Switching circuit and vehicle body domain controller
By designing a switching circuit including a controller, a latch module, an IO extender and a switching chip in the area controller, the problem that the distribution switching chip cannot maintain a very high output in the MCU RESET state is solved, and multiple output expansion is achieved, saving PCB area and cost, and improving reliability.
Patent Information
- Application Number
- CN202421657576.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-12
- Publication Date
- 2025-05-16
- Estimated Expiration
- 2034-07-12
AI Technical Summary
In the existing area controller, the power distribution switch chip cannot maintain a normal high output in the MCU RESET state, resulting in the power distribution switch being in an unexpectedly disconnected state, increasing the cost and occupying the printed circuit board area.
Design a switching circuit, including a controller, latch module, IO extender and switching chip, multi-output expansion through the IO extender, maintain the latch state, save PCB area, and reduce costs.
While maintaining the latch state, multiple output expansion is achieved through the extender, which reduces the multiple arrangement of the latch module, saves PCB area, reduces costs, and improves overall reliability.
Smart Images
Figure CN222882954U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of regional controllers, in particular to a switch circuit and a vehicle body domain controller. Background Art
[0002] Currently, there are a large number of primary / secondary power distribution switches in the regional controller (Zonal Control Unit, ZCU). The control pins of these power distribution chips are directly controlled by the microcontroller unit (MCU), such as Figure 1 When a hard reset occurs due to vehicle state switching or a soft reset occurs due to software mode jump, the MCU port is in an uncontrollable Hi-Z state in the RESET state. At this time, the input pin of the power distribution switch chip cannot maintain a normal high output, and the power distribution switch is in an unexpected disconnected state.
[0003] In view of the above situation, in order to avoid the loss of power supply to the subsequent load, the power distribution needs to be latched. The latching scheme used in the related art is shown in the figure below: Figure 2 As shown, the working principle of the circuit is as follows: when the MCU first sends out a switch enable signal (high level), transistor T1 is turned on, transistor T2 is turned on, and the level at point A is equal to the VS level. When the MCU is in the RESET state, the MCU port changes to the Hi-Z state. Since T2 is turned on, points A and B are both high levels, T1 and T2 can maintain the on state, the IN pin of the high side driver (High Side Driver, HSD) chip is latched as a high level, and the switch is continuously turned on. However, the current regional controller is highly integrated and has a large number of power distribution channels. The use of solutions such as those in the related art for output latching has at least the following defects: each power distribution needs to add a latch circuit, which has many devices and occupies the area of the printed circuit board (PCB), and its cost is high. Summary of the invention
[0004] In view of the above shortcomings of the prior art, the purpose of the utility model is to provide a switching circuit and a body domain controller. The switching circuit is based on the arrangement of an expander, a latch module and a switch chip. It can perform multi-channel output expansion through the expander while maintaining the latch state, thereby saving PCB area and reducing costs.
[0005] The utility model embodiment discloses a switch circuit, including a controller, a latch module, an IO expander and a switch chip; the first output end of the controller is electrically connected to the control end of the latch module, the second output end of the controller is electrically connected to the control end of the IO expander, the latch module is connected in series between a power supply and the IO expander, the output end of the IO expander is electrically connected to the switch chip, and the switch chip is used to receive a control signal sent by the IO expander and output an enable signal to a load according to the control signal.
[0006] Furthermore, there are multiple switch chips, and input ends of the multiple switch chips are electrically connected to multiple output ends of the IO expander respectively.
[0007] Further, the latch module includes a third resistor, a fourth resistor, a fifth resistor, a first transistor and a second transistor; one end of the third resistor is electrically connected to the first output end of the controller, the other end of the third resistor is electrically connected to the base of the first transistor, one end of the fifth resistor is electrically connected to the connection node between the third resistor and the controller, the other end of the fifth resistor is electrically connected to the fourth resistor, the collector of the first transistor is electrically connected to the base of the second transistor, the emitter of the second transistor is connected to the power supply, the collector of the second transistor is electrically connected to one end of the fourth resistor, and the other end of the fourth resistor is electrically connected to the power supply end of the IO expander.
[0008] Furthermore, the first transistor is an NPN transistor.
[0009] Furthermore, the second transistor is a PNP transistor.
[0010] Furthermore, it also includes an output resistor, one end of the output resistor is electrically connected to the output end of the IO expander, and the other end of the output resistor is electrically connected to the input end of the switch chip.
[0011] Furthermore, the switch chip is a high-side drive switch chip.
[0012] Furthermore, the controller is used to generate a control instruction and transmit the control instruction to the control end of the IO expander via the second output end and the I2C bus.
[0013] Furthermore, the controller is a microcontroller.
[0014] The embodiment of the utility model also discloses a vehicle body domain controller, comprising the above-mentioned switch circuit.
[0015] The switch circuit provided by the utility model has the following beneficial effects, including but not limited to:
[0016] 1) The switch circuit has high integration, and the IO expander it uses can support multi-channel output expansion, reducing the multiple layout and use of latch modules and saving PCB area;
[0017] 2) In the switch circuit, the controller sends instructions through I2C communication. When the controller fails, the possibility of IO expander malfunctioning through the I2C bus is reduced, thereby improving the overall reliability;
[0018] 3) In the switch circuit, one IO expander can support multi-channel output expansion, and the cost of a single IO expander is lower than the cost of building a latch module for each channel separately. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] This specification will be further described in the form of exemplary embodiments, which will be described in detail by the accompanying drawings. These embodiments are not restrictive, and in these embodiments, the same number represents the same structure, wherein:
[0020] Figure 1 A schematic diagram of a power distribution switch of a ZCU in the related art;
[0021] Figure 2 It is a structural schematic diagram of a switch circuit in the related art;
[0022] Figure 3 A schematic diagram of the structure of a switch circuit provided in an embodiment of the utility model. DETAILED DESCRIPTION
[0023] The following describes the implementation of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.
[0024] It should be noted that the illustrations provided in the following embodiments are only used to schematically illustrate the basic concept of the present invention, and thus the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.
[0025] Figure 3 The schematic diagram of the structure of the switch circuit provided by the embodiment of the utility model is shown in FIG. Figure 3As shown, the utility model provides a switching circuit, which includes a controller, a latch module, an IO expander and a switch chip; the first output end of the controller is electrically connected to the control end of the latch module, the second output end of the controller is electrically connected to the control end of the IO expander, the latch module is connected in series between the power supply and the IO expander, the output end of the IO expander is electrically connected to the switch chip, and the switch chip is used to receive a control signal sent by the IO expander and output an enable signal to the load according to the control signal.
[0026] It is worth noting that the switch circuit is based on the arrangement of the expander, latch module and switch chip, which can perform multi-channel output expansion through the expander while maintaining the latch state, saving PCB area and reducing costs.
[0027] In this embodiment, there are multiple switch chips, and input ends of the multiple switch chips are electrically connected to multiple output ends of the IO expander respectively.
[0028] It is worth noting that the number of switch chips can be determined according to the needs of the specific implementation environment, and the output end of each switch chip can be electrically connected to a load to achieve control of the load working state. In addition, the IO expander in this embodiment can be an IO expansion chip in the related art. In this embodiment, the output expansion of 16 or more channels can be achieved by increasing the number of IO expansion chips. Specifically, the number of expansion channels of the switch circuit during the application process can also be determined based on the specific implementation environment. There is a phenomenon that the number of output ends of the IO expander is greater than the number of switch chips, so as to improve the adaptability of the switch circuit to different working conditions.
[0029] It is also worth noting that in the switch circuit, the cost of a single IO expander is lower than the cost of building a latch module for each channel. Compared with the technical solutions in the related art, it can reduce the use of latch modules, improve integration, and reduce the cost of use.
[0030] Please refer again Figure 3 The latch module includes a third resistor, a fourth resistor, a fifth resistor, a first transistor and a second transistor; one end of the third resistor is electrically connected to the first output end of the controller, the other end of the third resistor is electrically connected to the base of the first transistor, one end of the fifth resistor is electrically connected to the connection node between the third resistor and the controller, the other end of the fifth resistor is electrically connected to the fourth resistor, the collector of the first transistor is electrically connected to the base of the second transistor, the emitter of the second transistor is connected to the power supply, the collector of the second transistor is electrically connected to one end of the fourth resistor, and the other end of the fourth resistor is electrically connected to the power supply end of the IO expander.
[0031] In this embodiment, the first transistor is an NPN transistor and the second transistor is a PNP transistor. It is understandable that NPN and PNP are two common types of transistor structures, which are one of the two most basic types of bipolar transistors. The NNPN transistor is composed of two n-type semiconductors sandwiching a p-type semiconductor. In the NPN transistor, two n-type semiconductors (emitter and collector) are sandwiched between a p-type semiconductor (base). When a positive voltage is applied to the base, current flows from the emitter to the collector. The PNP transistor is opposite to the NPN transistor. The PNP transistor is composed of two p-type semiconductors sandwiching an n-type semiconductor. In the PNP transistor, two p-type semiconductors (emitter and collector) are sandwiched between an n-type semiconductor (base). When a negative voltage is applied to the base, current flows from the collector to the emitter. It can also be understood that the circuit structure of the latch module can also be other circuit structures that can be used for state latching, which can be various latch circuits in the relevant technology, as long as it can play the function of state latching. This embodiment does not constitute a limitation on the specific structural type of the latch module, but is only an example of it.
[0032] Please refer again Figure 3 , the switch circuit further includes an output resistor, one end of the output resistor is electrically connected to the output end of the IO expander, and the other end of the output resistor is electrically connected to the input end of the switch chip. It can be understood that the output resistor in this embodiment is used in conjunction with the switch chip. As shown in the figure, S1 and S2 are both output resistors, which are used in conjunction with the first high-side driver switch chip (HSD1) and the second high-side driver switch chip (HSD2) respectively.
[0033] In this embodiment, the controller is used to generate a control instruction and transmit the control instruction to the control end of the IO expander via the second output end and the I2C bus.
[0034] It is worth noting that in the switch circuit, the controller sends control instructions through I2C communication. When the controller fails, the possibility of malfunction of the IO expander through the I2C bus is reduced, thereby improving the overall reliability of the circuit structure.
[0035] In this embodiment, the controller is a microcontroller unit (MCU).
[0036] In summary, the controller in this embodiment is used to issue an enable instruction, and the enable instruction is used to pull up Figure 3The signal at point B turns on transistor T1, transistor T2, and IO expander S2 is powered through transistor T2; the controller sends a control instruction through the I2C bus to control IO expander S2 to output a high level, enabling switch chips S3 and S4, and OU1 and OUT2 to output externally. When the MCU is in the RESET state, the controller port state changes to Hi-Z; at this time, since transistor T2 is turned on, point A is pulled high by the VS voltage, point B is also high, transistors T1 and T2 remain turned on, the power supply of IO expander S2 is in a maintained state, the register state inside the IO expander remains unchanged, the chip output is high, the chip IN pins of HSD1 and HSD2 are high, and OUT1 and OUT2 maintain output.
[0037] This embodiment also provides a vehicle body domain controller, including the above-mentioned switch circuit, having all its beneficial effects.
[0038] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed in the present invention shall still be covered by the claims of the present invention.
[0039] In the description herein, many specific details, such as examples of components and / or methods, are provided to provide a complete understanding of the embodiments of the present invention. However, those skilled in the art will recognize that embodiments of the present invention may be practiced without one or more specific details or by other devices, systems, components, methods, components, materials, parts, etc. In other cases, well-known structures, materials, or operations are not specifically shown or described in detail to avoid obscuring aspects of the embodiments of the present invention.
[0040] References throughout the specification to "one embodiment," "an embodiment," or "a specific embodiment" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present invention, and not necessarily in all embodiments. Thus, various appearances of the phrases "in one embodiment," "in an embodiment," or "in a specific embodiment" in different places throughout the specification do not necessarily refer to the same embodiment. In addition, the particular features, structures, or characteristics of any specific embodiment of the present invention may be combined with one or more other embodiments in any suitable manner. It should be understood that other variations and modifications of the embodiments of the present invention described herein and shown may be based on the teachings herein and will be considered part of the spirit and scope of the present invention.
[0041] It should also be understood that one or more of the elements shown in the figures may also be implemented in a more separate or more integrated manner, or even removed because they are inoperable in certain circumstances or provided because they may be useful depending on the application.
[0042] In addition, unless otherwise explicitly indicated, any marking arrows in the drawings should be regarded as exemplary only and not limiting. In addition, unless otherwise indicated, the term "or" used herein is generally intended to mean "and / or". In the case where the term is not clear because it is anticipated that the ability to separate or combine is provided, the combination of components or steps will also be regarded as indicated.
[0043] As used in the description herein and throughout the claims that follow, "a", "an", and "the" include plural references unless otherwise indicated. Likewise, as used in the description herein and throughout the claims that follow, the meaning of "in" includes "in" and "on" unless otherwise indicated.
[0044] The above description of the illustrated embodiments of the present invention (including the contents in the abstract of the specification) is not intended to be an exhaustive list or to limit the present invention to the precise form disclosed herein. Although specific embodiments of the present invention and examples of the present invention are described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the present invention as will be recognized and understood by those skilled in the art. As noted, these modifications may be made to the present invention in accordance with the above description of the embodiments of the present invention, and these modifications will be within the spirit and scope of the present invention.
[0045] Systems and methods have been generally described herein as details that are helpful for understanding the present invention. In addition, various specific details have been given to provide an overall understanding of the embodiments of the present invention. However, those skilled in the relevant art will recognize that the embodiments of the present invention can be practiced without one or more specific details, or practiced using other devices, systems, accessories, methods, components, materials, parts, etc. In other cases, well-known structures, materials, and / or operations are not specifically shown or described in detail to avoid confusion with various aspects of the embodiments of the present invention.
Claims
1. A switching circuit, characterized in that: Including controller, latch module, IO expander and switch chip; The first output end of the controller is electrically connected to the control end of the latch module, the second output end of the controller is electrically connected to the control end of the IO expander, the latch module is connected in series between the power supply and the IO expander, the output end of the IO expander is electrically connected to the switch chip, and the switch chip is used to receive a control signal sent by the IO expander and output an enable signal to the load according to the control signal.
2. The switch circuit according to claim 1, characterized in that: There are multiple switch chips, and input ends of the multiple switch chips are electrically connected to multiple output ends of the IO expander respectively.
3. The switch circuit according to claim 1, characterized in that: The latch module includes a third resistor, a fourth resistor, a fifth resistor, a first transistor and a second transistor; one end of the third resistor is electrically connected to the first output end of the controller, the other end of the third resistor is electrically connected to the base of the first transistor, one end of the fifth resistor is electrically connected to the connection node between the third resistor and the controller, the other end of the fifth resistor is electrically connected to the fourth resistor, the collector of the first transistor is electrically connected to the base of the second transistor, the emitter of the second transistor is connected to the power supply, the collector of the second transistor is electrically connected to one end of the fourth resistor, and the other end of the fourth resistor is electrically connected to the power supply end of the IO expander.
4. The switch circuit according to claim 3, characterized in that: The first transistor is an NPN transistor.
5. The switch circuit according to claim 3, characterized in that: The second transistor is a PNP transistor.
6. The switch circuit according to claim 1, characterized in that: It also includes an output resistor, one end of which is electrically connected to the output end of the IO expander, and the other end of which is electrically connected to the input end of the switch chip.
7. The switch circuit according to claim 1, characterized in that: The switch chip is a high-side drive switch chip.
8. The switch circuit according to claim 1, characterized in that: The controller is used to generate a control instruction and transmit the control instruction to the control end of the IO expander via the second output end and the I2C bus.
9. The switch circuit according to claim 1, characterized in that: The controller is a microcontroller.
10. A vehicle body domain controller, characterized in that: Comprising a switching circuit as described in any one of claims 1 to 9.