WO2020037912A1

WO2020037912A1 - Beidou navigation system based vehicle-mounted inteligent terminal

Info

Publication number: WO2020037912A1
Application number: PCT/CN2018/123040
Authority: WO
Inventors: 刘贵生; 刘志钢; 苍海涛
Original assignee: 北斗航天汽车（北京）有限公司
Priority date: 2018-08-24
Filing date: 2018-12-24
Publication date: 2020-02-27
Also published as: CN108809078A

Abstract

The present invention relates to the technical field of vehicle-mounted intelligent terminals for automobiles and in particular relates to a Beidou navigation system-based vehicle-mounted intelligent terminal, comprising: a terminal power supply, a power supply management module and a central controller; the central controller is electrically connected by a signal line with an enable signal end of the power supply management module; and the power supply management module is electrically connected by a power supply line with a movement sensing module, a Beidou navigation module, a bluetooth module, a 4G module and a CAN port module, respectively. According to the Beidou navigation system-based vehicle-mounted intelligent terminal, when the central controller does not output the enable signal, the demands of the vehicle-mounted intelligent terminal for static currents can be completely satisfied, thereby solving the problem of high static power consumption of the controller; when the central controller outputs the enable signal, due to a high switching frequency of a DCDC power conversion chip, the power conversion efficiency is high.

Description

Vehicle-mounted intelligent terminal based on Beidou navigation system

Technical field

The invention relates to the technical field of vehicle-mounted intelligent terminals for automobiles, and in particular to a vehicle-mounted intelligent terminal based on a Beidou navigation system.

Background technique

New energy vehicles are the main development direction of the automotive field today. With the development of electronic technology, the management of power for smart vehicle terminal controllers is increasingly demanding. The design of this power management mainly considers two aspects, one is to ensure that the controller's static power consumption is very low, and the other is to ensure that the controller The efficiency of electricity consumption during normal work is very high. According to the design standards for the static power consumption of the entire vehicle, each controller must enter the sleep or ultra-low power consumption mode when it is not working, which can ensure the service life of the vehicle's low-voltage battery (usually 12V). At the same time, considering that the current low-voltage controller of pure electric new energy vehicles comes from the high-voltage battery pack, and the power of the high-voltage battery pack is certain, so when designing each controller on a pure electric new-energy vehicle, it is necessary to ensure control The power efficiency of the device during normal operation. The existing power supply system of the vehicle terminal controller either has a high static power consumption of the controller, or the power efficiency during the normal operation of the controller is not very high, and cannot meet the above two requirements at the same time. .

At the same time, the reliability requirements for the power supply of vehicle-mounted communication devices (such as TBOX devices) are getting higher and higher, because vehicle-mounted communication devices need continuous power supply for outputting vehicle position information and monitoring and control information. Vehicle-mounted communication devices require uninterrupted power supply. Most uninterruptible power supply systems are composed of a vehicle main power supply and a backup power supply. After the vehicle main power supply is powered down, the electronic equipment can still work normally under the backup battery power supply. The switching technology between the vehicle's main power supply and the backup power supply is widely used in dual power supply application scenarios. The traditional power switching scheme uses the single-phase conduction characteristics of the diode to switch the vehicle's main power supply and backup power supply, but the forward voltage drop and forward resistance of the diode make it less efficient, and the application cost is increased due to the addition of the diode. Increase.

In addition, CAN bus is widely used in industrial automation, marine, medical equipment and other fields due to its high performance and reliability. Especially in the field of automotive electronics, the CAN bus is often used in power system networks directly related to safety. However, in the process of high-speed signal transmission, there are a large number of interference signals and electrostatic interference, which brings great trouble to the later signal processing. The existing CAN analysis circuit has poor anti-interference performance and serious fault tolerance, which greatly affects the safety and reliability of signals at high speed transmission.

Therefore, in order to solve the above problems, it is urgent to invent a new vehicle-mounted intelligent terminal based on the Beidou navigation system.

Summary of the Invention

The purpose of the present invention is to provide a vehicle-mounted intelligent terminal based on the Beidou navigation system, which realizes that the static power consumption of the vehicle-mounted terminal is very low, and at the same time, the power consumption efficiency during the normal operation of the controller is very high.

The present invention provides the following solutions:

A vehicle-mounted intelligent terminal based on a Beidou navigation system includes a terminal power supply with an automatic switching function of a vehicle main power supply and a backup power supply, a power management module with high-efficiency power conversion efficiency, and a central controller. The terminal power supply and the power management module And the central controller is electrically connected in sequence through a power supply line, and the central controller is electrically connected to an enable signal terminal of the power management module through a signal line; the power management module is respectively connected to a motion sensing module through a power supply line, The Beidou navigation module, wireless communication module and CAN port module with analysis function are electrically connected. The motion sensing module, the Beidou navigation module, the wireless communication module and the CAN port module are respectively connected to the center through signal lines. The controller is electrically connected.

Preferably, the power management module includes a DCDC power conversion circuit, a first power conversion circuit, and a second power conversion circuit. A power input terminal of the DCDC power conversion circuit is electrically connected to the terminal power supply through a power supply line. A power conversion circuit and the second power conversion circuit are respectively electrically connected to a conversion power output terminal of the DCDC power conversion circuit, and a driving current threshold of the first power conversion circuit is greater than a driving current of the second power conversion circuit. Threshold; the output end of the first conversion circuit is electrically connected to the 4G module of the wireless communication module through a power supply line, and the output end of the second power conversion circuit is connected to the motion sensing module and the The Beidou navigation module, the Bluetooth module of the wireless communication module, the central controller and the CAN port module are electrically connected.

Preferably, the DCDC power conversion circuit is a DCDC power conversion chip, a power input terminal of the DCDC power conversion chip is connected to the terminal power source, an enable end of the DCDC power conversion chip is connected to the central controller, and The conversion output terminal of the DCDC power conversion chip is connected to one end of an inductor, and the other end of the inductor L is connected to the conversion power output terminal.

Preferably, the first power conversion circuit includes a high current power conversion chip, a power input terminal of the high current power conversion chip is connected to the conversion power output terminal, and an output end of the high current power conversion chip is connected to the The 4G module of the wireless communication module is connected, the enable end of the high-current power conversion chip is connected to one end of a sixth resistor, and the other end of the sixth resistor is connected to the central controller.

Preferably, the second power conversion circuit includes a small current power conversion chip, a power input terminal of the small current power conversion chip is connected to the conversion power output terminal, and an output end of the small current power conversion chip is connected through a power supply line. It is electrically connected to the motion sensing module, the Beidou navigation module, the Bluetooth module of the wireless communication module, the central controller and the CAN port module, respectively.

Preferably, the terminal power source includes a vehicle main power source, a backup power source, and an automatic switching circuit, and the vehicle main power source and the backup power source are electrically connected to the automatic switching circuit through a power supply line, respectively, and an output terminal of the automatic switching circuit It is electrically connected to a power input terminal of the DCDC power conversion circuit through a power supply line.

Preferably, the automatic switching circuit includes a 203 transistor, a 203 transistor, and a 203 transistor;

The first output terminal of the two hundred and three transistor is connected to the power output terminal, and the second output terminal of the two hundred and three transistor is connected to the first one of the two hundred twenty three transistor. The output terminal is connected, and a 201 resistance is connected between the input terminal of the 203 transistor and the second output terminal of the 211 transistor; the power output terminal is connected to The power input terminal of the DCDC power conversion circuit is electrically connected;

The input terminal of the second transistor is connected to the first output terminal of the second transistor, and the second output terminal of the second transistor is grounded. A 205 resistor is connected between the input terminal of the 203 transistor and the second output terminal of the 203 transistor;

A second output terminal of the 203 triode is grounded, and an input terminal of the 203 triode is connected to a second output terminal of the 203 triode. 207 resistance

A backup power source is connected in series between the input terminal of the 203 transistor and the first output terminal of the 203 transistor; the first output terminal of the 203 transistor And the main terminal of the vehicle is connected in series with the input terminal of the 203 triode.

Preferably, the CAN port module includes a CAN analysis circuit, the CAN analysis circuit is electrically connected to an output of the second power conversion circuit through a power supply line, and the CAN analysis circuit is electrically connected to the central controller through a signal line. connection.

Preferably, the CAN analysis circuit includes a CAN transceiver and a common mode inductor;

The CAN transceiver is provided with a transmitting end for sending a CAN parameter signal to the central controller and a receiving end for receiving a control signal sent from the central processor; and a high voltage end and a low voltage end are also provided;

The common mode inductor includes a 301st inductor and a 302nd inductor in a common mode induction setting, wherein a first terminal of the 301st inductor is connected to the high voltage terminal, so The second end of the 301st inductor is used for connection with a high-voltage signal line of the CAN bus; the first end of the 302nd inductor is connected to the low voltage end, and the 302nd inductor The second end is used to connect with the low-voltage signal line of the CAN bus.

Preferably, the CAN analysis circuit further includes an anti-static protection diode unit. A first end of the anti-static protection diode unit is connected to a second end of the 302 inductor. The second terminal is connected to the second terminal of the 301st inductor, and the third terminal of the anti-static protection diode unit is grounded.

The beneficial effects of the present invention:

1. The vehicle-mounted intelligent terminal based on the Beidou navigation system disclosed in the present invention, when the central controller does not output an enable signal, only the DCDC power conversion circuit in the power management module is charged, and the static current of the entire circuit and the DCDC power conversion circuit The static current is basically the same, because the static current of the DCDC power conversion circuit is very small, which can fully meet the requirements of the vehicle terminal controller for the static current, which solves the problem of relatively high static power consumption of the controller; When the signal is available, the DCDC power conversion circuit starts to work, and the first power conversion circuit, the second power conversion circuit, and the fifth power conversion circuit in the power management module start to work. Due to the very high switching frequency of the DCDC power conversion chip, its power supply The conversion efficiency is also very high. Even if the power conversion efficiency of the first power conversion circuit, the second power conversion circuit, and the fifth power conversion circuit is relatively low, the comprehensive efficiency can reach the optimal balance, which can ensure the interference of the application components on the ripple. And saved costs.

2. The first power conversion circuit includes a high current power conversion chip, a power input terminal 10 of the high current power conversion chip is connected to the conversion power output terminal, and an output terminal 11 of the high current power conversion chip is connected to a first One is connected with an electric unit, the enable terminal 12 of the high-current power conversion chip is connected to one end of a sixth resistor R6, and the other end of the sixth resistor is connected to the central controller; The enable control of the high-current power conversion chip further reduces the interference of the first power consumption unit on the ripple, and solves the problem that some components are sensitive to the power ripple.

3. The high-current power conversion chip, the low-current power conversion chip, and the second low-current power conversion chip all use automotive-grade power chips, which solves the problem of terminal power management stability.

4. Through the automatic switching circuit composed of the 201st transistor Q201, the 20023 transistor Q202 and the 2003 transistor Q203, the power supply of the power output end of the power supply for the vehicle communication device is realized. Seamless switching between standby power supply and vehicle main power supply, solves the problem of uninterrupted power supply of vehicle communication devices and the problem of switching between two sets of power supply systems, does not require MCU control such as single chip microcomputer, and automatically switches according to different external conditions. Simple structure, smart design, low cost, stable performance, can be fine-tuned according to different environments.

5. The first output terminal of the two hundred and three transistor Q201 is connected to the vehicle main power supply through the two hundred diode D200, and the first output terminal of the two hundred and three transistor Q203 is connected through the first The 203 resistor R203 is connected to the backup power source, and the input terminal of the 203 transistor Q203 is connected to the vehicle main power source through the 206 resistor R6. The 203 transistor Q201 The second output terminal of the second transistor Q202 is connected to the first output terminal of the second transistor Q202 through the second 202 resistor; The zero-four resistor R204 is connected to the first output terminal of the two hundred and three triode Q203; by setting a plurality of different voltage-dividing resistors, the switching speed of the power supply can be adjusted and the controllability of the circuit can be achieved;

6. The automatic switching circuit further includes a 201st capacitor C201, a 202nd capacitor C202, and a 203rd capacitor C203, and the first capacitor plate of the 203rd capacitor C203 and the The common connection point of the 206th resistor R206 and the 207th resistor R7 are connected, and the second capacitor plate of the 203rd capacitor C203 is grounded; A capacitor plate is connected to the first output terminal of the 201st transistor Q201, a second capacitor plate of the 201st capacitor C201 is grounded, and the 202nd capacitor C202 is connected to the The 201st capacitor C201 is connected in parallel; by setting a buffer capacitor, in the process of power supply switching, it plays a buffer effect on the voltage drop and rise, reducing the impact on the circuit and improving the stability and reliability of the circuit.

7. The CAN analysis circuit is provided with a CAN transceiver and a common mode inductor, and uses the common mode inductor to filter the common mode electromagnetic interference signals, and at the same time plays the role of EMI filtering, and suppresses the electromagnetic waves generated by high-speed signal lines from radiating outward. , Improve the anti-interference ability of the CAN analysis circuit, and ensure the reliability of the signal in high-speed transmission;

8. The CAN analysis circuit further includes an antistatic protection diode unit, a first end e of the antistatic protection diode unit is connected to a second end d of the 302nd inductor L302, and the antistatic protection diode The second terminal f of the unit is connected to the second terminal b of the 301st inductor L301, and the third terminal g of the anti-static protection diode unit is grounded; the anti-static protection diode unit includes the 301st An antistatic protection diode D301 and a 302nd antistatic protection diode D302, one end of the 301st antistatic protection diode D301 is connected to a second end d of the 302nd inductor L302, the The other end of the 301st antistatic protection diode D301 is grounded; one end of the 302nd antistatic protection diode D302 is connected to the second end b of the 301st inductor L301, and the third The other end of the 102 antistatic protection diode D302 is grounded; the antistatic protection diode is used to protect the I / O ports in high-speed data transmission from overvoltage and antistatic protection, which improves the fault tolerance of the CAN analysis circuit;

9. The CAN analysis circuit further includes a filter circuit, and one end of the filter circuit is connected to the second terminal b of the 301st inductor L301 and the second terminal d of the 302nd inductor L302, respectively. The other end of the filter circuit is connected to the reference signal terminal 305 of the CAN transceiver; the filter circuit includes a 301st resistor R301, a 301st capacitor C301, and a 303st capacitor C303; A first capacitor plate of the third hundred and thirty-three capacitor C303 is connected to a reference signal terminal 305 of the CAN transceiver, and a second capacitor plate of the third hundred and thirty-three capacitor C303 is grounded; The two ends of the resistor R301 are respectively connected to the second terminal b of the 301st inductor L301 and the reference signal terminal 305 of the CAN transceiver; the first capacitor plate of the 301st capacitor C301 is connected to all The second terminal b of the 301st inductor L301 is connected, and the second capacitor plate of the 301st capacitor C301 is grounded; the filter circuit further includes a 302rd resistor R302 and a 302rd Capacitor C302, two ends of the third 302 resistor R302 and the third 302 inductor L are respectively The second terminal d of 302 is connected to the reference signal terminal 305 of the CAN transceiver; the first capacitor plate of the 302nd capacitor C302 is connected to the second terminal d of the 302nd inductor L302, The second capacitor plate of the 302nd capacitor C302 is grounded; a filter circuit is used to filter out the low-frequency interference signals during the high-speed signal transmission process, improve the signal transmission quality, and further improve the anti-interference ability of the CAN analysis circuit.

BRIEF DESCRIPTION OF THE DRAWINGS

1 is a schematic structural diagram of a vehicle-mounted intelligent terminal based on a Beidou navigation system of the present invention;

2 is a schematic structural diagram of a power management module according to the present invention;

3 is a circuit diagram of a DCDC power conversion circuit of the present invention;

4 is a circuit diagram of a first power conversion circuit of the present invention;

5 is a circuit diagram of a second power conversion circuit of the present invention;

6 is a circuit diagram of an automatic switching circuit of the present invention;

FIG. 7 is a circuit diagram of a CAN analysis circuit of the present invention.

detailed description

The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are part of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplified description, and does not indicate or imply that the device or element referred to must have a specific orientation, a specific orientation Construction and operation should therefore not be construed as limiting the invention. In addition, the terms "first," "second," and "third" are used for descriptive purposes only, and should not be construed to indicate or imply relative importance.

In the description of the present invention, it should be noted that the terms "installation", "connected", and "connected" should be understood in a broad sense unless otherwise specified and limited. For example, they may be fixed connections or removable. Connected or integrated; it can be mechanical or electrical; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.

As shown in FIG. 1, a vehicle-mounted intelligent terminal based on a Beidou navigation system includes a terminal power supply, a power management module, and a central controller. The terminal power supply, the power management module, and the central controller are sequentially powered through a power supply line. Connected, the central controller is electrically connected to the enable signal terminal of the power management module through a signal line; the power management module is connected to a motion sensing module, a Beidou navigation module, a Bluetooth module, a 4G module, and a CAN through a power line, respectively. The port module is electrically connected, and the motion sensing module, the Beidou navigation module, the Bluetooth module, the 4G module, and the CAN port module are electrically connected to the central controller through signal lines, respectively.

As shown in FIG. 2, the power management module includes a DCDC power conversion circuit, a first power conversion circuit, and a second power conversion circuit. A power input terminal of the DCDC power conversion circuit is electrically connected to the terminal power through a power supply line. The first power conversion circuit and the second power conversion circuit are respectively electrically connected to a conversion power output terminal of the DCDC power conversion circuit, and a driving current threshold of the first power conversion circuit is greater than the second power conversion circuit. The drive current threshold of the first conversion circuit is electrically connected to the 4G module of the wireless communication module through a power supply line, and the output end of the second power conversion circuit is respectively connected to the motion sensing module through a power supply line. The Beidou navigation module, the Bluetooth module of the wireless communication module, the central controller and the CAN port module are electrically connected.

As shown in FIG. 3, the DCDC power conversion circuit includes a DCDC power conversion chip, a power input terminal 1 of the DCDC power conversion chip is connected to the terminal power source, and an enable terminal 2 of the DCDC power conversion chip is connected to the terminal. The central controller is connected, the conversion output terminal 8 of the DCDC power conversion chip is connected to one end of the inductor L, and the other end of the inductance L is connected to the conversion power output terminal. The DCDC power conversion circuit further includes a first diode D1, a first resistor R1, and a first capacitor C1. The central controller is connected to a forward end of the first diode D1, and the first two The opposite end of the transistor D1 is connected to one end of the first resistor R1, the other end of the first resistor R1 is connected to the enable terminal 2 of the DCDC power conversion chip, and the first of the first capacitor C1 The capacitor plate is connected to a common connection point of the first resistor R1 and an enable terminal of the DCDC power conversion chip, and the second capacitor plate of the first capacitor C1 is grounded. The DCDC power conversion circuit further includes a second diode D2, a forward end of the second diode D2 is grounded, and a reverse end of the second diode D2 is converted by the DCDC power conversion chip. The output terminal 8 is connected to a common connection point of the inductor. The DCDC power conversion circuit further includes a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a second resistor R2, a third resistor R3, a fourth resistor R4, and a fifth resistor R5. The second resistor R2 and The third resistor R3 is connected in parallel, one end of the third resistor R3 is connected to the synchronization / restart terminal 3 of the DCDC power conversion chip, and the other end of the third resistor R3 is grounded; A capacitor plate is connected to the filter terminal 4 of the DCDC power conversion chip, the second capacitor plate of the second capacitor C2 is grounded; the fourth resistor R4 and the fifth resistor R5 are connected in series, and the fourth resistor R4 One end is connected to the output terminal of the conversion power supply, one end of the fifth resistor is grounded, and a common connection point of the fourth resistor R4 and the fifth resistor R5 is connected to the voltage stabilization terminal 7 of the DCDC power conversion chip. A first capacitor plate of the third capacitor is connected to the output terminal of the conversion power source, a second capacitor plate of the third capacitor is grounded, and the fourth capacitor is connected in parallel with the third capacitor. The DCDC power conversion circuit further includes a fifth capacitor C5, a sixth capacitor C6, and a seventh capacitor C7. The first capacitor plate of the fifth capacitor is connected to the startup terminal 9 of the DCDC power conversion chip. A second capacitor plate of the capacitor is connected to the conversion output terminal 8 of the DCDC power conversion chip and a common connection point of the inductor; a first capacitor plate of the sixth capacitor is connected to the terminal power supply and the DCDC power conversion chip. The common connection point of the power input terminal is connected, the second capacitor plate of the sixth capacitor is grounded, and the seventh capacitor is connected in parallel with the sixth capacitor; the ground terminal 6 and the digital-analog terminal 5 of the DCDC power conversion chip are both Ground.

As shown in FIG. 4, the first power conversion circuit includes a high-current power conversion chip, a power input terminal 10 of the high-current power conversion chip is connected to the conversion power output, and an output of the high-current power conversion chip The terminal 11 is connected to a first power consumption unit, the enable terminal 12 of the high-current power conversion chip is connected to one end of a sixth resistor R6, and the other end of the sixth resistor is connected to the central controller; A power conversion circuit further includes an eighth capacitor, a ninth capacitor, a tenth capacitor, a seventh resistor, and an eighth resistor. The first capacitor plate of the eighth capacitor and the power input terminal and the power source of the high-current power conversion chip. The common connection point of the output terminal of the conversion power supply is connected, the second capacitor plate of the eighth capacitor is grounded, the ninth capacitor is connected in parallel with the eighth capacitor, and the first capacitor plate of the tenth capacitor is connected to the high current. The output end of the power conversion chip is connected to a common connection point of the first power consumption unit, and the other end of the tenth capacitor is grounded; the seventh resistor and the eighth resistor are connected in series, and the seventh resistor The terminal is connected to the output terminal of the high-current power conversion chip and a common connection point of the first power consumption unit, one end of the eighth resistor is grounded, and the regulating terminal 13 of the high-current power conversion chip is connected to the first The seventh resistor is connected to the common connection point of the eighth resistor; the ground terminal of the high-current power conversion chip is grounded.

As shown in FIG. 5, the second power conversion circuit includes a low-current power conversion chip, a power input terminal 14 of the small-current power conversion chip is connected to the conversion power output, and an output of the small-current power conversion chip Terminal 15 is connected to the second power consumption unit; the second power conversion circuit further includes an eleventh capacitor C11, a twelfth capacitor C12, and a thirteenth capacitor C13, and a first capacitor plate of the eleventh capacitor Is connected to a common connection point between the power input terminal of the small-current power conversion chip and the output terminal of the conversion power, and the second capacitor plate of the eleventh capacitor is grounded; the twelfth capacitor and the eleventh capacitor Connected in parallel; the first capacitor plate of the thirteenth capacitor is connected to the common connection point of the output terminal of the small current power conversion chip and the second power consumption unit, and the second capacitor plate of the thirteenth capacitor is grounded The ground terminal 16 of the small-current power conversion chip is grounded.

In the vehicle-mounted intelligent terminal based on the Beidou navigation system described in this embodiment, when the central controller does not output an enable signal, only the DCDC power conversion circuit in the power management module is charged, and the static current of the entire circuit and the DCDC power conversion circuit are The quiescent current is basically the same, because the quiescent current of the DCDC power conversion circuit is very small, which can fully meet the requirements of the vehicle terminal controller for the quiescent current, and solves the problem of relatively high static power consumption of the controller; when the central controller output is enabled When the signal is sent, the DCDC power conversion circuit starts to work, and the first power conversion circuit, the second power conversion circuit, and the fifth power conversion circuit in the power management module start to work. Due to the very high switching frequency of the DCDC power conversion chip, its power conversion The efficiency is also very high. Even if the power conversion efficiency of the first power conversion circuit, the second power conversion circuit, and the fifth power conversion circuit is relatively low, the overall efficiency can reach the optimal balance, which can ensure the interference of the application components on the ripple. Saved costs again.

In the vehicle-mounted intelligent terminal based on the Beidou navigation system in this embodiment, the first power conversion circuit includes a high-current power conversion chip, and the power input terminal 10 of the high-current power conversion chip is connected to the conversion power output terminal. An output terminal 11 of the high-current power conversion chip is connected to a first power consumption unit, an enable terminal 12 of the high-current power conversion chip is connected to one end of a sixth resistor R6, and the other end of the sixth resistor is connected to all The central controller is connected; through the central controller's enabling control of the high-current power conversion chip, the ripple of the first power consumption unit is further reduced, and the problem that some components are sensitive to the ripple of the power is solved .

In the vehicle-mounted intelligent terminal based on the Beidou navigation system in this embodiment, the high-current power conversion chip, the low-current power conversion chip, and the second low-current power conversion chip all use automotive-grade power chips, which solves the terminal problem. Power management stability issues.

The model of the backup power supply in this embodiment may be HSC-1000, the Beidou navigation module may be an HX-BS498A receiver, the central controller may be a TD-D302 chip, and the model of the wireless communication module may be MS0SFA, a model of the motion sensing module. The model can be XYK-BMJ-38Z6-V.

In the embodiment of the vehicle-mounted intelligent terminal based on the Beidou navigation system, the high-current power conversion chip, the low-current power conversion chip, and the second low-current power conversion chip all adopt an LDO (low dropout regulator), which is a Low-dropout linear regulator) automotive grade chip; the model of the high-current power conversion chip is MIC35302, whose output voltage is 3.8V; the model of the low-current power conversion chip is LM1117-3.3, whose output voltage is 3.3 V; the model of the second small-current power conversion chip is LM1117-1.8, and its output voltage is 1.8V; the model of the DCDC power conversion chip is MR14050, and its output voltage is 5V.

In the embodiment of the vehicle-mounted intelligent terminal based on the Beidou navigation system, the design of the power management mainly considers two aspects, one is to ensure that the static power consumption of the controller is very low, and the other is to ensure that the controller uses electricity during normal operation. Very efficient. According to the design standards for the static power consumption of the entire vehicle, each controller must enter the sleep or ultra-low power consumption mode when it is not working, which can ensure the service life of the vehicle's 12V low-voltage battery. Considering that the current low-voltage controller of pure electric new energy vehicles comes from the high-voltage battery pack, and the power of the high-voltage battery pack is certain, so when designing each controller on a pure electric new-energy vehicle, the controller must be guaranteed. Power efficiency issues during normal work. When the system was designed, in addition to pursuing two main design ideas, it also designed the cost and application environment. This system contains a high-efficiency DCDC power conversion chip, while taking into account a stable LDO power conversion chip, to ensure the system's balance in efficiency and cost.

The vehicle-mounted intelligent terminal based on the Beidou navigation system described in this embodiment, the DCDC power conversion chip is the controller's vehicle main power chip, which provides the power consumption output of the entire controller, an ultra-low working quiescent current of 40UA, and a switching frequency of up to 2.5MHZ. Equipped with enable pin for easy control; high-current LDO power conversion chip: current output capability up to 3A, ripple is very small, very suitable for powering the first power-sensitive unit that is sensitive to ripple; medium-current LDO power conversion chip and small current LDO power conversion chip: small ripple, low price, simple peripheral circuit design, suitable for supplying power to the second power unit and the fifth power unit.

The working process of the power management module of the vehicle-mounted intelligent terminal based on the Beidou navigation system in this embodiment is as follows: 1) When the enable signal is not available, only the DCDC power conversion chip in the entire circuit is charged. Due to the static state of the power chip The current is only 40UA, so the static current of the entire terminal controller (the sum of the static current of the terminal power supply and the static current of the DCDC power conversion chip) is only more than 40UA, which can fully meet the requirements of the vehicle controller for static current; 2) When the enable signal is present, the DCDC power conversion chip starts to work, and the entire circuit starts to work. Because the switching frequency of the DCDC power conversion chip is up to 2.5MHZ, its power conversion efficiency is as high as 97%; 3) The second-level LDO power conversion chip (including The high-current power conversion chip, the low-current power conversion chip, and the second low-current power conversion chip) have low power conversion efficiency, and the overall efficiency can reach 70%, but considering the cost and the third-level application element Device usage scenarios, using LDO can not only guarantee the interference of third-level application components to the ripple, but also save Cost, this can achieve optimal equilibrium.

Referring to FIG. 6, the automatic switching circuit includes a 203 transistor, a 203 transistor, and a 203 transistor; The first output terminal is connected to the power output terminal, and the second output terminal of the 203 transistor is connected to the first output terminal of the 203 transistor, and the 201 A 201 resistor is connected between the input terminal of the transistor and the second output terminal of the 201 transistor; the power output terminal and the power input terminal of the DCDC power conversion circuit are electrically connected. Connected; the input terminal of the 203 transistor is connected to the first output terminal of the 203 transistor, and the second output terminal of the 203 transistor is grounded, A 205 resistor is connected between the input terminal of the 203 transistor and the second output terminal of the 203 transistor; the 203 transistor The second output terminal of the transistor is grounded, and the second output terminal of the second transistor is connected to the second output terminal of the second transistor. Resistance; a standby power supply is connected in series between the input terminal of the 203 transistor and the first output terminal of the 203 transistor; the first of the 203 transistor An on-board main power supply is connected in series between an output terminal and an input terminal of the 203 transistor.

In the vehicle-mounted intelligent terminal based on the Beidou navigation system in this embodiment, the automatic switching circuit further includes a 200th diode D200, a first output terminal of the 201st transistor Q201 and the first The reverse end of the two hundred diode D200 is connected, and the forward end of the two hundred diode is connected to the vehicle main power supply; it further includes a second resistor R203, and the second resistor 203 A first output terminal of the transistor Q203 is connected to one end of the second hundred and thirty-three resistor R203, and the other end of the second one hundred and thirty-three resistor R203 is connected to the backup power source. It also includes a 206th resistor R206, an input end of the 203th transistor Q203 is connected to one end of the 206th resistor R206, and the other end of the 206th resistor R206 It is connected with the vehicle main power supply. It also includes a second resistor R202, the second output terminal of the second transistor Q201 is connected to one end of the second resistor R202, and the second resistor R202 The other end is connected to the first output end of the 20220 transistor Q202. It also includes a 204th resistor R204, the input terminal of the 202104 transistor R202 is connected to one end of the 204 resistor R204, and the other end of the 204 resistor R204 It is connected to the first output terminal of the second transistor Q203. It also includes a 201st capacitor C201, a 202nd capacitor C202, and a 203rd capacitor C203. The first capacitor plate of the 203rd capacitor C203 and the 206th resistor R206 Connected to the common connection point of the 207th resistor R207, the second capacitor plate of the 203th capacitor C203 is grounded; the first capacitor plate of the 201st capacitor C201 is connected to the first capacitor plate The first output terminal of the 201 transistor Q201 is connected, and the second capacitor plate of the 201 capacitor C201 is grounded; the 202 capacitor C202 and the 201 capacitor C201 in parallel.

The vehicle-mounted intelligent terminal based on the Beidou navigation system disclosed by the present invention passes through an automatic switching circuit composed of the 201st transistor Q201, the 20023 transistor Q202, and the 2003 transistor Q203, Realize the seamless switching of the power supply of the power output end of the power supply for the vehicle communication device between the backup power source and the vehicle main power supply, and solve the problem of uninterrupted power supply of the vehicle communication device and the problem of switching between the two power supply systems. No MCU such as a microcontroller Control, realize automatic switching according to different external conditions, simple circuit structure, smart design, low cost, stable performance, and can be fine-tuned according to different environments.

In the vehicle-mounted intelligent terminal based on the Beidou navigation system disclosed in the present invention, a first output terminal of the 201st transistor Q201 is connected to a vehicle main power supply through a 200th diode D200, and the 200th The first output terminal of the triode Q203 is connected to the backup power source through the 203 resistor R203, and the input terminal of the 203 transistor Q203 is connected to the main vehicle power supply through the 206 resistor R6. A second output terminal of the 201 transistor Q201 is connected to a first output terminal of the 202 transistor Q202 through a 202 resistor R202; The input terminal of the second transistor Q202 is connected to the first output terminal of the second transistor Q203 through the second 204 resistor R204; the power supply can be switched by setting a plurality of different voltage dividing resistors The speed is regulated to realize the controllability of the circuit.

The vehicle-mounted intelligent terminal based on the Beidou navigation system disclosed in the present invention, the automatic switching circuit further includes a 201st capacitor C201, a 202nd capacitor C202, and a 203rd capacitor C203. A first capacitor plate of the zero-three capacitor C203 is connected to a common connection point of the second and sixth resistors R206 and 207, and a second capacitor plate of the second and third capacitor C203 is grounded. The first capacitor plate of the 201st capacitor C201 is connected to the first output terminal of the 201 transistor Q201, and the second capacitor plate of the 201st capacitor C201 is grounded; The 202nd capacitor C202 is connected in parallel with the 201st capacitor C201; by setting a buffer capacitor, during the switching of the power supply, it plays a buffer effect on the voltage drop and rise, reducing the impact on the circuit To improve the stability and reliability of the circuit.

The vehicle-mounted intelligent terminal based on the Beidou navigation system disclosed in the present invention is suitable for a vehicle-mounted controller that has two sets of power supply systems and requires automatic seamless switching. By using capacitors, resistors, diodes, and triodes (the full name should be semiconductor triodes, also It is called bipolar transistor, transistor (hereinafter referred to as triode)) and metal-oxide semiconductor field effect transistor, referred to as metal-oxide-semiconductor field effect transistor (hereinafter referred to as MOSFET) to build a set of efficient and stable switching circuit system.

The vehicle-mounted intelligent terminal based on the Beidou navigation system disclosed in the present invention, a triode is a semiconductor device that controls current, and its function is to amplify a weak signal into an electric signal with a large amplitude value, and it is also used as a non-contact switch. There are two types of materials: germanium tubes and silicon tubes. Each of them has two structural forms of NPN and PNP, but the most commonly used are silicon NPN and germanium PNP triodes, (where N is the meaning of the negative electrode (negative in English), and N-type semiconductors are used in high-purity silicon. Adding phosphorus to replace some silicon atoms will generate free electron conduction under voltage stimulation, and P means positive (Positive) means adding boron instead of silicon to generate a large number of holes to facilitate conduction). MOSFET is a field-effect transistor that can be widely used in analog circuits and digital circuits. MOSFETs can be divided into "N" and "P" types according to the polarity of their "channels" (working carriers). They are also commonly called NMOSFETs and PMOSFETs. Other short names include NMOS, PMOS, etc. .

The vehicle-mounted intelligent terminal based on the Beidou navigation system disclosed in the present invention has a buffer function for voltage drop and rise; resistance: a combination of different resistors to build different voltage shunts; triode: N-type triode is used in this system , Using the high-speed switching performance of N-type transistor; MOSFET: This system uses P-channel enhanced MOSFET (PMOS for short), using its conductivity: a positive voltage UGS is applied between the gate and source, the gate is insulated to achieve the drain It is conductive with the source; diode: the function of diode forward conduction and reverse cutoff is selected.

As shown in FIG. 7, the CAN analysis circuit includes a CAN transceiver and a common-mode inductor; the CAN transceiver is provided with a transmitting end 301 for sending a CAN parameter signal to a central controller, and is used for receiving a signal from the central processor. A receiving end 304 of a control signal; a high-voltage end 307 and a low-voltage end 306 are also provided; the common-mode inductor includes a 301st inductor L301 and a 302nd inductor L302 in a common-mode induction setting; Wherein, a first terminal a of the 301st inductor L301 is connected to the high-voltage terminal 307, and a second terminal b of the 301st inductor L301 is used for connection with a high-voltage signal line of a CAN bus; A first terminal c of the 302nd inductor L302 is connected to the low voltage terminal 306, and a second terminal d of the 302nd inductor L302 is used for connection with a low-voltage signal line of the CAN bus.

The vehicle-mounted intelligent terminal based on the Beidou navigation system disclosed in the present invention uses a common-mode inductor to filter common-mode electromagnetic interference signals by setting a CAN transceiver and a common-mode inductor, and simultaneously plays the role of EMI filtering to suppress high-speed signal lines. The generated electromagnetic waves are radiated to the outside, which improves the anti-interference ability of the CAN analysis circuit and ensures the reliability of the signal in high-speed transmission.

Referring to FIG. 7, the CAN analysis circuit further includes an anti-static protection diode unit. A first terminal e of the anti-static protection diode unit is connected to a second terminal d of the 302nd inductor L302. The second terminal f of the antistatic protection diode unit is connected to the second terminal b of the 301st inductor L301, and the third terminal g of the antistatic protection diode unit is grounded. The antistatic protection diode unit includes a 301st antistatic protection diode D301 and a 302th antistatic protection diode D302. One end of the 301st antistatic protection diode D301 is connected to the third hundredth. The second end d of the zero-two inductance L302 is connected, and the other end of the third 301 antistatic protection diode D301 is grounded; one end of the third 302 anti-static protection diode D302 is connected to the third one The second end b of the inductor L301 is connected, and the other end of the 302 antistatic protection diode D302 is grounded; the antistatic protection diode is used to perform overvoltage and antistatic protection on the I / O port in high-speed data transmission, so as to improve The fault-tolerant ability of CAN analysis circuit is introduced.

As shown in FIG. 7, the CAN analysis circuit further includes a filter circuit. One end of the filter circuit is connected to the second terminal b of the third hundred and first inductor L301 and the second one of the third and second inductor L302. The second terminal d is connected, and the other end of the filter circuit is connected to the reference signal terminal 305 of the CAN transceiver; the filter circuit includes a 301st resistor R301, a 301st capacitor C301, and a 300th resistor. The zero-three capacitor C303; the first capacitance plate of the third-three-three-three capacitor C303 is connected to the reference signal terminal 305 of the CAN transceiver, and the second capacitance plate of the three-three-three-th capacitor C303 is grounded; The two ends of the 301st resistor R301 are respectively connected to the second terminal b of the 301st inductor L301 and the reference signal terminal 305 of the CAN transceiver; A capacitor plate is connected to the second terminal b of the 301st inductor L301, and the second capacitor plate of the 301st capacitor C301 is grounded; the filter circuit further includes a 302rd resistor R302 and The 302th capacitor C302, the two ends of the 302th resistor R302 are respectively connected to the first The second terminal d of the one hundred and twenty-two inductor L302 is connected to the reference signal terminal 305 of the CAN transceiver; the first capacitor plate of the third one hundred and twenty-two capacitor C302 and the second one of the three hundred and twenty-two inductor L302 Terminal d is connected, and the second capacitor plate of the 302nd capacitor C302 is grounded; the filter circuit is used to filter out low-frequency interference signals during high-speed signal transmission, improve the signal transmission quality, and further improve the anti-interference of the CAN analysis circuit. ability.

As shown in FIG. 7, the CAN analysis circuit further includes a third resistor R303. The interference signal output terminal 308 of the CAN transceiver is connected to one end of the third resistor R303. The other end of the 3003 resistor R303 is grounded. The CAN analysis circuit further includes a 304 capacitor C304, the power input terminal 303 of the CAN transceiver and the power supply (ie, the conversion power output terminal of the DCDC power conversion circuit, see VCC) and the third The first capacitor plate of the one hundred and four capacitor C304 is connected, the second capacitor plate of the third one hundred and four capacitor C304 is grounded, and the ground terminal 302 of the CAN transceiver is grounded. The model of the CAN transceiver is TJA1042. The common mode inductor is a common mode inductor of model T181007-8MH from Shenzhen Beyout Technology Co., Ltd .; the ESD protection diode is an ESD of Shenzhen Chengqianshun Electronics Co., Ltd. as BESDL0402-12. Static protection diode.

The vehicle-mounted intelligent terminal based on the Beidou navigation system disclosed in the present invention, a CAN transceiver (sometimes also referred to as a driver) is a physical layer of the CAN bus, and is used to convert a binary code stream into a differential signal and send the differential signal into a binary code. Stream reception. Common mode choke, also known as common mode choke, is commonly used in computer switching power supplies to filter common mode electromagnetic interference signals. In the board design, the common mode inductor also plays the role of EMI filtering, which is used to suppress the electromagnetic radiation generated by high-speed signal lines from radiating outward. Anti-static protection diode is an over-voltage and anti-static protection element, which is a device designed for I / O port protection of high-speed data transmission applications. ESD protection devices are used to prevent sensitive circuits in electronic equipment from being affected by ESD (electrostatic discharge).

The vehicle-mounted intelligent terminal based on the Beidou navigation system disclosed in the present invention, TJA1042 is a new transceiver from NXP, which is specially designed for high-speed CAN applications, with a transmission speed of up to 1MB / second. During the development process, it cooperates with major automotive manufacturers to make The new product has extremely low electromagnetic radiation (EME) characteristics, and has stronger protection against excitation effects. The above-mentioned features can ensure the reliability of communication even for the current most advanced networks where the number of ECUs is increasing and the bus topology continues to be complicated. The common-mode inductor must filter common-mode electromagnetic interference on the signal line on the one hand, and on the other hand The suppression itself does not emit electromagnetic interference to avoid affecting the normal operation of other electronic equipment in the same electromagnetic environment. The ESD electrostatic protection diode is connected in parallel to the circuit. When the circuit works normally, it is in the cut-off state (high-impedance state), which does not affect the normal operation of the line. When the circuit has an abnormal overvoltage and reaches its breakdown voltage, it quickly changes from a high resistance The state changes to a low-impedance state, providing a low-impedance conduction path for instantaneous currents, while clamping the abnormal high voltage within a safe level, thereby protecting the protected IC or line; when the abnormal overvoltage disappears, it returns to a high-impedance state, and the circuit normal work.

The working process of the CAN analysis circuit in this embodiment is: 1) When the circuit starts to work, the data is transmitted at a speed of up to 500KB / S, which causes external radiation interference. At the same time, external interference can easily affect high-speed signals. 2) At this time, common-mode inductors are required to process high-speed information to minimize external radiation interference and at the same time reverse external interference; 3) When the circuit is applied to an external interface, the controller is plugged and unplugged During the process, it is very easy to form static electricity. ESD protection devices can be used to reverse the static electricity. ESD devices have very low junction capacitance without affecting the accuracy of high-speed signals. 4) By controlling the resistance of the resistor, you can Realize the flexible use of this circuit in CAN network.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, but not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or to replace some or all of the technical features equivalently; and these modifications or replacements do not depart from the essence of the corresponding technical solutions of the technical solutions of the embodiments of the present invention. range.

Claims

A vehicle-mounted intelligent terminal based on a Beidou navigation system is characterized in that it includes a terminal power supply with the function of automatically switching the vehicle's main power supply and backup power supply, a power management module with high-efficiency power conversion efficiency, and a central controller. The power management module and the central controller are electrically connected in sequence through a power supply line, and the central controller is electrically connected to an enable signal end of the power management module through a signal line; the power management module is separately connected to the motion through a power supply line. The sensing module, Beidou navigation module, wireless communication module and CAN port module with analysis function are electrically connected. The motion sensing module, the Beidou navigation module, the wireless communication module and the CAN port module are respectively connected by signal lines. It is electrically connected to the central controller.
The vehicle-mounted intelligent terminal based on the Beidou navigation system according to claim 1, wherein the power management module comprises a DCDC power conversion circuit, a first power conversion circuit and a second power conversion circuit, and the DCDC power conversion circuit The power input terminal is electrically connected to the terminal power supply through a power supply line, and the first power conversion circuit and the second power conversion circuit are electrically connected to a conversion power output terminal of the DCDC power conversion circuit, respectively, and the first power supply The driving current threshold of the conversion circuit is greater than the driving current threshold of the second power conversion circuit; the output of the first conversion circuit is electrically connected to the 4G module of the wireless communication module through a power supply line, and the second power conversion circuit The output end is electrically connected to the motion sensing module, the Beidou navigation module, the Bluetooth module of the wireless communication module, the central controller and the CAN port module through a power supply line.
The vehicle-mounted intelligent terminal based on the Beidou navigation system according to claim 2, characterized in that: the DCDC power conversion circuit is a DCDC power conversion chip, and a power input terminal of the DCDC power conversion chip is connected to the terminal power, and An enable terminal of the DCDC power conversion chip is connected to the central controller, a conversion output terminal of the DCDC power conversion chip is connected to one end of an inductor, and the other end of the inductor L is connected to the conversion power output terminal.
The vehicle-mounted intelligent terminal based on the Beidou navigation system according to claim 3, wherein the first power conversion circuit comprises a high-current power conversion chip, a power input terminal of the high-current power conversion chip and the conversion power The output end is connected, the output end of the high-current power conversion chip is connected to the 4G module of the wireless communication module, the enable end of the high-current power conversion chip is connected to one end of a sixth resistor, The other end is connected to the central controller.
The vehicle-mounted intelligent terminal based on the Beidou navigation system according to claim 4, wherein the second power conversion circuit comprises a low-current power conversion chip, a power input terminal of the small-current power conversion chip and the conversion power The output end is connected, and the output end of the low-current power conversion chip is respectively connected to the motion sensing module, the Beidou navigation module, the wireless communication module's Bluetooth module, the central controller, and the CAN through a power supply line. The port module is electrically connected.
The vehicle-mounted intelligent terminal based on the Beidou navigation system according to claim 1, wherein the terminal power supply comprises a vehicle main power supply, a backup power supply and an automatic switching circuit, and the vehicle main power supply and the backup power supply are respectively provided through a power supply line. It is electrically connected to the automatic switching circuit, and an output terminal of the automatic switching circuit is electrically connected to a power input terminal of the DCDC power conversion circuit through a power supply line.
The vehicle-mounted intelligent terminal based on the Beidou navigation system according to claim 6, wherein the automatic switching circuit comprises a 203 transistor, a 203 transistor, and a 203 transistor Pole tube

The first output terminal of the two hundred and three transistor is connected to the power output terminal, and the second output terminal of the two hundred and three transistor is connected to the first one of the two hundred twenty three transistor. The output terminal is connected, and a 201 resistance is connected between the input terminal of the 203 transistor and the second output terminal of the 211 transistor; the power output terminal is connected to The power input terminal of the DCDC power conversion circuit is electrically connected;

The input terminal of the second transistor is connected to the first output terminal of the second transistor, and the second output terminal of the second transistor is grounded. A 205 resistor is connected between the input terminal of the 203 transistor and the second output terminal of the 203 transistor;

A second output terminal of the 203 triode is grounded, and an input terminal of the 203 triode is connected to a second output terminal of the 203 triode. 207 resistance

A backup power source is connected in series between the input terminal of the 203 transistor and the first output terminal of the 203 transistor; the first output terminal of the 203 transistor And the main terminal of the vehicle is connected in series with the input terminal of the 203 triode.
The vehicle-mounted intelligent terminal based on the Beidou navigation system according to claim 1, wherein the CAN port module includes a CAN analysis circuit, and the CAN analysis circuit is connected to an output terminal of the second power conversion circuit through a power supply line. Connection, the CAN analysis circuit is electrically connected to the central controller through a signal line.
The vehicle-mounted intelligent terminal based on the Beidou navigation system according to claim 8, wherein the CAN analysis circuit comprises a CAN transceiver and a common mode inductor;

The CAN transceiver is provided with a transmitting end for sending a CAN parameter signal to the central controller and a receiving end for receiving a control signal sent from the central processor; and a high voltage end and a low voltage end are also provided;

The common mode inductor includes a 301st inductor and a 302nd inductor in a common mode induction setting, wherein a first terminal of the 301st inductor is connected to the high voltage terminal, so The second end of the 301st inductor is used for connection with a high-voltage signal line of the CAN bus; the first end of the 302nd inductor is connected to the low voltage end, and the 302nd inductor The second end is used to connect with the low-voltage signal line of the CAN bus.
The vehicle-mounted intelligent terminal based on the Beidou navigation system according to claim 9, wherein the CAN analysis circuit further comprises an anti-static protection diode unit, a first end of the anti-static protection diode unit and the third hundredth The second terminal of the zero-second inductor is connected, the second terminal of the anti-static protection diode unit is connected to the second terminal of the 301st inductor, and the third terminal of the anti-static protection diode unit is grounded.