Short-circuit protection circuit for hidden door handle control
By using the circuit design of the current diversion transistor and the protection transistor in the hidden door handle control, short-circuit protection is achieved based on the self-switching of current changes, solving the problem of dependence on high-priced chips in the existing technology, realizing dechirization and cost reduction effect.
Patent Information
- Application Number
- CN202323570376.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-27
- Publication Date
- 2024-12-24
- Estimated Expiration
- 2033-12-27
AI Technical Summary
The existing short-circuit protection circuits for hidden door handles rely on high-priced integrated control chips, and the chip procurement cycle is unstable, making it difficult to adapt to the cost control needs of low-end products, and have poor design flexibility.
A short-circuit protection circuit including several current diversion transistors and protection transistors is designed to switch the on/off state of the transistor by changing the current, short-circuit protection is achieved, reducing dependence on the chip, and the pure circuit characteristics are adopted without software participation.
It realizes dechirization of hidden door handle short-circuit protection, reduces costs, has more direct control, automatic recovery function, and is flexible, avoiding the impact of chip price and production capacity.
Smart Images
Figure CN222234422U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of automobile electric control protection, in particular to a short-circuit protection circuit for controlling a hidden door handle. Background Art
[0002] With the rapid development of electronic technology, automobile development is also tending towards electrification. With the application of a large number of electronic technologies in automobiles, the requirements for circuit protection are also more perfect. For some relatively low-end electronic circuit development, the higher-priced integrated control chips are not suitable. In addition, affected by the production capacity of integrated chips, integrated control chips often have a long procurement cycle and unstable prices, which affects the progress of hardware development. Products with high cost control requirements cannot reduce costs in integrated chips.
[0003] The existing short-circuit protection method for the control circuit in the electric hidden door handle generally uses an integrated chip that integrates control and protection, combined with a software sampling feedback circuit to achieve short-circuit or overcurrent protection, but its price is relatively high and is not applicable to some low-end products. In addition, some chips are affected by production capacity and the procurement cycle is unstable. If it is for a simple circuit design, there is no suitable chip selection, and even a small change in the design may require software cooperation, which is inflexible. Utility Model Content
[0004] In order to reduce the dependence of the hidden door handle on the chip in short-circuit protection and reduce the cost, the utility model proposes a short-circuit protection circuit for hidden door handle control, including a plurality of current-conducting transistors and a protection transistor, wherein:
[0005] When the circuit is operating normally, the circuit current is within a safe value, the protection transistor is in the off state, each current conducting transistor is in the on state, and the power output supplies power to the door handle load board;
[0006] When a short circuit occurs in the circuit, the circuit current exceeds the safety value, the protection transistor enters the on state, and each current-conducting transistor is controlled to enter the off state, cutting off the power supply output to the door handle load board.
[0007] Furthermore, when the circuit is in normal working state, the power supply and the door handle load board are connected through a first resistor, and the protection transistor switches the conduction state of the circuit current flowing through the first resistor based on a safety value judgment by connecting the emitter and the base to both sides of the first resistor.
[0008] Furthermore, the plurality of current-conducting transistors include a second current-conducting transistor and a third current-conducting transistor, wherein the base of the third current-conducting transistor is connected to the high-level signal output by the main control chip.
[0009] Furthermore, when a short circuit occurs in the circuit, the protection transistor enters a conducting state, and the collector of the protection transistor outputs a high-level signal to the base of the second current-conducting transistor.
[0010] Furthermore, when the circuit is in normal working condition, the third conducting transistor is turned on so that the base of the second conducting transistor is grounded through the second resistor, the voltage difference between the emitter of the second conducting transistor and the base of the second conducting transistor is greater than the turn-on voltage, the second conducting transistor enters the on state, the power supply output supplies power and is supplied to the door handle load board through the first resistor.
[0011] Furthermore, when a short circuit occurs in the circuit, since the voltage at the emitter of the second current-conducting transistor is less than the voltage at the base of the second current-conducting transistor, the second current-conducting transistor enters a shutdown state, cutting off the power supply output to the door handle load board.
[0012] Compared with the prior art, the utility model has at least the following beneficial effects:
[0013] The utility model discloses a short-circuit protection circuit for controlling a concealed door handle. By utilizing the on / off electrical characteristics of transistors and based on the change of current in the circuit, the short-circuit protection is performed by automatically switching the on states of a number of transistors, thereby realizing the de-chipization of the short-circuit protection of the electrical control of the concealed door handle. At the same time, there is no need to perform data analysis and judgment, and the control is more direct, thereby reducing costs and increasing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 The invention is a circuit diagram of a short circuit protection circuit for hidden door handle control. DETAILED DESCRIPTION
[0015] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.
[0016] In order to intervene in time when a short circuit occurs in a hidden door handle, and avoid the problem of the door handle being mis-clamped or unable to be opened due to a short circuit out of control, the utility model proposes a short circuit protection circuit for controlling a hidden door handle, including a plurality of current-conducting transistors and a protection transistor, wherein:
[0017] When the circuit is operating normally, the circuit current is within a safe value, the protection transistor is in the off state, each current conducting transistor is in the on state, and the power output supplies power to the door handle load board;
[0018] When a short circuit occurs in the circuit, the circuit current exceeds the safety value, the protection transistor enters the on state, and each current-conducting transistor is controlled to enter the off state, cutting off the power supply output to the door handle load board.
[0019] like Figure 1 The circuit diagram is shown in a connection mode of the short-circuit protection circuit according to the utility model, and the circuit includes a protection transistor Q1, a second current-conducting transistor Q2 and a third current-conducting transistor Q3. Among them, the base of the third current-conducting transistor Q3 is connected to the IO signal of the main control chip, the emitter is grounded, and the collector is connected to one end of the second resistor R2; the base of the second current-conducting transistor Q2 is connected to the other end of the second resistor R2, the collector is connected to the first connector of the connector, and the emitter is connected to the power supply VS through the first resistor R1; the emitter of the protection transistor Q1 is connected to the near power supply end of the first resistor R1, the base is connected to the far power supply end of the first resistor R1, and the collector is connected to the base of the second current-conducting transistor Q2; the first interface of the connector is also connected to the negative electrode of the first diode D1, the positive electrode of the first diode D1 is connected to the emitter of the third current-conducting transistor Q3, and the second connector of the connector is grounded. The connector is used to connect to the power supply interface of the door handle load board for power supply.
[0020] It is not difficult to see from the circuit diagram that when the IO signal output by the main control chip MCU is at a high level and the circuit is in normal working condition, the voltage difference between the emitter and the base of the protection transistor Q1 does not exceed the safe value (which can be adjusted by adjusting the resistance of the first resistor R1) because the circuit current does not exceed the safe value. Therefore, the protection transistor Q1 is in the off state at this time, so the power supply flows to the second current-conducting transistor Q2 through the first resistor. Since the emitter of the third current-conducting transistor Q3 is grounded, when the IO signal output by the main control chip is at a high level, the third current-conducting transistor Q3 is also in the on state. At this time, the base of the second current-conducting transistor Q2 is equivalent to grounding, so the second current-conducting transistor is also in the on state at this time, and the power supply can be directly output to the door handle load board.
[0021] When a short circuit or a fault occurs in the circuit causing the circuit current to exceed the safe value, the circuit current increases and the voltage difference between the emitter and the base of the protection transistor Q1 exceeds the conduction voltage. Therefore, the protection transistor Q1 enters the conduction state, and the power supply voltage is directly output to the base of the second current-conducting transistor Q2. In this way, due to the first resistor R1, the voltage at the base of the second current-conducting transistor Q2 is greater than the voltage at the emitter, and the second current-conducting transistor Q2 enters the off state, thereby blocking the power supply voltage output to the connector, thereby realizing the short-circuit protection function.
[0022] When the circuit current returns to a safe value, the voltage difference across the first resistor R1 is not enough to protect the transistor Q1 from turning on, and the power supply to the door handle load board is restored, and the function returns to normal.
[0023] Through the short-circuit protection circuit design based on pure circuit characteristics, effective protection can be achieved without software involvement. The function will be automatically restored when the short circuit or fault is removed. At the same time, the components used in the circuit are all discrete components, which are low-priced and have many alternative models. There is no concern about material shortages, and they can also be matched and constructed according to actual needs, which is flexible and changeable.
[0024] To sum up, the short-circuit protection circuit for hidden door handle control described in the utility model, by utilizing the on / off electrical characteristics of the transistor, based on the change of current in the circuit, performs short-circuit protection by automatically switching the on states of several transistors, thereby realizing the de-chipization of the short-circuit protection of the hidden door handle electrical control. At the same time, there is no need for data analysis and judgment, the control is more direct, and costs are reduced and efficiency is increased.
[0025] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) 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] In addition, in the present invention, the descriptions of "first", "second", "one", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0027] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0028] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.
Claims
1. A short circuit protection circuit for hidden door handle control, characterized in that: It includes several conducting transistors and a protection transistor, among which: When the circuit is operating normally, the circuit current is within a safe value, the protection transistor is in the off state, each current conducting transistor is in the on state, and the power output supplies power to the door handle load board; When a short circuit occurs in the circuit, the circuit current exceeds the safety value, the protection transistor enters the on state, and each current-conducting transistor is controlled to enter the off state, cutting off the power supply output to the door handle load board.
2. A short-circuit protection circuit for hidden door handle control as claimed in claim 1, characterized in that: When the circuit is in normal working state, the power supply and the door handle load board are connected through the first resistor, and the protection transistor switches the conduction state of the circuit current flowing through the first resistor based on the safety value judgment by connecting the emitter and the base to the two sides of the first resistor.
3. A short-circuit protection circuit for hidden door handle control as claimed in claim 2, characterized in that: The plurality of current-conducting transistors include a second current-conducting transistor and a third current-conducting transistor, wherein the base of the third current-conducting transistor is connected to a high-level signal output by the main control chip.
4. A short-circuit protection circuit for hidden door handle control as claimed in claim 3, characterized in that: When a short circuit occurs in the circuit, the protection transistor enters a conducting state, and the collector of the protection transistor outputs a high level signal to the base of the second current conducting transistor.
5. A short circuit protection circuit for hidden door handle control as claimed in claim 3, characterized in that: When the circuit is in normal working state, the third conduction transistor is turned on so that the base of the second conduction transistor is grounded through the second resistor, the voltage difference between the emitter of the second conduction transistor and the base of the second conduction transistor is greater than the conduction voltage, the second conduction transistor enters the conduction state, the power supply output supplies power and is supplied to the door handle load board through the first resistor.
6. A short circuit protection circuit for hidden door handle control as claimed in claim 4, characterized in that: When a short circuit occurs in the circuit, since the voltage at the emitter of the second conducting transistor is less than the voltage at the base of the second conducting transistor, the second conducting transistor enters a shutdown state, cutting off the power supply output to the door handle load board.