Rapid discharging circuit and vehicle-mounted domain control machine
By designing a fast discharge circuit in the vehicle domain control system and using the first switching circuit to control the discharge of the discharge power supply, the problem of disordered timing of the rapid start-up after shutdown is solved, and the reliability and service life of the system are improved.
Patent Information
- Application Number
- CN202420606967.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-26
- Publication Date
- 2025-02-21
- Estimated Expiration
- 2034-03-26
AI Technical Summary
In the scenario of quickly turning on the computer after shutdown, the on-board domain control system is prone to timing disorders, resulting in crashes or failure of functions.
A fast discharge circuit is designed, including a discharge power supply, a discharge resistor and a first switching circuit. By controlling the first switching circuit, rapid discharge after shutdown is achieved to ensure normal timing of the control chip.
It realizes the normality of the fast start-up timing after shutdown, avoids failure caused by long-term operation of the discharge resistor, and improves the reliability and service life of the system.
Smart Images
Figure CN222515183U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of automotive electronic technology, and in particular to a fast discharge circuit and a vehicle-mounted domain controller. Background Art
[0002] In-vehicle domain controllers are mostly used in scenarios where they are turned off and then turned on quickly. Currently, there are more and more high-power consumption chips and system-level chips in domain controllers. Therefore, larger-capacity capacitors are needed in circuit design to store energy and filter to keep the voltage stable.
[0003] However, in the scenario of quickly restarting after shutting down, it is easy for the voltage to drop slowly after shutdown. When the power is quickly restarted, the voltage has not dropped to 0V, and it is restarted again, which is easy to cause timing disorder, and then lead to events such as freeze or function failure. Utility Model Content
[0004] The purpose of the utility model is to provide a fast discharge circuit and a vehicle-mounted domain controller, which are used to achieve fast discharge after shutdown, and in the application scenario of fast startup after shutdown, ensure the normal timing of the control chip.
[0005] In order to solve the above technical problems, the present application provides a fast discharge circuit, including: a discharge power supply; a discharge resistor, connecting the discharge power supply and a ground line; a first switch circuit, arranged between the discharge resistor and the ground line, for controlling the on-off of the discharge power supply and the ground line, so as to discharge the discharge power supply during the discharge stage.
[0006] Preferably, the fast discharge circuit further includes a control circuit, which is connected to the control end of the first switch circuit and is used to control the first switch circuit to be turned on during the discharge phase and to control the first switch circuit to be turned off during the power-on phase.
[0007] Preferably, the first switching circuit includes an NMOS tube, the gate of the NMOS tube is connected to the control circuit, the source is connected to the ground line, and the drain is connected to the discharge power supply; wherein the control circuit outputs a high level in the discharge stage and outputs a low level in the power-on stage.
[0008] Preferably, the first switch circuit further includes a capacitor, a first plate of the capacitor is connected to the gate of the NMOS tube, and a second plate of the capacitor is connected to the ground line and the source of the NMOS tube to maintain the voltage of the gate of the NMOS tube.
[0009] Preferably, the fast discharge circuit further comprises a first diode, the anode of the first diode is connected to the control circuit, and the cathode of the first diode is connected to the gate of the NMOS tube to maintain the gate voltage of the NMOS tube.
[0010] Preferably, the control circuit comprises a second switch circuit, one end of the second switch circuit is connected to a high potential power supply, and the other end is connected to a control end of the first switch circuit, so as to transmit a high potential voltage to the control end of the first switch circuit during a discharge phase.
[0011] Preferably, the control circuit also includes a switch control signal source, which is connected to the control end of the second switch circuit and is used to control the on and off of the second switch circuit; wherein the second switch circuit includes a PMOS tube, the switch control signal source is connected to the gate of the PMOS tube, and outputs a low level in the discharge stage to control the source and drain of the PMOS tube to be turned on in the discharge stage, so as to transmit the high potential voltage of the high potential power supply to the control end of the first switch circuit.
[0012] Preferably, the control circuit also includes a first resistor and a second resistor, one end of the first resistor is connected to the high potential power supply and the source of the PMOS tube, and the other end is connected to the gate of the PMOS tube; one end of the second resistor is connected to the gate of the PMOS tube, and the other end is connected to the switch control signal source; wherein the resistance of the first resistor is greater than the resistance of the second resistor, so that the voltage difference between the gate and the source of the PMOS tube can reach the threshold voltage, thereby ensuring the turning on of the PMOS tube.
[0013] Preferably, the control circuit also includes a second diode, the anode of the second diode is connected to the other end of the second resistor, and the cathode is connected to the power-on / off control signal source to prevent the high level of the power-on / off control signal source from being transmitted to the high-potential power supply during the power-on stage, thereby burning out the high-potential power supply.
[0014] In order to solve the above technical problems, the present application also provides a vehicle-mounted domain controller, which includes the fast discharge circuit described in any of the above embodiments.
[0015] The beneficial effect of the present application is as follows: by setting a first switching circuit between the discharge power supply and the ground line, the discharge power supply is controlled to discharge by controlling the first switching circuit, so that rapid discharge can be performed under the triggering of a shutdown signal, thereby avoiding the discharge resistor from being in a working state for a long time and causing failure, and is also suitable for the scenario of rapid startup after shutdown. Compared with the prior art, it is necessary to delay for a period of time after receiving the power-on signal before turning on the power supply so that the circuit can be fully discharged before being started again, the present application can achieve immediate shutdown, and after immediately starting up, the first switching circuit can be cut off after a period of discharge, and can also avoid the discharge resistor from being in a long-term working state and causing failure. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0017] Figure 1 This is a structural schematic diagram of an embodiment of a fast discharge circuit of the present application;
[0018] Figure 2 This is a schematic structural diagram of a first specific embodiment of a fast discharge circuit of the present application;
[0019] Figure 3 This is a structural schematic diagram of a second specific embodiment of the fast discharge circuit of the present application;
[0020] Figure 4 This is a schematic structural diagram of a third specific embodiment of a fast discharge circuit of the present application. DETAILED DESCRIPTION
[0021] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0022] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms of "a", "said", and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless otherwise clearly indicated above, and "multiple" generally includes at least two, but does not exclude the inclusion of at least one.
[0023] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.
[0024] It should be understood that the terms "include", "comprises" or any other variations used herein are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, the elements defined by the sentence "includes..." do not exclude the presence of other identical elements in the process, method, article or device that includes the elements.
[0025] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.
[0026] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The presence of the phrase at each location in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.
[0027] The present application is now further described with reference to the accompanying drawings and specific embodiments.
[0028] This application provides a fast discharge circuit, see Figure 1 , Figure 1 FIG. 1 is a schematic diagram of a structure of an embodiment of a fast discharge circuit of the present application. Figure 1 As shown, the fast discharge circuit includes: a discharge power source VDD, a discharge resistor R1 and a first switch circuit 11.
[0029] The discharge power source VDD is connected to the ground line through the discharge resistor R1, and discharges through the discharge resistor R1 to avoid direct discharge and burning of the discharge power source VDD. The discharge resistor R1 can be understood as the resistance of the wiring directly connecting the discharge power source VDD and the ground line, which is not limited here.
[0030] The first switch circuit 11 is arranged between the discharge resistor R1 and the ground line, and is used to control the on / off of the discharge power supply VDD and the ground line, so as to discharge the discharge power supply VDD in the discharge phase. The discharge phase is the beginning phase of the shutdown phase (that is, a period of time after shutdown), and the shutdown phase includes the discharge phase.
[0031] Among them, the fast discharge circuit in the present application is applied to the vehicle-mounted domain control system of the switch. Specifically, in the discharge stage (that is, when shutting down), the discharge resistor R1 and the ground wire are turned on by controlling the first switch circuit 11 to form a path, so as to discharge the discharge voltage VDD. In addition, in the startup stage, the first switch circuit 11 is controlled to be disconnected, so that the discharge resistor R1 and the ground wire are disconnected, so that the discharge resistor R1 can be in a non-working state during the startup period or during the normal operation of the discharge power supply VDD, thereby avoiding the problem that the discharge resistor R1 is in a working state for a long time and easily causes the failure of the resistor, thereby improving the service life of the discharge resistor R1. Compared with the solution in the prior art that the discharge power supply VDD is directly grounded through the discharge resistor R1, in the startup stage, during the normal operation of the discharge power supply VDD, since the discharge power supply VDD is always a high potential voltage, current continues to flow through the resistor, and the resistor has long-term power consumption, which is easy to cause the failure of the resistor, greatly reducing the service life of the resistor, and it is also easy to cause the resistor to overheat and burn out.
[0032] For further information, see Figure 2 , Figure 2 This is a schematic diagram of the structure of the first specific embodiment of the fast discharge circuit of the present application. Figure 2 As shown, the fast discharge circuit also includes a control circuit 12, which is connected to the control end of the first switch circuit 11 and is used to control the first switch circuit 11 to be turned on during the discharge phase and to control the first switch circuit 11 to be turned off (disconnected) during the startup phase.
[0033] In this specific embodiment, the first switch circuit 11 includes an NMOS transistor Q1. The gate of the NMOS transistor is connected to the control circuit 12, the source is connected to the ground line, and the drain is connected to the discharge power supply VDD. The gate of the NMOS transistor Q1 is turned on under a high-level voltage, and the control circuit 12 outputs a high level in the discharge phase, and outputs a low level or no high-level signal in the power-on phase, so that it maintains a low-level signal, thereby making it non-conductive.
[0034] In other embodiments, other control circuits or signals may also be used to control the on and off of the first switch circuit.
[0035] Furthermore, the first switch circuit 11 further includes a capacitor C, a first plate of the capacitor C is connected to the gate of the NMOS tube Q1, and a second plate of the capacitor C is connected to the ground wire and the source of the NMOS tube Q1 to maintain the voltage of the gate of the NMOS tube Q1, so as to ensure that the NMOS tube Q1 is in a conducting state within a certain period of time. Among them, the two-stage plates of the capacitor C are respectively connected to the gate and the source of the NMOS tube Q1 for conduction, and the voltage value of the capacitor C is greater than the threshold voltage (that is, the turn-on voltage) of the NMOS tube Q1, so that the NMOS tube Q1 can be in a conducting state. After a certain period of time, under the natural leakage of the capacitor C, the voltage of the gate of the NMOS tube Q1 will slowly decrease until the NMOS tube Q1 is cut off, at which time, the discharge ends.
[0036] Furthermore, the first switch circuit 11 further includes a first diode D1, the anode of the first diode D1 is connected to the control circuit 12, and the cathode is connected to the gate of the NMOS tube Q1, so as to prevent the gate voltage of the NMOS tube Q1 from leaking through the control circuit 12, thereby maintaining / maintaining the gate voltage of the NMOS tube Q1. In this specific embodiment, the high-level signal output by the control circuit 12 can be a slowly decreasing voltage, and in the case of throttling of the first diode D1, even if the level signal of the control circuit 12 is unstable, it does not affect the conduction of the first switch circuit 11.
[0037] In other embodiments, the capacitor C and the first diode D1 may not be provided, and only one or two of them may be provided, which is not limited here.
[0038] For further information, see Figure 3 , Figure 3 FIG. 1 is a schematic diagram of the structure of the second specific embodiment of the fast discharge circuit of the present application. Figure 3 As shown, the control circuit includes a second switch circuit 13, one end of the second switch circuit 13 is connected to the high potential power supply VDD_IN, and the other end is connected to the control end of the first switch circuit 11, so as to transmit a high potential voltage to the control end of the first switch circuit 11 during the discharge stage, so that the first switch circuit 11 is in a conductive state during the discharge stage.
[0039] In a specific embodiment, the control circuit 12 further includes a power-on / off control signal source 14 , which is connected to the control end of the second switch circuit 13 and is used to control the on / off of the second switch.
[0040] See further Figure 4 , Figure 4This is a schematic diagram of the structure of the third specific embodiment of the fast discharge circuit of the present application. Specifically, the second switch circuit 13 includes a PMOS tube Q2. The gate of the PMOS tube Q2 is connected to the switch control signal source 14, the source is connected to the high potential power supply VDD_IN, and the drain is connected to the control end of the first switch circuit 11. Among them, when the voltage difference between the source and the gate of the PMOS tube Q2 is greater than the threshold voltage, the switch control signal source 14 outputs a low level in the discharge stage to control the source and drain of the PMOS tube to be turned on in the discharge stage, so as to transmit the high potential voltage of the high potential power supply of the source to the control end of the first switch circuit 11. In other embodiments, the second switch circuit 13 may also include other switching devices, which are not limited here. It should be noted that the control end of the first switch circuit 11 is the gate of the NMOS tube.
[0041] Furthermore, the control circuit 12 further includes a first resistor R2 and a second resistor R3, one end of the first resistor R2 is connected to the high potential power supply VDD_IN and the source of the PMOS tube Q2, and the other end is connected to the gate of the PMOS tube Q2. The source and the gate of the PMOS tube Q2 form a voltage difference through the resistance voltage division on the first resistor R2. When the voltage difference is greater than the turn-on threshold of the PMOS tube Q2, the PMOS tube Q2 is turned on, thereby inputting a high potential voltage to the control end of the first switch circuit 11. One end of the second resistor R3 is connected to the first resistor R2 and the gate of the PMOS tube Q2, and the other end is connected to the switch control signal source 14, which is used to divide the voltage with the first resistor R2 to prevent the voltage of the high potential power supply VDD_IN from falling entirely on the first resistor R2, causing the first resistor R2 to burn out, and further causing the PMOS tube Q2 to work abnormally. In this embodiment, the resistance value of the first resistor R2 and the resistance value of the second resistor R3 are reasonably selected so that the voltage difference across the first resistor R2 satisfies the conduction threshold of the PMOS tube Q2, so that the voltage difference between the source and the gate of the PMOS tube Q2 can reach the turn-on voltage (that is, the threshold voltage), thereby ensuring that the PMOS tube Q2 can be turned on.
[0042] Furthermore, the control circuit 12 also includes a second diode D2, the anode of the second diode D2 is connected to the other end of the second resistor R3, so as to be connected to the high potential power supply VDD_IN through the second resistor R3 and the first resistor R2; the cathode of the second diode D2 is connected to the power on / off control signal source 14, so as to prevent the high potential voltage of the power on / off control signal source 14 from being transmitted to the high potential power supply VDD_IN during the power-on stage, thereby burning the high potential power supply VDD_IN.
[0043] It should be noted that in the present application, the high potential power supply VDD_IN is the upper power supply of the discharge voltage VDD, and the voltage can be gradually reduced after shutdown, that is, gradually discharged. At the moment of shutdown, the high potential voltage on the high potential power supply VDD_IN is transmitted to the gate of the NMOS tube Q1 through the PMOS tube Q2, and is maintained for a certain time through the first diode Q1 and the capacitor C, thereby continuously discharging the discharge voltage VDD and avoiding incomplete discharge.
[0044] During the power-on phase, the power-on / off control signal source is at a high level. Due to the reverse cutoff effect of the second diode D2, no current flows through the first resistor R2 and the second resistor R3. There is no voltage difference between the first resistor R2, resulting in the Vgs (gate-source voltage) of Q2 not reaching the turn-on threshold. Q2 is in the cut-off state, and the capacitor C cannot be charged by the high-potential power supply VDD_IN. The voltage across the capacitor C is zero. Therefore, the Vgs voltage of Q1 is also zero, and Q1 is in the cut-off state. Therefore, the discharge resistor R1 does not consume current, and there is no fatigue stress during the power-on phase.
[0045] In the shutdown discharge stage, the power on / off control signal source is at a low level, D2 is forward-conducted, resulting in a voltage difference on the resistor R2, and the Vgs of Q2 reaches the conduction threshold. Q2 is turned on, and VDD_IN charges the capacitor C through the first diode D1, so that the Vgs of Q1 reaches the conduction threshold. Q1 is in the on state, and the discharge power supply VDD can be quickly discharged through the discharge resistor R1.
[0046] It should be noted that when the shutdown signal is triggered, the power-on / off control signal output by the power-on / off control signal source is at a low level, Q2 will be turned on immediately, and the charging of capacitor C will be completed. When the MCU inside the domain controller recognizes the shutdown signal and shuts down the high-potential power supply VDD_IN, the voltage on VDD_IN begins to drop rapidly, but because the first diode D1 is in a reverse state, the voltage across capacitor C will not be pulled down, Q1 can still be in the on state and last for a period of time, thereby realizing the rapid discharge function.
[0047] The present application also provides a vehicle-mounted domain controller, wherein the vehicle-mounted domain controller includes the fast discharge circuit described in any of the above embodiments. The vehicle-mounted domain controller can be an MCU, which itself includes a discharge power supply VDD, a high potential power supply VDD_IN, and a control signal source such as a power on / off control signal source. The present application controls multiple MOS tube devices by using its own control signal as a control signal source, thereby realizing the fast discharge function of the power supply.
[0048] The beneficial effects of the present application are: in the power-on state, all devices (Q1, Q2, R1, R2, R3) in the fast discharge circuit are in the off state, mainly because the discharge resistor R1 is not in the working state, thus avoiding the risk of failure caused by the long-term operation of the discharge resistor R1. Second, it can meet the needs of fast discharge application scenarios. In the application scenario of fast startup after shutdown, the charge on the capacitor C will be naturally consumed, and Q1 will be in the cut-off state after a few seconds, and the discharge resistor R1 will not be in the working state for a long time. In the application scenario of fast startup after shutdown, even if Q1 is still in the on state, since Q1 is in the on-state for a short time and the charging voltage of the discharge power supply VDD is large, it will not affect the normal working function of the vehicle-mounted domain controller. Third, in the off state, there is no current consumption, which reduces the static current of the product.
[0049] The above description is only an implementation method of the present application, and does not limit the patent protection scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.
Claims
1. A fast discharge circuit, characterized in that: The fast discharge circuit comprises: Discharge power supply; A discharge resistor, connected to the discharge power supply and a ground wire; A first switch circuit is provided between the discharge resistor and the ground line, and is used to control the on / off connection between the discharge power source and the ground line, so as to discharge the discharge power source in the discharge stage; A control circuit, the control circuit being connected to the control end of the first switch circuit and being used to control the first switch circuit to be turned on during a discharge phase and to control the first switch circuit to be turned off during a power-on phase; A first diode, wherein an anode of the first diode is connected to the control circuit, and a cathode of the first diode is connected to the control end of the first switch circuit, so as to maintain the stability of the voltage at the control end of the first switch circuit.
2. The fast discharge circuit according to claim 1, characterized in that: The first switch circuit includes an NMOS tube, a gate of the NMOS tube is connected to the control circuit, a source is connected to the ground line, and a drain is connected to the discharge power supply; wherein the control circuit outputs a high level in the discharge stage and outputs a low level in the power-on stage.
3. The fast discharge circuit according to claim 2, characterized in that: The first switch circuit also includes a capacitor, a first plate of the capacitor is connected to the gate of the NMOS tube, and a second plate of the capacitor is connected to the ground line and the source of the NMOS tube to maintain the voltage of the gate of the NMOS tube.
4. The fast discharge circuit according to claim 1, characterized in that: The control circuit includes a second switch circuit, one end of which is connected to a high potential power supply, and the other end of which is connected to a control end of the first switch circuit, so as to transmit a high potential voltage to the control end of the first switch circuit during a discharge phase.
5. The fast discharge circuit according to claim 4, characterized in that: The control circuit further includes a power-on / off control signal source, which is connected to the control end of the second switch circuit and is used to control the on / off of the second switch circuit; Among them, the second switching circuit includes a PMOS tube, the switch control signal source is connected to the gate of the PMOS tube, and outputs a low level in the discharge stage, controls the source and drain of the PMOS tube to be turned on in the discharge stage, so as to transmit the high potential voltage of the high potential power supply to the control end of the first switching circuit.
6. The fast discharge circuit according to claim 5, characterized in that: The control circuit also includes a first resistor and a second resistor, one end of the first resistor is connected to the high potential power supply and the source of the PMOS tube, and the other end is connected to the gate of the PMOS tube; one end of the second resistor is connected to the gate of the PMOS tube, and the other end is connected to the switch control signal source; wherein the resistance of the first resistor is greater than the resistance of the second resistor, so that the voltage difference between the gate and the source of the PMOS tube can reach a threshold voltage, thereby ensuring the turning on of the PMOS tube.
7. The fast discharge circuit according to claim 6, characterized in that: The control circuit also includes a second diode, the anode of the second diode is connected to the other end of the second resistor, and the cathode is connected to the power on / off control signal source to prevent the high level of the power on / off control signal source from being transmitted to the high potential power supply during the power-on phase, thereby burning out the high potential power supply.
8. A vehicle-mounted domain controller, characterized in that: The vehicle-mounted domain controller includes the fast discharge circuit described in any one of claims 1 to 7.