100-500W isolation type high-speed switch control device, circuit and method

Abstract

The invention relates to the technical field of switch system control, in particular to a 100-500W isolation type high-speed switch control device, system and method, the 100-500W isolation type high-speed switch control device comprises an isolation type DC / DC converter and an MOSFET switch tube, the isolation type DC / DC converter is provided with five pins which are respectively an input end + Vin, an input end-Vin, a CNT remote control end, an output end + Vout and a grounding end GND, the input end + Vin and the input end-Vin are used for connecting externally applied DC voltage, the CNT remote control end is used for controlling the working state of the DC / DC converter, and the MOSFET switch tube is connected with the output end + Vout. According to the invention, the isolated DC / DC converter is used for providing drive for the switching tube MOSFET, the on-off control of the switching tube of the MOSFET is realized, the isolation control of a high-power circuit is further realized, and compared with a traditional relay, the use space is greatly reduced. And meanwhile, the MOSFET switch tube not only has lower on resistance and lower power consumption, but also is high in response speed and strong in anti-interference capability.

Description

Technical Field

[0001] The present invention relates to the technical field of switch system control, and in particular to a 100-500W isolated high-speed switch control device, circuit, and method. Background Art

[0002] Currently, traditional relays are still widely used in high-power isolated switch control to achieve mutual control between circuits. As an electrical control device, a relay operates based on the principle of electromagnetic induction. When current is applied to a coil, the magnetic field generated causes the control device to move, thereby opening or closing the relay switch.

[0003] The circuit principle of using relay to realize power switch control is as follows Figure 1 As shown. This relay is a normally open relay, meaning that when no current is applied to the relay coil, the relay is open, and when current is applied to the coil, the relay is closed. VDD provides a stable 5V voltage for the relay coil. This solution uses a transistor in the relay's electromagnetic coil to control the relay. When the CNT remote control terminal is at a high level of 5V, the transistor conducts, current flows through the coil, and the relay switch closes, connecting the incoming and outgoing lines. When the CNT remote control terminal is connected to GND, the transistor is cut off, no current flows through the relay coil, and the relay switch opens, disconnecting the incoming and outgoing lines. High-power isolation control is achieved by controlling the relay's on and off state.

[0004] When relays are used as control circuits in existing high-power isolated switch control systems, not only are their high power consumption, slow response speed, and complex structure limiting their applicability and requiring a large amount of space, but the relays also generate electromagnetic interference to surrounding electronic circuits when normally opening and closing the switch, making other devices more susceptible to malfunction. Summary of the Invention

[0005] In view of the problems in the prior art, the present invention provides a 100~500W isolated high-speed switch control device, circuit and method.

[0006] The present invention is achieved through the following technical solutions: A 100-500W isolated high-speed switch control device includes an isolated DC / DC converter and a MOSFET switch tube. The isolated DC / DC converter has five pins: an input terminal +Vin, an input terminal -Vin, a CNT remote control terminal, an output terminal +Vout, and a ground terminal GND. The input terminals +Vin and -Vin are used to connect to an externally applied DC voltage, the CNT remote control terminal is used to control the operating state of the DC / DC converter, and the gate of the MOSFET switch tube is connected to the output terminal +Vout.

[0007] Preferably, the input terminal +Vin is connected to the 5V positive input.

[0008] Preferably, the input terminal -Vin is connected to the 5V input ground.

[0009] Preferably, a discharge resistor is provided between the gate and source of the MOSFET.

[0010] Preferably, the resistance of the discharge resistor is between 1 kΩ and 5.1 kΩ.

[0011] Preferably, the control device sets different logics according to different usage conditions to control the connection between the incoming line and the outgoing line.

[0012] Preferably, when the CNT remote control terminal is at a high level of 5V, the output terminal +Vout outputs a 10V voltage to drive the MOSFET switch tube, the MOSFET switch tube is turned on, and its input and output lines are connected.

[0013] Preferably, when the CNT remote control terminal is connected to the ground terminal GND, there is no voltage output between the output terminal +Vout and the ground terminal GND, the MOSFET switch tube has no driving voltage, the MOSFET switch tube is cut off, and its input and output lines are disconnected.

[0014] A control circuit comprising the 100-500W isolated high-speed switch control device.

[0015] A control method for a 100-500W isolated high-speed switch control circuit. When the CNT remote control terminal is floating or at a high level of 5V, the 10V voltage at the output of the DC / DC converter provides a driving voltage for the MOSFET switch tube. The MOSFET switch tube is turned on, its input and output lines are connected, and the high-power circuit controlled by the MOSFET is turned on. When the CNT remote terminal is connected to GND, the DC / DC converter has no voltage output, the MOSFET switch tube has no driving voltage, the MOSFET switch tube is cut off, its input and output lines are disconnected, and the high-power circuit controlled by the MOSFET is disconnected.

[0016] Compared with the prior art, the present invention has the following beneficial effects: In a high-power isolated high-speed switch control device of the present invention, a positive input +Vin, a negative input -Vin, and a CNT remote control terminal form a control portion. A small control variable (such as current or voltage) of the control circuit is used to control the high-power circuit, establishing an isolated interactive relationship between the control circuit and the controlled circuit. The control circuit portion controls the DC / DC output state by controlling the voltage signal at the CNT remote control terminal of the isolated DC / DC converter. In the controlled circuit portion, the output voltage of the isolated DC / DC converter is used as the driving voltage for the MOSFET, and the on and off switching of the MOSFET switch is used to control the external circuit. In a system, the device can be used for automatic regulation, remote control, monitoring, various safety protection functions, and conversion circuits.

[0017] Furthermore, the high-power isolated high-speed switch control circuit proposed in the present invention can realize modular design. The module adopts a standard housing (5 pins) and is shorter and smaller than a relay. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a circuit schematic diagram of a power switch control system using a relay in the prior art; Figure 2 This is a schematic diagram of a 100-500W isolated high-speed switch control device of the present invention. DETAILED DESCRIPTION The present invention will be further described in detail below with reference to specific embodiments, which are intended to explain the present invention rather than to limit it.

[0019] The present invention discloses a 100~500W isolated high-speed switch control device, referring to Figure 2 , including an isolated DC / DC converter and a MOSFET switch tube. The isolated DC / DC converter has five pins, namely the input terminal +Vin, the input terminal -Vin, the CNT remote control terminal, the output terminal +Vout and the ground terminal GND. Among them, the input terminal +Vin and the input terminal -Vin are used to connect the externally applied DC voltage, the CNT remote control terminal is used to control the working state of the DC / DC converter, and the gate of the MOSFET switch tube is connected to the output terminal +Vout.

[0020] The operating process of an isolated DC / DC converter: When a 5V DC voltage is applied to the input terminals +Vin and -Vin, a stable 10V DC voltage is generated between the output terminals +Vout and GND, isolating the input and output terminals. The CNT remote terminal is used to control the operating state of the DC / DC converter: when the CNT remote terminal is left unconnected or at a high level of 5V, the DC / DC converter output terminal Vout normally outputs 10V.

[0021] In some embodiments, a discharge resistor R2 is provided between the gate and source of the MOSFET, so that the MOSFET switch tube can be discharged quickly at the moment of shutdown, thereby improving the response speed of the MOSFET switch tube.

[0022] A 100-500W isolated high-speed switch control device based on an isolated DC / DC converter controls the on / off switching of a MOSFET, thereby achieving isolated control of high-power circuits. The isolated DC / DC converter, as the core power module, converts the input DC voltage into an isolated, stable output voltage, providing a drive signal for the MOSFET. The MOSFET, in turn, controls the on / off switching of the high-power circuit based on the drive signal.

[0023] The present invention also discloses a control circuit including the 100~500W isolated high-speed switch control device. Compared with relays, the isolated high-speed switch control device proposed in the present invention can adopt a modular design in the circuit, and has the advantages of low height, small size, fast response speed, and high flexibility of use. Since the circuit controlled by the relay works based on the principle of electromagnetic induction, the response speed is from several milliseconds to tens of milliseconds, while the switching speed of MOSFET is from several microseconds to tens of microseconds, so its response speed is very fast; and the circuit controlled by the relay needs to be re-selected in different power application environments, which will greatly increase the volume and even affect the entire circuit layout. Compared with relays, MOSFETs are very small in size. In different usage environments, it is only necessary to replace different models of MOSFETs according to the specific situation, and the isolated DC / DC converter part does not need to be changed, which does not affect the overall layout of the circuit, greatly improving its flexibility of use.

[0024] The present invention also discloses a control method for a 100~500W isolated high-speed switch control device. The principle of the control method is as follows: Figure 2 As shown in the figure, when the CNT remote control terminal is floating or at a high level of 5V, the 10V voltage at the output end of the DC / DC converter provides a driving voltage for the MOSFET switch tube, the MOSFET switch tube is turned on, its input and output lines are connected, and the high-power circuit controlled by the MOSFET is turned on; when the CNT remote control terminal is connected to GND, the DC / DC converter has no voltage output, the MOSFET switch tube has no driving voltage, the MOSFET switch tube is cut off, its input and output lines are disconnected, and the high-power circuit controlled by the MOSFET is disconnected.

[0025] This invention uses an isolated DC / DC converter to drive the MOSFET switch, enabling on / off control of the MOSFET, thereby achieving isolated control of high-power circuits. Compared with traditional relays, this invention significantly reduces the required space. MOSFET switches not only have lower on-resistance and power consumption, but also offer fast response and strong anti-interference capabilities.

[0026] The above description is merely a preferred embodiment of the present invention and is not intended to impose any limitation on the technical solution of the present invention. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can also be subjected to several simple modifications and replacements, and these modifications and replacements are also within the scope of protection covered by the claims.

Claims

1. A 100~500W isolated high-speed switch control device, characterized in that: It includes an isolated DC / DC converter and a MOSFET switch tube. The isolated DC / DC converter has five pins, namely the input terminal +Vin, the input terminal -Vin, the CNT remote control terminal, the output terminal +Vout and the ground terminal GND. Among them, the input terminal +Vin and the input terminal -Vin are used to connect the externally applied DC voltage, the CNT remote control terminal is used to control the working state of the DC / DC converter, and the gate of the MOSFET switch tube is connected to the output terminal +Vout.

2. The 100~500W isolated high-speed switch control device according to claim 1, characterized in that: The input terminal +Vin is connected to the 5V input positive.

3. The 100~500W isolated high-speed switch control device according to claim 1, characterized in that: The input terminal - Vin is connected to the 5V input ground.

4. The 100-500W isolated high-speed switch control device according to claim 1, characterized in that: A discharge resistor is provided between the gate and source of the MOSFET.

5. The 100-500W isolated high-speed switch control device according to claim 1, characterized in that: The resistance of the discharge resistor is between 1 kΩ and 5.1 kΩ.

6. The 100-500W isolated high-speed switch control device according to claim 1, characterized in that: The control device sets different logics according to different usage conditions to control the connection between the incoming and outgoing lines.

7. The 100-500W isolated high-speed switch control device according to claim 6, characterized in that: When the CNT remote control terminal is at a high level of 5V, the output terminal +Vout outputs a 10V voltage to drive the MOSFET switch tube. The MOSFET switch tube is turned on, and its input and output lines are connected.

8. The 100-500W isolated high-speed switch control device according to claim 6, characterized in that: When the CNT remote control terminal is connected to the ground terminal GND, there is no voltage output between the output terminal +Vout and the ground terminal GND, the MOSFET switch tube has no driving voltage, the MOSFET switch tube is cut off, and its input and output lines are disconnected.

9. A control circuit comprising the 100-500 W isolated high-speed switch control device according to any one of claims 1 to 8.

10. A control method for a 100-500W isolated high-speed switch control device according to any one of claims 1 to 8, characterized in that: When the CNT remote control terminal is suspended or at a high level of 5V, the 10V voltage at the output of the DC / DC converter provides a driving voltage for the MOSFET switch tube. The MOSFET switch tube is turned on, its input and output lines are connected, and the high-power circuit controlled by the MOSFET is turned on. When the CNT remote terminal is connected to GND, the DC / DC converter has no voltage output, the MOSFET switch tube has no driving voltage, the MOSFET switch tube is cut off, its input and output lines are disconnected, and the high-power circuit controlled by the MOSFET is disconnected.

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