end of the switch circuit connect to the first pin, other end of the switch circuit connect to the second pin. One end of the control circuit connect to the second pin. When the control circuit receive an work power, the switch circuit is conduct. When the control circuit doesn’t receive the work power, the switch circuit is abort conduction.

Description

Electronic devices with short circuit protection

An electronic device with a switch circuit, particularly an electronic device with short-circuit protection.

For electronic devices, a short circuit is a dangerous thing. When an abnormal connection occurs between the two contacts of the device, the two contacts that are in contact will flow through the current exceeding the rated value. Exceeding the rated current may cause circuit and electronic components to burn out. Common short-circuit protection mechanisms are over current protection and over temperature protection.

Overcurrent protection is achieved through current limit circuits or electronic components. Overcurrent protection is aimed at the magnitude of the current flowing through the aforementioned circuits or electronic components, so as to determine whether the rated current is exceeded. Over-temperature protection measures the temperature of a specific circuit area or electronic component. Although these two methods can serve the purpose of short-circuit detection, the setting cost of the two methods is relatively high, and the scope of protection is limited.

In addition, for circuits with connected batteries or capacitors, a short circuit will not only affect the circuit, but may also cause the battery or capacitor to explode. When the aforementioned protection mechanisms are triggered, the risk of short circuit can be reduced. However, when a short circuit occurs, there will be two effects on the battery. The first situation is the discharge of the battery, which will cause rapid discharge of the battery due to a short circuit. As a result, rapid discharge will shorten the life of the battery. The second situation is the charging of the battery. In the short-circuit state, if the battery is continuously charged, the battery temperature may be too high, causing the battery to explode.

In view of this, according to some embodiments, an electronic device with short-circuit protection is provided, which is characterized by protecting other circuits when the load circuit is short-circuited.

The electronic device with short circuit protection of this embodiment includes an input terminal, an output terminal and a bias circuit. The bias circuit has a first pin, a bias unit and a second pin, two ends of the bias unit are respectively coupled to the first pin and the second pin, the first pin is connected to the input end, and the second pin is connected to the output end; the electric actuating component has a switch circuit and a control circuit, the switch circuit is connected in parallel with the bias circuit, the end of the switch circuit is coupled to the first pin, the other end is coupled to the second pin, and the end of the control circuit is coupled to the second pin; wherein, when the control circuit interrupts receiving the input power, the switch circuit is disconnected. In some embodiments, the electronic device with short circuit protection can cause the electrically actuated component to instantly respond and disconnect the connected circuit according to the change in current caused by the short circuit.

In some embodiments, the control circuit at least includes a light-emitting diode, and when the voltage difference between the two ends of the control circuit is greater than an operating threshold, the light-emitting diode emits light. In some embodiments, a short circuit warning can be issued immediately, so as to inform the user that the load circuit is short circuited.

In some embodiments, the control circuit includes an optical coupling element. When the voltage difference between the two ends of the control circuit is greater than the operating threshold, the light emitting diode illuminates the optical coupling element, and the switch circuit is in a conducting state.

In some embodiments, the electronic device with short circuit protection includes a current limiting circuit, one end of the current limiting circuit is connected to the second pin, and the other end is connected to the control circuit.

In some embodiments, the control circuit includes an electromagnetic element, and the switch circuit includes a magnetic reed element. When the voltage difference between the two ends of the control circuit is greater than an operating threshold, the electromagnetic element generates an operating magnetic force, and the operating magnetic force of the electromagnetic element magnetically induces the magnetic reed element to make the switch The circuit is on. In some embodiments, where the electrically actuated component is not operating power, the switching circuit can ensure that it will switch to an open circuit.

In some embodiments, a current-limiting circuit is further included, including a first current-limiting resistor, a second current-limiting resistor, a third current-limiting resistor, and a current-limiting transistor, the electrical actuation component is connected to one end of the first current-limiting resistor, and the first Two ends of the two current-limiting resistors are respectively connected to the other end of the first current-limiting resistor and the base of the current-limiting transistor, one end of the third current-limiting resistor is connected to the other end of the first current-limiting resistor, and the collector of the current-limiting transistor Connect to the electrical actuation assembly.

In some embodiments, the control circuit receives the input power, and when the voltage difference between the two ends of the control circuit is greater than the operating threshold, the switch circuit is turned on.

In some embodiments, the current-limiting circuit further includes a Zener diode, the anode of the Zener diode is connected to the collector of the current-limiting transistor, and the cathode is connected to the input terminal. In some embodiments, the Zener diode can prevent reverse current flow to the current limiting circuit.

The electronic device with short circuit protection of this embodiment includes an input terminal, an output terminal, a bias circuit and a MOS transistor. The bias circuit has a first pin, a bias unit and a second pin, two ends of the bias unit are respectively coupled to the first pin and the second pin, the first pin is connected to the input end, and the second pin is connected to the output end; the source of the MOS transistor is coupled to the first pin, the drain of the MOS transistor is coupled to the output end, the gate of the MOS transistor is coupled to the second pin, and the gate of the MOS transistor is coupled to the second pin. The working voltage is input to the electrode, and the source electrode and the drain electrode of the MOS transistor are turned on; the voltage drop of the gate electrode of the MOS transistor is lower than the operating threshold, and the source electrode and the drain electrode of the MOS transistor are disconnected. In some embodiments, the response rate of MOS transistors is better than that of other types of semiconductor transistors, and MOS transistors can be placed in limited circuits. The electronic device with short circuit protection can make the electric actuating component respond instantly and disconnect the connected circuit according to the change of the voltage drop caused by the short circuit.

In some embodiments, the electronic device with short-circuit protection further includes a current-limiting circuit, including a first current-limiting resistor, a second current-limiting resistor, a third current-limiting resistor, and a current-limiting transistor, and the drain of the MOS transistor is connected to the first current-limiting resistor. One end of a current limiting resistor, two ends of the second current limiting resistor are respectively connected to the other end of the first current limiting resistor and the base of the current limiting transistor, and one end of the third current limiting resistor is connected to the other end of the first current limiting resistor , the collector of the current limiting transistor is connected to the gate of the MOS transistor.

In some embodiments, the electronic device with short circuit protection includes a first diode and a second diode, the anode of the first diode is connected to the anode of the second diode, and the cathode of the first diode is connected to The source of the MOS transistor and the cathode of the second diode are connected to the gate of the MOS transistor.

In some embodiments, the electronic device with short circuit protection includes a third diode, the anode of the third diode is connected to the source of the MOS transistor, and the cathode of the third diode is connected to the drain of the MOS transistor .

Please refer to FIG. 1A , which is a schematic diagram of an electronic device with short circuit protection according to some embodiments of the present invention. Hereinafter, the electronic device with short-circuit protection is simply referred to as the short-circuit protection device 100 . The short circuit protection device 100 in some embodiments includes an input terminal 110 , an output terminal 120 , a bias circuit 130 and an electrical actuation component 140 . The input terminal 110 can be connected to the DC power input terminal 111 , and the input terminal 110 is used for transmitting the input power from the DC power input terminal 111 . The output terminal 120 can be connected to a load circuit 121, and the load circuit 121 can be, but not limited to, a charger, a transformer, an electronic device or other circuit structures.

For example, the short-circuit protection device 100 may be disposed in a Universal Serial Bus (USB) connector of a data cable or a cable, as shown in FIG. 1B . The short-circuit protection device 100 can also be arranged inside the electronic device, for example, the short-circuit protection device 100 (at the dotted circle frame in FIG. 1B ) can be arranged between the USB socket and the circuit board of the mobile communication device in FIG. 1B . When the electronic device is short-circuited, the short-circuit protection device 100 can not only prompt the user, but also disconnect the operating current of the load circuit 121, so that the short-circuited circuit stops supplying power. The following describes the operation of the elements of the short-circuit protection device 100 of the present invention in the pre-processing state, the working state and the short-circuit state.

The preprocessing state is the period from when the input terminal 110 receives the input power to before the electrical actuation element 140 is enabled. The working state is that after the electrical actuating element 140 is enabled and the electrical actuating element 140 is connected to the line from the input end 110 to the output end 120 . When the load circuit 121 is short-circuited, this state is a short-circuit state. In the short-circuit state, the short-circuit protection device 100 will interrupt the communication of the electrical actuation assembly 140 to the input terminal 110 and the output terminal 120 .

The bias circuit 130 has a first pin 131 , a bias unit 133 and a second pin 132 . Two ends of the biasing unit 133 are respectively coupled to the first pin 131 and the second pin 132 , please refer to FIG. 1C . The first pin 131 of the bias circuit 130 is connected to the input end 110 , and the second pin 132 of the bias circuit 130 is connected to the output end 120 . When the bias circuit 130 is in the preprocessing state, the input power flows through the first pin 131 to the second pin 132 . In some embodiments, the biasing unit 133 at least includes a resistor 134 , a Zener diode 135 or a light emitting diode 136 . Taking the biasing unit 133 as a light-emitting diode as an example, during the preprocessing state, the input power will pass through the biasing circuit 130 to cause the biasing unit 133 to emit light. The user can know that the short circuit protection device 100 has started to operate through the light emitting diodes 136 of the bias circuit 130 .

The electrical actuation component 140 has a switch circuit 141 and a control circuit 142 . The switch circuit 141 is connected in parallel with the bias circuit 130 , one end of the switch circuit 141 is coupled to the first pin 131 , and the other end of the switch circuit 141 is coupled to the second pin 132 . One end of the control circuit 142 is coupled to the second pin 132 and the output end 120 , and the other end of the control circuit 142 is connected to the ground. In the preprocessing state, the control circuit 142 receives the input power from the second pin 132 . Please refer to FIG. 2A , which is a schematic diagram of a short circuit protection device according to some embodiments of the present invention. In the pre-processing state and the short-circuit state, the switch circuit 141 is both open, and the symbol “X” in FIG. 2A indicates the open circuit. In some embodiments, the switch circuit 141 includes an optical coupling element 141a, and at least one of the control circuits 142 includes a light emitting diode 142a.

In the preprocessing state, the control circuit 142 obtains the input power, so that the voltage difference between the two ends of the control circuit 142 is greater than the operating threshold, and the light emitting diode 142a is enabled to emit light, as shown by the current arrows in FIG. 2B and FIG. 2C . Generally speaking, the operating threshold depends on the operable voltage or current of the electrical actuating element 140 , for example, the operating threshold may depend on the minimum operating voltage of the light emitting diode 142a. The arrows in FIG. 2B and FIG. 2C represent the current transmission paths. FIG. 2B is a pre-processing state. Since the control circuit 142 does not receive input power, the switch circuit 141 is open.

Input power flows through bias circuit 130 to electrically actuated component 140 . The light emitting diode 142a can emit light, and the light emitting diode 142a illuminates the light coupling element 141a of the switch circuit 141, so that the switch circuit 141 turns on the input end 110 and the output end 120. The electrically actuated assembly 140 is thus switched from the preconditioning state to the working state. So the input power can flow to the input terminal 110 through the switch circuit 141, as shown in FIG. 2D. In the working state, no input power will pass through the bias circuit 130, so that the light emitting diodes 136 in the bias circuit 130 will not emit light.

In some embodiments, the short circuit protection device 100 includes an input terminal 110 , an output terminal 120 , a bias circuit 130 , a current limiting circuit 150 and an electrical actuating component 140 , please refer to FIG. 3 . The input terminal 110 transmits the input power from the DC power input terminal 111 . The output terminal 120 is connected to the load circuit 121 , and the output terminal 120 outputs the input power to the load circuit 121 . Two ends of the bias circuit 130 are respectively connected to the input terminal 110 and the current limiting circuit 150 . One end of the current limiting circuit 150 is connected to the second pin 132 of the bias circuit 130 and the output end 120 . The other end of the current limiting circuit 150 is connected to the electric actuating component 140 . The current limiting circuit 150 is used to adjust the input power to protect the electrical actuating element 140 . The current limiting circuit 150 at least includes a resistor 151 , and the impedance of the resistor 151 is determined according to the electrical actuation element 140 .

The electrical actuation assembly 140 includes a switch circuit 141 and a control circuit 142 . The control circuit 142 is connected to the switch circuit 141 in parallel. One end of the control circuit 142 is connected to the current limiting circuit 150, and the other end is connected to the ground terminal. One end of the switch circuit 141 is coupled to the first pin 131 , and the other end of the switch circuit 141 is coupled to the second pin 132 . The input power flows to the electrical actuating element 140 through the current limiting circuit 150 , so that the light emitting diode 142 a is enabled to emit light and the switch circuit 141 is turned on.

The load circuit 121 is connected to the output end 120 of the short-circuit protection device 100 . When the short-circuit protection device 100 is in the working state, the switch circuit 141 transmits the input power from the input terminal 110 to the output terminal 120 and the load circuit 121 , as shown in FIG. 2C . When the load circuit 121 is short-circuited, the short-circuit protection device 100 enters a short-circuit state. Since the load circuit 121 is short-circuited, the load circuit 121 can be regarded as being directly grounded, as shown in FIG. 4 . In FIG. 4 , the input and the ground terminal of the load circuit 121 are connected by a thick black line between the load circuit 121 and the output terminal 120 to indicate that the load circuit 121 is short-circuited.

In the working state, the input power should pass through the input terminal 110 , the electrical actuation component 140 , and the output terminal 120 to the load circuit 121 . In the short-circuit state, the input power will be directly grounded after passing through the bias circuit 130 and the output terminal 120 . Therefore, the current limiting circuit 150 and the electrical actuating element 140 will not have input power flowing therethrough. In other words, the input current does not flow through the electrically actuated assembly 140, causing the voltage of the control circuit 142 to drop to zero. Therefore, the voltage difference across the control circuit 142 will be lower than the operating threshold. Therefore, the light emitting diode 142a of the control circuit 142 cannot be enabled to emit light, so that the optical coupling element 141a of the switch circuit 141 is disabled, and the switch circuit 141 is open. In the short-circuit state, the input power will continue to flow through the bias circuit 130 to the ground terminal of the load circuit 121 . The light emitting diodes 136 of the bias circuit 130 will exhibit a constant brightness.

Since the time interval for switching from the preprocessing state to the operating state is short, the light-emitting time of the light-emitting diode 136 of the bias circuit 130 is short. In the short-circuit state, the light-emitting diode 136 of the bias circuit 130 continues to emit light. The user can judge whether the load circuit 121 is short-circuited through the light-emitting state of the light-emitting diode 136 of the bias circuit 130 .

In some embodiments, the control circuit 142 includes at least an electromagnetic element 142b, and the switch circuit 141 includes at least a reed element 141b, as shown in FIG. 5A . The magnetic spring element 141b is switched between a first position (not shown) and a second position (not shown). When the switch circuit 141 is in a non-operating state, the reed elements 141b are all located at the first position. When the reed element 141b is in the first position, the switch circuit 141 is open, so that the input power cannot flow to the output end 120 through the switch circuit 141 . One end of the electromagnetic element 142b may be connected to a power input source, wherein the power input source may be the DC power input terminal 111 or an external power source. In FIG. 5A for convenience, one end of the electromagnetic element 142b is connected to an external power source, but it is not limited thereto. When the switch circuit 141 is in the working state, the electromagnetic element 142b obtains the input power and generates a change in the magnetic flux. The reed element 141b is thus acted upon by the electromagnetic element 142b, so that the reed element 141b will switch from the first position to the second position. When the reed element 141b is in the second position, the input power can flow through the switch circuit 141 through the output terminal 120 to the output terminal 120 and the load circuit 121, as shown in FIG. 5B . The short-circuit protection device 100 is switched from the preprocessing state to the working state.

In some embodiments, the current limiting circuit 150 includes a first current limiting resistor 152a, a second current limiting resistor 152b, a third current limiting resistor 152c, a current limiting transistor 152d and a Zener diode 152e, please refer to FIG. 5C and shown in Figure 5D. The electrical actuating component 140 is connected to one end of the first current limiting resistor 152a. 5C, 5D and 5E are simplified circuit diagrams, the input terminal 110 is represented by VCC_IN, and the output terminal 120 is represented by VDD_IN. Two ends of the second current limiting resistor 152b are respectively connected to the other end of the first current limiting resistor 152a and the base of the current limiting transistor 152d. One end of the third current limiting resistor 152c is connected to the other end of the first current limiting resistor 152a. The collector of the current limiting transistor 152d is connected to the electrical actuation component 140 . The second current-limiting resistor 152b limits the magnitude of the current flowing through the current-limiting transistor 152d, so that the current-limiting transistor 152d controls the magnitude of the current flowing to the electrically actuated component 140 .

In the preprocessing state, the bias circuit 130 makes the input power pass through the first current limiting resistor 152a, the second current limiting resistor 152b and the current limiting transistor 152d, and the input power is finally directed to the electromagnetic element 142b. The electromagnetic element 142b obtains the input power, and generates a change in the magnetic flux, thereby driving the magnetic reed element 141b to switch from the first position to the second position, as shown in FIG. 5D . Since the electrical actuating component 140 is switched from the preprocessing state to the working state, the input power can be conducted to the output terminal 120 and the load circuit 121 through the switch circuit 141 .

The voltage division between the first current limiting resistor 152a and the third current limiting resistor 152c is used for triggering the electric actuating element 140 when a short circuit occurs. When the load circuit 121 is short-circuited, the voltage division of the first current-limiting resistor 152a to the third current-limiting resistor 152c will disable the current-limiting transistor 152d, and the input power will pass through the bias circuit 130 to the ground terminal, so that the input Power does not pass through the electrical actuation assembly 140 . Therefore, the magnetic reed element 141b will not be electromagnetically induced by the electromagnetic element 142b, so that the magnetic reed element 141b is switched from the second position to the first position, as shown in FIG. 5E . And the input power continues to pass through the bias circuit 130, as shown in FIG. 5E. Therefore, the light emitting diodes 136 of the bias circuit 130 will remain bright. The user can further know whether the load circuit 121 is short-circuited through the constant brightness of the light-emitting diode 136 .

In some embodiments, the short-circuit protection device 100 can realize the electrical actuation device 140 through a combination of Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET), as shown in FIG. 6A . The short circuit protection device 100 includes an input end 110 , an output end 120 , a bias circuit 130 and a MOS transistor 160 . The bias circuit 130 has a first pin 131 , a bias unit 133 and a second pin 132 . Two ends of the biasing unit 133 are respectively coupled to the first pin 131 and the second pin 132 , the first pin 131 is connected to the input end 110 , and the second pin 132 is connected to the output end 120 .

In FIG. 6A , an enhancement type-P MOSFET is used as an example, but in fact, an N-type MOS transistor or other types of semiconductor transistors can also be used. The source of the MOS transistor 160 is coupled to the first pin 131 , the drain of the MOS transistor 160 is coupled to the output terminal 120 , and the gate of the MOS transistor 160 is coupled to the second pin 132 . In the preconditioning state, the source and drain of the MOS transistor 160 are open, so the input power will flow through the bias circuit 130 .

The input power flows to the gate of the MOS transistor 160 through the bias circuit 130 . When the input power reaches the operating voltage of the MOS transistor 160 , the source and drain of the MOS transistor 160 are turned on. Therefore, the short-circuit protection device 100 is switched from the preprocessing state to the working state, and the input power will not flow through the bias circuit 130 , but instead flows through the source to the drain of the MOS transistor 160 to the output terminal 120 . Therefore, the input power can flow through the MOS transistor 160 at the input terminal 110 , and the input power is output to the load circuit 121 from the output terminal 120 .

When the load circuit 121 is in a short-circuit state, the input power will flow from the bias circuit 130 to the output terminal 120 , the load circuit 121 and the ground terminal. Since the load circuit 121 is short-circuited, the MOS transistor 160 is larger than the load circuit 121 . Therefore, the MOS transistor 160 will not receive input power. In the short-circuit state, the gate of the MOS transistor 160 is interrupted to receive the input power, so the MOS transistor 160 will interrupt the communication between the source and the drain.

In some embodiments, the reaction rate of MOS transistor 160 is better than that of other types of semiconductor transistors. Moreover, the occupied volume of the MOS transistor 160 is small, so it can be matched with the circuit design.

In some embodiments, the short circuit protection device 100 includes an input terminal 110 , an output terminal 120 , a bias circuit 130 , a current limiting circuit 150 and a MOS transistor 160 , as shown in FIG. 6B . In FIGS. 6B , 6C and 6D , for simplified circuit representation, the input terminal 110 is represented by VCC_IN, and the output terminal 120 is represented by VDD_IN. The bias circuit 130 has a first pin 131 , a bias unit 133 and a second pin 132 . Two ends of the biasing unit 133 are respectively coupled to the first pin 131 and the second pin 132 , the first pin 131 is connected to the input end 110 , and the second pin 132 is connected to the output end 120 .

The current limiting circuit 150 includes a first current limiting resistor 152a, a second current limiting resistor 152b, a third current limiting resistor 152c and a current limiting transistor 152d. The drain electrode of the MOS transistor 160 is connected to one end of the first current limiting resistor 152a, and the two ends of the second current limiting resistor 152b are respectively connected to the other end of the first current limiting resistor 152a and the base electrode of the current limiting transistor 152d. One end of the third current limiting resistor 152c is connected to the other end of the first current limiting resistor 152a. The collector of the current limiting transistor 152d is connected to the gate of the MOS transistor 160, and the emitter of the current limiting transistor 152d is connected to the ground terminal. After the input power passes through the voltage drop of the first current limiting resistor 152a, the second current limiting resistor 152b and the current limiting transistor 152d, the MOS transistor 160 can ensure that the obtained input power is within the working voltage.

In some embodiments, a first diode 161 a and a second diode 161 b are further disposed between the MOS transistor 160 and the current limiting circuit 150 , as shown in FIG. 6C . The anode of the first diode 161a is connected to the anode of the second diode 161b. The cathode of the first diode 161 a is connected to the source of the MOS transistor 160 . The cathode of the second diode 161b is connected to the gate of the MOS transistor 160 . The first diode 161a and the second diode 161b are used to limit the current flowing between the source and the gate, so as to ensure that the MOS transistor 160 will not be broken down due to excessive current.

In some embodiments, a third diode 161c is further disposed between the source and drain of the MOS transistor 160, as shown in FIG. 6D. The anode of the third diode 161c is connected to the source of the MOS transistor 160 . The cathode of the third diode 161c is connected to the drain of the MOS transistor 160 . The third diode 161c is used to prevent the reverse voltage flowing through the source and the drain, so as to ensure that the MOS transistor 160 will not be broken down by the reverse voltage.

In summary, the electronic device with short circuit protection provided by the present invention can be applied to various electronic devices or circuit structures, such as a charger, a data cable, a mainboard or a power management chip (power management IC). The short circuit protection device 100 has simple circuit components and low cost to set up. Therefore, when the load circuit 121 is short-circuited, the short-circuit protection device 100 can respond immediately, thereby protecting other circuits or batteries. In some embodiments, the light-emitting element of the short-circuit protection device 100 can prompt the user of the current operating state.

100: Short circuit protection device 110: Input terminal 111: DC power input terminal 120: output terminal 121: Load circuit 130: Bias circuit 131: first foot position 132: The second foot 133: Bias unit 134: Resistor 135: Diode 136: Light Emitting Diode 140: Electric Actuation Assembly 141: switch circuit 141a: Optical coupling element 141b: Magnetic Reed Element 142: Control circuit 142a: Light Emitting Diode 142b: Electromagnetic Components 150: Current limiting circuit 151: Resistor 152a: The first current limiting resistor 152b: Second current limiting resistor 152c: The third current limiting resistor 152d: Current limiting transistor 152e: Diode 160:MOS transistor 161a: first diode 161b: Second diode 161c: Third diode

[ FIG. 1A ] A schematic diagram of an electronic device with short circuit protection according to some embodiments of the present invention. [FIG. 1B] A schematic diagram of application fields of some embodiments of the present invention. [ FIG. 1C ] A schematic circuit diagram of a short circuit protection device according to some embodiments of the present invention. [ FIG. 2A ] A schematic diagram of a short-circuit protection device according to some embodiments of the present invention. [ FIG. 2B ] A schematic diagram of the flow of input power in the preprocessing state of some embodiments of the present invention. [ FIG. 2C ] A schematic diagram of the flow of input power in the preprocessing state of some embodiments of the present invention. [ FIG. 2D ] A schematic diagram of the flow of input power in the working state of some embodiments of the present invention. [ FIG. 3 ] A schematic circuit diagram of a short circuit protection device according to some embodiments of the present invention. [ FIG. 4 ] A schematic diagram of a short-circuit state of some embodiments of the present invention. [ FIG. 5A ] A schematic circuit diagram of a short circuit protection device according to some embodiments of the present invention. [ FIG. 5B ] A schematic diagram of the magnetic reed element switching the second position and the input power according to some embodiments of the present invention. [ FIG. 5C ] A schematic circuit diagram of a short circuit protection device according to some embodiments of the present invention. [ FIG. 5D ] A schematic diagram of the magnetic reed element switching the second position and the input power according to some embodiments of the present invention. [ FIG. 5E ] A schematic diagram of a short-circuit state of some embodiments of the present invention. [ FIG. 6A ] A schematic circuit diagram of a short circuit protection device according to some embodiments of the present invention. [ FIG. 6B ] A schematic circuit diagram of a short circuit protection device according to some embodiments of the present invention. [ FIG. 6C ] A schematic circuit diagram of a short circuit protection device according to some embodiments of the present invention. [ FIG. 6D ] A schematic circuit diagram of a short circuit protection device of some embodiments of the present invention.

110: Input terminal

111: DC power input terminal

120: output terminal

121: Load circuit

130: Bias circuit

131: first foot position

132: The second foot

134: Resistor

135: Diode

140: Electric Actuation Assembly

141: switch circuit

141a: Optical coupling element

142: Control circuit

142a: Light Emitting Diode

150: Current limiting circuit

151: Resistor

Claims (12)

An electronic device with short-circuit protection, which comprises: an input end; an output end; are respectively coupled to the first pin and the second pin, the first pin is connected to the input end, the second pin is connected to the output end; and an electrical actuating component having a switch circuit and a a control circuit, the switch circuit is connected in parallel with the bias circuit, one end of the switch circuit is coupled to the first pin, the other end is coupled to the second pin, and one end of the control circuit is coupled to the second pin The control circuit at least includes a light-emitting diode. When the voltage difference between the two ends of the control circuit is greater than an operating threshold, the light-emitting diode emits light; wherein, when the control circuit stops receiving an input power, the light-emitting diode is disconnected. switch circuit. The electronic device with short circuit protection as claimed in claim 1, wherein the switch circuit includes an optical coupling element, and when the voltage difference between the two ends of the control circuit is greater than the operating threshold, the light emitting diode illuminates the optical coupling element, The switch circuit is in an on state. The electronic device with short circuit protection as claimed in claim 1 or 2, comprising a current limiting circuit, one end of the current limiting circuit is connected to the second pin, and the other end is connected to the control circuit. The electronic device with short circuit protection as claimed in claim 1 or 2, wherein the control circuit receives the input power, and when the voltage difference between the two ends of the control circuit is greater than the operating threshold, the switch circuit is turned on. An electronic device with short-circuit protection, which comprises: an input end; an output end; respectively coupled to the first pin and the second pin, the first pin is connected to the input end, the second pin is connected to the output end; an electrical actuation component has a switch circuit and a control a circuit, the switch circuit is connected in parallel with the bias circuit, one end of the switch circuit is coupled to the first pin, the other end is coupled to the second pin, and one end of the control circuit is coupled to the second pin , the control circuit includes an electromagnetic element, the switch circuit includes a magnetic reed element, when the voltage difference between the two ends of the control circuit is greater than an operating threshold, the electromagnetic element generates an operating magnetic force, and the operating magnetic force of the electromagnetic element is a magnetic induction The magnetic reed element, the switch circuit is in an on state; and a current limiting circuit including a first current limiting resistor, a second current limiting resistor, a third current limiting resistor and a current limiting transistor, the electrical actuation The component is connected to one end of the first current-limiting resistor, the two ends of the second current-limiting resistor are respectively connected to the other end of the first current-limiting resistor and the base of the current-limiting transistor, and one end of the third current-limiting resistor is connected At the other end of the first current-limiting resistor, the collector of the current-limiting transistor is connected to the electric actuating component; wherein, when the control circuit stops receiving an input power, the switch circuit is disconnected. The electronic device with short circuit protection as claimed in claim 5, wherein the current limiting circuit further comprises a zener diode, the anode of the zener diode is connected to the collector of the current limiting transistor, and the cathode is connected to the input end. The electronic device with short circuit protection according to claim 5, wherein the control circuit receives the input power, and when the voltage difference between the two ends of the control circuit is greater than the operation threshold, the switch circuit is turned on. An electronic device with short-circuit protection, which comprises: an input end; an output end; respectively coupled to the first pin and the second pin, the first pin is connected to the input end, the second pin is connected to the output end; and a MOS transistor, the source of the MOS transistor is coupled to the first pin, the drain of the MOS transistor is coupled to the output end, the gate of the MOS transistor is coupled to the second pin, and the gate of the MOS transistor receives an input power , turn on the source electrode and the drain electrode of the MOS transistor; wherein, when the gate electrode of the MOS transistor stops receiving the input power, the source electrode and the drain electrode of the MOS transistor are disconnected. The electronic device with short circuit protection as claimed in claim 8, further comprising a current limiting circuit comprising a first current limiting resistor, a second current limiting resistor, a third current limiting resistor and a current limiting transistor, The drain of the MOS transistor is connected to one end of the first current-limiting resistor, the two ends of the second current-limiting resistor are respectively connected to the other end of the first current-limiting resistor and the base of the current-limiting transistor, and the third One end of the current limiting resistor is connected to the other end of the first current limiting resistor, and the collector of the current limiting transistor is connected to the gate electrode of the MOS transistor. The electronic device with short circuit protection as claimed in claim 9, comprising a first diode and a second diode, the anode of the first diode is connected to the anode of the second diode, and the first diode is connected to the anode of the second diode. The cathode of a diode is connected to the source of the MOS transistor, and the cathode of the second diode is connected to the gate of the MOS transistor. The electronic device with short-circuit protection as claimed in claim 9 or 10, comprising a third diode, the anode of the third diode is connected to the source of the MOS transistor, and the third diode has an anode connected to the source of the MOS transistor. The cathode is connected to the drain of the MOS transistor. An electronic device with short-circuit protection, which comprises: an input end; an output end; are respectively coupled to the first pin and the second pin, the first pin is connected to the input end, the second pin is connected to the output end; and an electrical actuating component having a switch circuit and a a control circuit, the switch circuit includes an optical coupling element, the switch circuit is connected in parallel with the bias circuit, one end of the switch circuit is coupled to the first pin, the other end is coupled to the second pin, the control circuit One end is coupled to the second pin; wherein, when the voltage difference between the two ends of the control circuit is greater than the operating threshold, the optical coupling element is enabled, and the switch circuit is in a conducting state; wherein, when the control circuit interrupts receiving As soon as power is input, the switch circuit is opened.

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