A live plug circuit and system
By adding short pins and a control circuit design to the plug-in, the problems of instantaneous high current and electric sparks during hot-plugging are solved, achieving stable power supply and fast plugging/unplugging.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SONOSCAPE MEDICAL CORP
- Filing Date
- 2025-05-12
- Publication Date
- 2026-06-12
AI Technical Summary
During hot-plugging, existing technologies cannot effectively avoid instantaneous high current and electric sparks, which can lead to increased contact impedance of the connector, overheating, or even failure to supply power.
By adding short pins to the plug-in, the control circuit design ensures that the long pins make electrical contact with the plug-in first, followed by the short pins, thus controlling the conduction state of the switching unit, avoiding instantaneous large currents, and converting it to non-energized plugging and unplugging.
It effectively suppresses instantaneous high current, eliminates arcing of plug-in contacts, ensures stable power supply to the connector, and is suitable for scenarios involving rapid plugging and unplugging.
Smart Images
Figure CN224355829U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of circuit technology, and more particularly to a hot-swappable circuit and system. Background Technology
[0002] Electrical equipment is often powered by hot-plugging connectors. This hot-plugging generates a large instantaneous current, exceeding the connector pins' current limits. Repeated hot-plugging increases the pin impedance, leading to problems such as reduced input voltage and heat buildup causing damage to the connectors. Existing technologies employ methods such as... Figure 1 The current soft-start solution addresses the issue of transient high current by using an input capacitor to prevent the transient high current from directly acting on the electrical equipment. However, in hot-plug scenarios, although the electrical equipment is protected from high current damage, at the moment plug A and plug B are connected, the input capacitor undergoes a charging process, such as... Figure 2 As shown in the schematic diagram of live insertion and removal current, the waveforms of voltage Vcap and current Icap at the moment of plug insertion show an instantaneous peak in current. Under these circumstances, it is very easy for sparking to occur at the moment plug A and plug B come into contact. Once sparking occurs, after repeated occurrences, the contact resistance of the connector will increase, and when a large current passes through it, it will heat up, which will cause the connector to turn black at the connection point, or even fail to supply power.
[0003] Therefore, there is a need for a hot-plug circuit that can eliminate instantaneous high current and electric sparks during hot-plugging. Utility Model Content
[0004] Therefore, it is necessary to provide a hot-plug circuit that can eliminate instantaneous high current and electric sparks during hot-plugging.
[0005] An embodiment of this application provides a hot-swappable circuit, which includes: a first plug-in, a second plug-in, a control circuit, a switching unit, and an input capacitor that are mated and plugged in.
[0006] The first plug-in includes a long pin and a short pin with positive polarity, and the long pin and the short pin are electrically connected;
[0007] The second plug-in is connected to the input terminal of the control loop, the output terminal of the control loop is connected to the switching unit, and the switching unit is also connected to the input capacitor;
[0008] When the first plug-in and the second plug-in are connected, the long pin is inserted into the second plug-in first, and the control circuit controls the switching unit to be in the off state; the short pin is then inserted into the second plug-in, and the control circuit controls the switching unit to be in the on state to charge the input capacitor.
[0009] More preferably, the second insert includes a long needle end and a short needle end;
[0010] When the first plug-in and the second plug-in are connected, the long pin first makes electrical contact with the long pin end, and the short pin then makes electrical contact with the short pin end.
[0011] More preferably, the control loop includes a first control loop and a second control loop, the input terminal of the first control loop is connected to the second plug-in, the output terminal of the first control loop is connected to the input terminal of the second control loop, and the output terminal of the second control loop is connected to the switching unit.
[0012] More preferably, the first control loop includes a first switch control circuit and a second switch control circuit.
[0013] The first input terminal of the first switch control circuit is connected to the long needle end, the input terminal of the second switch control circuit is connected to the short needle end, the output terminal of the second switch control circuit is also connected to the second input terminal of the first switch control circuit, and the output terminal of the first switch control circuit is connected to the input terminal of the second control loop.
[0014] The second switch control circuit is used to control the operating state of the first switch control circuit.
[0015] More preferably, the first switch control circuit includes a first resistor, a second switch transistor, and a fourth switch transistor;
[0016] One end of the first resistor is connected to the end of the long needle to form a first connection point, the other end of the first resistor is connected to the control terminal of the fourth switch, the first end of the fourth switch is connected to the control terminal of the second switch, and the second end of the fourth switch is grounded.
[0017] The first end of the second switch is connected to the first connection point, and the second end of the second switch is connected to the input terminal of the second control loop.
[0018] More preferably, the second switch control circuit includes a third switch transistor and a first voltage divider circuit; the first voltage divider circuit includes a sixth resistor and a seventh resistor;
[0019] One end of the seventh resistor is connected to the short needle end, and the other end of the seventh resistor is connected to one end of the sixth resistor to form a first voltage divider connection point. The other end of the sixth resistor is grounded.
[0020] The control terminal of the third switch is connected to the first voltage divider connection point, the first end of the third switch is connected to the other end of the first resistor, and the second end of the third switch is grounded.
[0021] More preferably, the second control loop includes a second voltage divider circuit, which includes a second resistor and a fifth resistor;
[0022] One end of the second resistor is connected to the first connection point, and the other end of the second resistor is connected to one end of the fifth resistor to form a second voltage divider connection point. The other end of the fifth resistor is grounded.
[0023] The two ends of the second resistor are connected to the switching unit.
[0024] More preferably, the second control loop also includes a third capacitor;
[0025] One end of the third capacitor is connected to the first end of the second switching transistor, and the other end of the third capacitor is connected to the second end of the second switching transistor.
[0026] The third capacitor is connected in parallel with the second resistor.
[0027] More preferably, the switching unit includes a first switching transistor;
[0028] The control terminal of the first switching transistor is connected to the second voltage divider connection point, the first end of the first switching transistor is connected to the first connection point, and the second end of the first switching transistor is connected to the input capacitor.
[0029] Embodiments of this application also provide a hot-plug system, including an electrical device and the aforementioned hot-plug circuit;
[0030] The input capacitor of the hot-swappable circuit is connected to the electrical equipment.
[0031] This application has the following beneficial effects:
[0032] By adding a short pin to the first plug-in, when the first and second plug-ins are connected, the long pin connects to the second plug-in first, followed by the short pin. The long pin connects the control circuit first, but keeps the switching unit in the off state to avoid generating an excessive instantaneous current by immediately connecting the input capacitor. The switching unit is then turned on after the short pin connects. This is equivalent to the first and second plug-ins being connected without power before being powered on, thus converting hot-plugging into non-hot-plugging, effectively suppressing the instantaneous large current and eliminating the problem of sparking of the plug-in contacts during hot-plugging. Attached Figure Description
[0033] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0034] Figure 1 This is a schematic diagram of the hot-plug structure described in the background section of this application;
[0035] Figure 2 This is a schematic diagram of the live insertion and removal current as described in the background section of this application;
[0036] Figure 3 This is a schematic diagram of the input current for hot-plugging as described in Embodiment 1 of this application;
[0037] Figure 4 This is a schematic diagram of the circuit structure of the hot-plugging circuit described in Embodiment 1 of this application;
[0038] Figure 5 This is a schematic diagram of the circuit structure of the input and output terminals of the first and second control loops described in Embodiment 1 of this application;
[0039] Figure 6 This is a schematic diagram of the circuit structure of the first control loop described in Embodiment 1 of this application;
[0040] Figure 7 This is a schematic diagram of the circuit structure of the two voltage divider circuits in Embodiment 1 of this application;
[0041] Figure 8 This is a schematic diagram of the circuit structure of the hot-plug system described in Embodiment 2 of this application;
[0042] Explanation of key component symbols:
[0043] 100. Hot-swappable circuit; 10. First plug-in; 20. Second plug-in; 30. Control circuit; 40. Switching unit; 50. Input capacitor; 11. Long pin; 12. Short pin; 21. Long pin end; 22. Short pin end; 31. First control circuit; 32. Second control circuit; 3101. Input terminal of the first control circuit; 3102. Output terminal of the first control circuit; 3201. Input terminal of the second control circuit; 3202. Output terminal of the second control circuit; 311. First switch control circuit; 312. Second switch control circuit; 3111. First input terminal of the first switch control circuit; 3121. Second switch control circuit 3122, the input terminal of the first switch control circuit; 3112, the second input terminal of the first switch control circuit; 3113, the output terminal of the first switch control circuit; R1, the first resistor; Q2, the second switch transistor; Q4, the fourth switch transistor; L1, the first connection point; Q3, the third switch transistor; U1, the first voltage divider circuit; R6, the sixth resistor; R7, the seventh resistor; L2, the first voltage divider connection point; U2, the second voltage divider circuit; R2, the second resistor; R5, the fifth resistor; L3, the second voltage divider connection point; C3, the third capacitor; Q1, the first switch transistor; 200, electrical equipment; 300, power supply; 400, hot-swappable system. Detailed Implementation
[0044] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.
[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0046] Example 1
[0047] Embodiment 1 of this application provides a hot-swappable circuit 100, wherein hot-swappable refers to the insertion and removal of a device without disconnecting the power supply.
[0048] Furthermore, the hot-swappable circuit 100 includes: a first plug-in 10 and a second plug-in 20 that are mutually connected, a control circuit 30, a switching unit 40, and an input capacitor 50.
[0049] Specifically, see Figure 4 and Figure 8 The switching unit 40 is connected between the control circuit 30 and the input capacitor 50. In this embodiment, the input capacitor 50 is... Figure 4 A capacitor-type energy storage device consisting of the first capacitor C1 and the second capacitor C2 connected in parallel.
[0050] The first plug-in 10 is connected to the power supply, and the second plug-in 20 is connected to the control circuit 30. The first plug-in 10 and the second plug-in 20 are plugged in and out. When the first plug-in 10 and the second plug-in 20 are plugged in, the power supply charges the input capacitor 50. When the first plug-in 10 and the second plug-in 20 are disconnected, the connection between the power supply and the input capacitor 50 is broken.
[0051] The first plug-in 10 and the second plug-in 20 are used to connect and introduce current from the power supply 300 into the electrical device. Specifically, the first plug-in 10 includes a positive long pin 11 and an additional short pin 12, and the short pin 12 is also positive. It can be understood that the long pin 11 is the original positive power terminal of the first plug-in 10, and the short pin 12 is the power terminal added to the first plug-in 10. The long pin 11 and the short pin 12 are electrically connected, that is, both the long pin 11 and the short pin 12 are connected to the positive power terminal of the first plug-in 10.
[0052] Long pin 11 and short pin 12 are provided in the first plug-in 10 for insertion and removal with the second plug-in 20. When the first plug-in 10 and the second plug-in 20 are plugged in, the long pin 11 is connected to the second plug-in 20 first, and the short pin 12 is connected to the second plug-in 20 later. Only after the long pin 11 and the short pin 12 are inserted into the second plug-in 20 in sequence and the long pin 11 and the short pin 12 are stably connected can the input capacitor 50 be charged, thereby supplying power to the electrical equipment 200.
[0053] Control loop 30 is used to control the on / off state of switching unit 40 based on the power supply status connected to its own circuit. See also Figure 4The short pin 12 is an additional component, and the design requires that the length of the short pin 12 be shorter than the length of the long pin 11. During the insertion process of the first plug-in 10 and the second plug-in 20, the long pin 11, due to its longer length, will make electrical contact with the second plug-in 20 first, introducing the current from the power supply 300 into the second plug-in 20. The control circuit 30 connected to the second plug-in 20 starts working after the power supply 300 is connected. The control circuit 30 will control the switching unit 40 to be in the off state. Since the switching unit 40 is in the off state, the current from the power supply 300 cannot be introduced into the input capacitor 50 temporarily, and the input capacitor 50 cannot be charged. After the long pin 10 makes electrical contact with the second plug-in 20, the short pin 12 will make electrical contact with the second plug-in 20 a step later due to its shorter length. At this time, the control circuit 30 has an additional power input terminal. Therefore, under the drive of the dual power supply, the working state of the control circuit changes, thereby controlling the switching unit 40 to be in the conducting state, switching the switching unit 40 from the off state to the conducting state, and power is introduced into the input capacitor 50, and the input capacitor 50 begins to charge.
[0054] It should be noted that this application does not describe the grounding terminal of the first plug-in 10 and the grounding terminal of the second plug-in 20 in detail. (Refer to...) Figure 4 It can be understood that when the first plug-in 10 and the second plug-in 20 are plugged into each other (more specifically, when the long pin 11 is in electrical contact with the second plug-in 20), the corresponding two grounding terminals are electrically connected or in contact with each other to achieve a common ground.
[0055] Therefore, in this embodiment, by adding a short pin 12 to the first plug-in 10, when the first plug-in 10 and the second plug-in 20 are plugged in, the long pin 11 is connected to the second plug-in 20 first, and the short pin 12 is connected to the second plug-in 20 afterward. The long pin 11 first connects the control circuit 30, but keeps the switching unit 40 in the off state to avoid generating an excessive instantaneous large current when the input capacitor 50 is connected at the first moment. After the short pin 12 is connected, the switching unit 40 is controlled to conduct. This is equivalent to the first plug-in 10 and the second plug-in 20 being connected and stable without power before being powered on, thereby converting hot-plugging into non-hot-plugging, thus effectively suppressing the instantaneous large current and eliminating the problem of sparking of the plug-in spring during hot-plugging.
[0056] Furthermore, when the first plug-in 10 is disconnected from the second plug-in 20, the short pin 12 disconnects from the second plug-in 20 first. At this time, the input power supply 300 of the control circuit 30 is only the power supply 300 introduced when the long pin 11 is inserted into the second plug-in 20. The control circuit 30 will control the switching unit 40 to open, thereby disconnecting the power supply 300 to the input capacitor 50, achieving rapid power-off. Afterwards, the long pin 11 disconnects from the second plug-in 20. Since there is no power supply 300 to drive the control circuit 30, it no longer works, and the switching unit 40 remains in the open state.
[0057] In one embodiment, the second plug-in 20 includes a long pin end 21 and a short pin end 22. The long pin end 21 is adapted to mate with the long pin 11 of the first plug-in 10, and the short pin end 22 is adapted to mate with the short pin 12 of the first plug-in 10. Both the long pin end 21 and the short pin end 22 are connected to the control circuit 30. When the first plug-in 10 and the second plug-in 20 are plugged in, the long pin 11 of the first plug-in 10 first makes electrical contact with the long pin end 21 of the second plug-in 20, and then the positive long pin 11 connects the power supply 300 to the control circuit 30; then the short pin 12 of the first plug-in 10 makes contact with the short pin end 22 of the second plug-in 20, and then the same positive short pin 12 connects the power supply 300 to the control circuit 30. The long pin end 21 and the short pin end 22 are energized sequentially, thereby triggering different control states of the control circuit 30 sequentially.
[0058] In one embodiment, see Figure 5 The control loop 30 includes a first control loop 31 and a second control loop 32. The input terminal of the first control loop 31 is connected to the second plug-in 20, the output terminal of the first control loop 31 is connected to the input terminal of the second control loop 32, and the output terminal of the second control loop 32 is connected to the switching unit 40. The first control loop 31 controls the conduction state of the second control loop 32 according to the insertion state of the first plug-in 10 and the second plug-in 20.
[0059] See Figure 4 and Figure 5 Specifically, the end of the first control loop 31 connected to the second plug-in 20 is the input terminal 3101 of the first control loop, and the end of the first control loop 31 connected to the second control loop 32 is the output terminal 3102 of the first control loop. The end of the second control loop 32 connected to the first control loop 31 is the input terminal 3201 of the second control loop, and the end of the second control loop 32 connected to the switching unit 40 is the output terminal 3202 of the second control loop.
[0060] When the long pin 11 of the first plug-in 10 is inserted into the long pin end 21 of the second plug-in 20, and the short pin 12 of the first plug-in 10 has not yet been inserted into the short pin end 22 of the second plug-in 20, the first control circuit 31 causes the second control circuit 32 to be in an open state. The open state of the second control circuit 32 causes the switching unit 40 to also be in an open state. When the short pin 12 of the first plug-in 10 is inserted into the short pin end 22 of the second plug-in 20, the first control circuit 31 causes the second control circuit 32 to be in a conducting state. The conducting state of the second control circuit 32 controls the switching unit 40 to conduct, thereby charging the input capacitor 50.
[0061] Correspondingly, the input terminal of the second control loop 32 is connected to the output terminal of the first control loop 31, and the output terminal of the second control loop 32 is connected to the switching unit 40. The control state of the second control loop 32 is affected by the first control loop 31, and the control state of the first control loop 31 is affected by the insertion state of the first plug-in 10 and the second plug-in 20. When the long pin 11 is inserted into the short pin 12 first, the second control loop 32 maintains its original open state, thereby keeping the switching unit 40 open as well. When the short pin 12 is then inserted into the short pin end 22, the second control loop 32 is turned on, causing the switching unit 40 to switch to the on state, thereby charging the input capacitor 50.
[0062] When the first plug-in 10 and the second plug-in 20 are energized, the current flows into the first control circuit 31 from the input terminal 3101 of the first control circuit, flows out through the output terminal 3102 of the first control circuit, flows into the second control circuit 32 through the input terminal 3201 of the second control circuit, and then flows out through the output terminal 3202 of the second control circuit to the switching unit 40.
[0063] In one embodiment, see Figure 6 The first control loop 31 includes a first switch control circuit 311 and a second switch control circuit 312.
[0064] The first input terminal of the first switch control circuit 311 is connected to the long needle end 21, the input terminal of the second switch control circuit 312 is connected to the short needle end 22, the output terminal of the second switch control circuit 312 is also connected to the second input terminal of the first switch control circuit 311, and the output terminal of the first switch control circuit 311 is connected to the input terminal of the second control circuit 32.
[0065] The second switch control circuit 312 is used to control the working state of the first switch control circuit 311.
[0066] The end of the first switch control circuit 311 connected to the long needle end 21 is designated as the first input terminal 3111 of the first control switch control circuit 311, the end of the first switch control circuit 311 connected to the second switch circuit is designated as the second input terminal 3112 of the first switch control circuit 311, and the end of the first switch control circuit 311 connected to the second control loop 32 is designated as the output terminal 3113 of the first switch control circuit.
[0067] The end of the second switch control circuit 312 connected to the short needle end 22 is the input terminal 3121 of the second switch control circuit, and the end of the second switch control circuit 312 connected to the first switch control circuit 311 is the output terminal 3122 of the second switch control circuit.
[0068] In this embodiment, the second switch control circuit 312 is used to control the operating state of the first switch control circuit 311, and the first switch control circuit also affects the operating state of the second control circuit 32. Specifically, when the first plug-in 10 and the second plug-in 20 are energized, the long pin 11 is first connected to the long pin end 21. At this time, current flows in from the first input terminal 3111 of the first switch control circuit 311 and forms a loop by grounding. The continuity state of the first switch control circuit 311 affects the second control circuit 32, causing the second control circuit 32 to be in an open state (no current flows through it). When the short pin 12 is connected to the short pin end 22, current flows in from the input terminal 3121 of the second switch control circuit 312. After being powered on, the second switch control circuit 312 switches the working state of the first switch control circuit 311 (switches to the off state), thereby switching the state of the second control circuit 32 to the on state, so that the current flowing in from the second plug-in 20 flows through the second control circuit 32. After the second control circuit 32 is turned on, it also switches the control state of the switch unit 40 from off to on, thereby charging the input capacitor 50.
[0069] In one embodiment, the first switch control circuit 311 includes a first resistor R1, a second switch Q2, and a fourth switch Q4. One end of the first resistor R1 is connected to the long pin end 21 to form a first connection point L1, and the other end of the first resistor R1 is connected to the control terminal of the fourth switch Q4. The first terminal of the fourth switch Q4 is connected to the control terminal of the second switch Q2, and the second terminal of the fourth switch Q4 is grounded. The first terminal of the second switch Q2 is connected to the first connection point L1, and the second terminal of the second switch Q2 is connected to the input terminal of the second control loop 32.
[0070] In this configuration, the fourth switch Q4 is connected between the long needle end 21 and the ground terminal; the first resistor R1 is connected between the long needle end 21 and the fourth switch Q4; and the second switch Q2 is connected between the fourth switch Q4 and the second control circuit 32, and further connected between the second switch Q2 and the first connection point L1. This is equivalent to the second switch Q2 and the second control circuit 32 being connected in parallel at the first connection point L1.
[0071] When the long pin 11 makes electrical contact with the long pin end 21, the fourth switch Q4, connected between the long pin end 21 and the ground terminal, is turned on. The turn on of the fourth switch Q4 then controls the turn on of the second switch Q2. For the second switch Q2 and the second control circuit 32 connected in parallel at the first connection point L1, the impedance of the second switch Q2 in the turned-on state is small and negligible. However, the impedance of the second control circuit 32 is large, and current flows through the second switch Q2 and the fourth switch Q4 before entering the ground terminal, causing the second control circuit 32 to be in a near-current-free state. When the short pin 12 is inserted into the short pin end 22, the current does not pass through the fourth switch Q4, causing the fourth switch Q4 to be in the off state, which in turn causes the second switch Q2 to be in the off state. This allows current to flow into the second control circuit 32, thus switching the operating state of the second control circuit 32.
[0072] The second switch Q2 can be a current-controlled NPN or PNP transistor, or a voltage-controlled N-channel or P-channel MOSFET. In this embodiment, the second switch Q2 is a transistor, with its emitter connected to the second plug-in 20 and its base connected to the third resistor R3. Since the emitter of the fourth switch Q4 is already conducting, the current starts from the long needle end 21, passes sequentially through the emitter and base of the second switch Q2, the third resistor, the collector of the fourth switch Q4, the base of the fourth switch Q4, and the emitter of the fourth switch Q4 before reaching ground.
[0073] Furthermore, the fourth switch Q4 can also be a current-controlled NPN or PNP transistor, or a voltage-controlled N-channel or P-channel MOSFET. In this embodiment, the fourth switch Q4 is a transistor, the fourth resistor R4 is connected to the base of the fourth switch Q4, the collector of the fourth switch Q4 is connected to the base of the second switch Q2, and the emitter of the fourth switch Q4 is connected to ground. Current flows into the base of the fourth switch Q4, flows out through the emitter to ground. Since a transistor is a current-conducting device, and there is sufficient current injected into the base from the emitter, the fourth switch Q4 is turned on, and consequently, the collector of the fourth switch Q4 is also turned on.
[0074] In one embodiment, see Figure 7The second switch control circuit 312 includes a third switch transistor Q3 and a first voltage divider circuit U1. The first voltage divider circuit U1 includes a sixth resistor R6 and a seventh resistor R7. One end of the seventh resistor R7 is connected to the short pin end 22, and the other end of the seventh resistor R7 is connected to one end of the sixth resistor R6 to form a first voltage divider connection point L2. The other end of the sixth resistor R6 is grounded. The control terminal of the third switch transistor Q3 is connected to the first voltage divider connection point L2. The first end of the third switch transistor Q3 is connected to the other end of the first resistor R1, and the second end of the third switch transistor Q3 is grounded. The first end of the third switch transistor Q3 and the control terminal of the fourth switch transistor Q4 are connected in parallel with the first resistor R1.
[0075] When the long pin 11 is inserted into the long pin end 21 first, the third switch Q3 remains in the off state. When the short pin 12 is inserted into the short pin end 22, the first voltage divider circuit U1 causes the first voltage divider connection point L2 to reach the working threshold, causing the third switch Q3 to switch from the off state to the on state. After the third switch Q3 is turned on, the fourth switch Q4 switches to the off state, which in turn causes the second switch Q2 to also switch to the off state. Current flows into the second control circuit 32, changing the working state of the second control circuit 32 to switch the switching unit 40 to the on state, allowing current to flow into the input capacitor 50 for charging.
[0076] The third switch Q3 can be a current-controlled NPN or PNP transistor, or a voltage-controlled N-channel or P-channel MOSFET. In this embodiment, the third switch Q3 is an N-channel MOSFET. The gate of the third switch Q3 is connected to the first voltage divider connection point L2 between the seventh resistor R7 and the sixth resistor R6. The drain of the third switch Q3 is connected to one end of the other end of the first resistor R1, and the source of the third switch Q3 is grounded. When the short pin 22 is energized, the sixth resistor R6 and the seventh resistor R7 act as a voltage divider, and the voltage at the gate of the third switch Q3 reaches the conduction threshold, thus turning on the third switch Q3, thereby connecting the drain and source of the third switch Q3. The current starts from the long needle end 21, first passing through the first resistor R1, then through the fourth switch Q4 and the third switch Q3 connected in parallel. Because the impedance of the fourth resistor and the fourth switch Q4 is relatively high, and the source of the third switch Q3 is directly grounded with a lower impedance than the fourth switch Q4, the current preferentially chooses to flow through the path of the third switch Q3. Consequently, the emitter of the fourth switch Q4 does not receive enough current into its base, thus the fourth switch Q4 is turned off. Since the fourth switch Q4 is turned off, the second switch Q2, which is connected in series with the fourth switch Q4, is also turned off.
[0077] In one embodiment, see Figure 7The second control loop 32 includes a second voltage divider circuit U2. The second voltage divider circuit U2 includes a second resistor R2 and a fifth resistor R5. One end of the second resistor R2 is connected to the first connection point L1, and the other end of the second resistor R2 is connected to one end of the fifth resistor R5 to form the second voltage divider connection point L3. The other end of the fifth resistor R5 is connected to the ground terminal. Furthermore, both ends of the second resistor R2 are connected to the switching unit 40.
[0078] As described above, when the long pin 11 is connected to the long pin end 21, no current flows through the second control circuit 32. Therefore, the voltage at the second voltage divider connection point L3 in the second voltage divider circuit U2 cannot reach the operating threshold voltage of the switching unit 40, so the switching unit 40 remains in the open state. When the short pin 12 is connected to the short pin end 22, current flows through the second control circuit 32, and the second voltage divider connection point L3 in the second voltage divider circuit U2 reaches the operating threshold voltage, causing the switching unit 40 to switch to the conducting state, thereby charging the input capacitor 50.
[0079] Based on this, the second control loop 32 also includes a third capacitor C3. One end of the third capacitor C3 is connected to the first end of the second switch Q2, and the other end of the third capacitor C3 is connected to the second end of the second switch Q2. The third capacitor C3 is connected in parallel with the second resistor R2.
[0080] When the long pin 11 is connected to the long pin end 21, the third capacitor C3 does not receive current for charging and is considered a closed circuit in the loop. This prevents the voltage at the second voltage divider connection point L3 from reaching the operating threshold, thus keeping the switch unit 40 in the open state. When the short pin 12 is connected to the short pin end 22, the third capacitor C3 charges slowly. After charging, the third capacitor C3 is considered an open circuit in the loop, causing the voltage at the second voltage divider connection point L3 to reach the operating threshold, thus switching the switch unit 40 to the on state.
[0081] From the moment short pin 12 is inserted into short pin end 22 until the third capacitor C3 is fully charged, causing the switching unit 40 to conduct, the input capacitor 50 only begins charging after the third capacitor C3 is fully charged, thus generating a large instantaneous current. However, when short pin 12 is inserted into short pin end 22, the first plug-in 10 and the second plug-in 20 have already completed their connection. The time of the large instantaneous current is later than the time when the first plug-in 10 and the second plug-in 20 complete their connection, thus transforming the hot-plugging of the first plug-in 10 and the second plug-in 20 into a non-hot-plugging process, thereby greatly suppressing the degree of the large instantaneous current. See [link to relevant documentation]. Figure 3 The instantaneous current was suppressed to a level of 6A, eliminating the electric sparks generated by the instantaneous large current during hot plugging and unplugging.
[0082] More preferably, the switching unit 40 includes a first switching transistor Q1. The control terminal of the first switching transistor Q1 is connected to the second voltage divider connection point L3, the first terminal of the first switching transistor Q1 is connected to the first connection point L1, and the second terminal of the first switching transistor Q1 is connected to the input capacitor 50.
[0083] Specifically, when the voltage at the second voltage divider connection point L3 reaches the operating threshold of the first switch Q1, the first switch Q1 switches to the on state; when the voltage at the second voltage divider connection point L3 is lower than the operating threshold of the first switch Q1, the first switch Q1 switches to the off state. When the first switch Q1 is in the on state, the power supply 300 charges the input capacitor 50. When the first switch Q1 is in the off state, the power supply 300 stops charging the capacitor.
[0084] When the first plug-in 10 and the second plug-in 20 are disconnected, the short pin 12 separates from the short pin end 22 first, and the long pin 11 separates from the long pin end 21 later. When the short pin 12 separates from the short pin end 22 first, but the long pin 11 does not separate from the long pin end 22, the voltage at the first voltage divider connection point L2 quickly drops below the operating threshold, causing the third switch Q3 to quickly turn off. This causes the fourth switch Q4 and the second switch Q2 to quickly switch to the on state, allowing the charge of the third capacitor C3 to quickly discharge through the discharge path formed by the fourth switch Q4 and the second switch Q2. This causes the voltage at the second voltage divider connection point L3 to quickly drop below the operating threshold, causing the first switch Q1 to quickly switch to the off state, stopping the charging of the input capacitor 50. When the long pin 11 separates from the long pin end 21 later, the fourth switch Q4 and the second switch Q2 also quickly switch to the off state.
[0085] In summary, when the first plug-in 10 and the second plug-in 20 are energized, the circuit primarily functions as a soft-start mechanism. This means that the charging of the input capacitor 50 occurs later than the insertion of the first plug-in 10 and the second plug-in 20. Consequently, the instantaneous high current generated during the charging of the input capacitor 50 occurs immediately after the first plug-in 10 and the second plug-in 20 are fully inserted, significantly suppressing the peak current and eliminating electrical sparks during insertion. Conversely, when the first plug-in 10 and the second plug-in 20 are disconnected, the circuit provides rapid disconnection, making it suitable for scenarios requiring quick insertion and removal.
[0086] The first switching transistor Q1 can be a current-controlled NPN or PNP transistor, or a voltage-controlled N-channel or P-channel MOSFET. In this embodiment, the first switching transistor Q1 is a P-channel MOSFET. The gate of the first switching transistor Q1 is connected to the second voltage divider connection point L3, the source of the first switching transistor Q1 is connected to the first connection point L1, and the drain of the first switching transistor Q1 is connected to one end of the input capacitor 50.
[0087] Example 2
[0088] See Figure 8 This application provides a live-plug system 400 in embodiment two, including a live-plug circuit 100 as described in embodiment one. One end of the live-plug circuit 100 is connected to a power supply 300, and the other end is connected to a device 200. Specifically, the input capacitor 50 of the live-plug circuit 100 is electrically connected to the device 200. The device 200 can be any device that requires live-plugging, such as portable electronic devices, medical devices, power tools, portable communication devices, computer devices, or consumer electronic devices. In one embodiment, the device 200 can be an ultrasound device used in the medical field, which uses high-frequency sound waves to penetrate human tissue and reflect back to form images for observing internal structures.
[0089] It should be noted that since the hot-plug circuit 100 in the hot-plug system shown in Embodiment 2 of this application is exactly the same as the hot-plug circuit 100 in Embodiment 1, the beneficial effects of the hot-plug circuit 100 in Embodiment 2 are also exactly the same as those in Embodiment 1, and will not be repeated here.
[0090] The embodiments described above are merely examples of several implementations of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the scope of protection of this application.
Claims
1. A hot-swappable circuit, characterized in that, The hot-swappable circuit includes: a first plug-in and a second plug-in that are mated together, a control circuit, a switching unit, and an input capacitor; The first plug-in includes a long pin and a short pin with positive polarity, and the long pin and the short pin are electrically connected; The second plug-in is connected to the input terminal of the control loop, the output terminal of the control loop is connected to the switching unit, and the switching unit is also connected to the input capacitor; When the first plug-in and the second plug-in are connected, the long pin is inserted into the second plug-in first, and the control circuit controls the switching unit to be in the off state; the short pin is then inserted into the second plug-in, and the control circuit controls the switching unit to be in the on state to charge the input capacitor.
2. The hot-swappable circuit according to claim 1, characterized in that, The second insert includes a long needle end and a short needle end; When the first plug-in and the second plug-in are connected, the long pin first makes electrical contact with the long pin end, and the short pin then makes electrical contact with the short pin end.
3. A hot-swappable circuit according to claim 2, characterized in that, The control circuit includes a first control circuit and a second control circuit. The input terminal of the first control circuit is connected to the second plug-in, the output terminal of the first control circuit is connected to the input terminal of the second control circuit, and the output terminal of the second control circuit is connected to the switching unit.
4. A hot-swappable circuit according to claim 3, characterized in that, The first control loop includes a first switch control circuit and a second switch control circuit; The first input terminal of the first switch control circuit is connected to the long needle end, the input terminal of the second switch control circuit is connected to the short needle end, the output terminal of the second switch control circuit is also connected to the second input terminal of the first switch control circuit, and the output terminal of the first switch control circuit is connected to the input terminal of the second control loop. The second switch control circuit is used to control the operating state of the first switch control circuit.
5. A hot-swappable circuit according to claim 4, characterized in that, The first switch control circuit includes a first resistor, a second switch transistor, and a fourth switch transistor; One end of the first resistor is connected to the end of the long needle to form a first connection point, the other end of the first resistor is connected to the control terminal of the fourth switch, the first end of the fourth switch is connected to the control terminal of the second switch, and the second end of the fourth switch is grounded. The first end of the second switch is connected to the first connection point, and the second end of the second switch is connected to the input terminal of the second control loop.
6. A hot-swappable circuit according to claim 5, characterized in that, The second switch control circuit includes a third switch transistor and a first voltage divider circuit; the first voltage divider circuit includes a sixth resistor and a seventh resistor; One end of the seventh resistor is connected to the short needle end, and the other end of the seventh resistor is connected to one end of the sixth resistor to form a first voltage divider connection point. The other end of the sixth resistor is grounded. The control terminal of the third switch is connected to the first voltage divider connection point, the first end of the third switch is connected to the other end of the first resistor, and the second end of the third switch is grounded.
7. A hot-swappable circuit according to claim 5, characterized in that, The second control loop includes a second voltage divider circuit, which includes a second resistor and a fifth resistor; One end of the second resistor is connected to the first connection point, and the other end of the second resistor is connected to one end of the fifth resistor to form a second voltage divider connection point. The other end of the fifth resistor is grounded. The two ends of the second resistor are connected to the switching unit.
8. A hot-swappable circuit according to claim 7, characterized in that, The second control loop also includes a third capacitor; One end of the third capacitor is connected to the first end of the second switching transistor, and the other end of the third capacitor is connected to the second end of the second switching transistor. The third capacitor is connected in parallel with the second resistor.
9. A hot-swappable circuit according to claim 7, characterized in that, The switching unit includes a first switching transistor; The control terminal of the first switching transistor is connected to the second voltage divider connection point, the first end of the first switching transistor is connected to the first connection point, and the second end of the first switching transistor is connected to the input capacitor.
10. A hot-plugging system, characterized in that, Includes electrical equipment and a hot-plug circuit as described in any one of claims 1-9; The input capacitor of the hot-swappable circuit is connected to the electrical equipment.