A vehicle air conditioner controller

Abstract

The utility model discloses a kind of vehicle air conditioner controller, including key control circuit, control output circuit, sensor acquisition circuit, nixie tube display drive circuit, LED lamp drive circuit, single-chip microcontroller, power supply circuit, still further contain voltage acquisition circuit, low voltage detection circuit and buzzer drive circuit, each module works cooperatively to realize the accurate control and state monitoring of vehicle air conditioner.Each module cooperates to realize the state detection and accurate control of vehicle air conditioner system, and through modularization and integration design, the anti-interference ability is enhanced while guaranteeing high performance.Solve the problem of low circuit integration of traditional discrete device, the problem of insufficient control output precision, achieve the purpose of improving the problem of vehicle air conditioner system, reliability and user experience.

Description

Technical Field

[0001] This utility model relates to the field of air conditioning control technology, and in particular to a vehicle air conditioning controller. Background Technology

[0002] Against the backdrop of rapid development in the automotive industry, automotive air conditioning controllers, as core components for regulating the in-vehicle environment, directly impact driving comfort and system reliability. Existing automotive air conditioning controllers still have many shortcomings in practical applications. For example, some controllers lack sufficient control output accuracy, actuator drives lack reliable protection, and components are easily damaged by current and voltage fluctuations; moreover, many lack comprehensive voltage monitoring and fault indication functions, making troubleshooting inconvenient. These problems restrict the reliability of automotive air conditioning and user experience, necessitating more optimized controller solutions.

[0003] Therefore, this utility model provides a new solution to this problem. Utility Model Content

[0004] In view of the above situation and to overcome the defects of the prior art, the purpose of this utility model is to provide a vehicle air conditioning controller.

[0005] The technical solution is: a vehicle air conditioning controller, comprising:

[0006] The button control circuit is used to receive the user's button commands and transmit the commands to the microcontroller;

[0007] The control output circuit is used to control the working status of the compressor clutch, evaporator fan and heating actuator according to the instructions of the microcontroller;

[0008] The sensor acquisition circuit is connected to the return air vent temperature sensor and the defrost temperature sensor respectively, and is connected to the microcontroller. It is used to acquire the vehicle interior temperature signal and the defrost temperature signal and transmit them to the microcontroller.

[0009] The digital tube display driver circuit is connected to the microcontroller and is used to drive the digital tube to display the set temperature, the interior temperature, the defrost temperature and the fault code.

[0010] The LED light driving circuit is connected to the microcontroller and is used to drive the air volume indicator, compressor working indicator and heating working indicator to turn on or off or flash.

[0011] The microcontroller is used to receive and process signals transmitted by various circuits and output control commands.

[0012] The power supply circuit is used to convert the externally input DC28V voltage into a voltage suitable for the microcontroller and driving various circuits.

[0013] Preferably, the control output circuit includes at least one BTS724G high-side power switch and at least one BTS4141N high-side power switch. The input terminal of the BTS724G is connected to the I / O port of the microcontroller, and the output terminal is connected to the control terminal of the compressor clutch and the evaporator fan. The input terminal of the BTS4141N is connected to the I / O port of the microcontroller, and the output terminal is connected to the control terminal of the heating actuator.

[0014] Preferably, the sensor acquisition circuit includes a first voltage divider circuit and a second voltage divider circuit. The first voltage divider circuit is composed of the return air vent temperature sensor and a first fixed resistor connected in series. The second voltage divider circuit is composed of the defrost temperature sensor and a second fixed resistor connected in series. The output terminals of the first voltage divider circuit and the second voltage divider circuit are respectively connected to the I / O port of the microcontroller.

[0015] Preferably, the digital tube display driver circuit includes a 74HC164 serial input parallel output shift register. The CLK and DATA terminals of the 74HC164 are respectively connected to the I / O ports of the microcontroller. The output terminal is connected to the segment selection terminal of the two-digit common cathode digital tube through a current-limiting resistor. The digit selection terminal of the digital tube is connected to the I / O port of the microcontroller through a transistor driver circuit.

[0016] Preferably, the LED driving circuit includes a first transistor, the base of the first transistor is connected to the I / O port of the microcontroller through a first resistor, the emitter of the first transistor is grounded, and the collector of the first transistor is connected to the power supply control terminals of the fan speed indicator, the compressor working indicator and the heating working indicator through a second resistor.

[0017] Preferably, the microcontroller uses the KF8A100ETN chip.

[0018] Preferably, the buttons include an airflow adjustment button, an A / C control button, a temperature setting up button, a temperature setting down button, and a heating button.

[0019] Preferably, the vehicle air conditioning controller further includes a voltage acquisition circuit, which is used to acquire the output voltage of the power supply circuit and transmit the acquired voltage signal to the microcontroller.

[0020] Preferably, the vehicle air conditioning controller further includes a low-voltage detection circuit, which includes an optocoupler. The input terminal of the optocoupler has a light-emitting diode connected in series with a voltage divider resistor and a diode. One end of the voltage divider resistor is connected to the VOLTAGE power supply terminal of the power supply circuit, and the other end is connected to the anode of the light-emitting diode of the optocoupler. The cathode of the light-emitting diode of the optocoupler is connected to the PRESS_IN detection port through the diode. The collector of the transistor at the output terminal of the optocoupler is connected to the VCC power supply terminal of the power supply circuit, and the emitter is grounded through a pull-down resistor. The detection signal terminal of the emitter is connected to the I / O port of the microcontroller.

[0021] Preferably, the vehicle air conditioning controller further includes a buzzer driving circuit, which includes a second transistor and a speaker. The base of the second transistor is connected to the SPEAKER_CTRL control terminal of the microcontroller through a current-limiting resistor. The emitter of the second transistor is grounded, the collector of the second transistor is connected to the negative terminal of the speaker, and the positive terminal of the speaker is connected to the VCC power supply terminal of the power supply circuit.

[0022] Through the above technical solutions, the beneficial effects of this utility model are as follows: The vehicle air conditioning controller of this application, by adopting a KF8A100ETN microcontroller as the core control unit, combined with sensor acquisition circuits, digital tube display driving circuits, voltage acquisition circuits, low-voltage detection circuits, and buzzer driving circuits, achieves precise control and comprehensive status monitoring of the in-vehicle environment. Through optimized layout and integrated design, each circuit module enhances anti-interference capabilities while ensuring high performance, solving the problems of low integration and insufficient control output accuracy in traditional discrete component circuits, and comprehensively improving the stability, reliability, and user experience of the vehicle air conditioning system. Attached Figure Description

[0023] Figure 1 This is a system module structure diagram of the present invention.

[0024] Figure 2 This is a schematic diagram of a button control circuit according to an embodiment of the present invention.

[0025] Figure 3 This is a schematic diagram of the control output circuit according to an embodiment of the present invention.

[0026] Figure 4 This is a schematic diagram of a sensor acquisition circuit according to an embodiment of the present invention.

[0027] Figure 5 This is a schematic diagram of a digital tube display driving circuit according to an embodiment of the present invention.

[0028] Figure 6 This is a schematic diagram of a transistor driving circuit according to an embodiment of the present invention.

[0029] Figure 7 This is a schematic diagram of an LED lamp driving circuit according to an embodiment of the present invention.

[0030] Figure 8 This is a wiring diagram of the microcontroller I / O port according to an embodiment of the present invention.

[0031] Figure 9 This is a schematic diagram of the power supply circuit according to an embodiment of the present invention.

[0032] Figure 10 This is a schematic diagram of a voltage acquisition circuit according to an embodiment of the present invention.

[0033] Figure 11 This is a schematic diagram of a low-voltage detection circuit according to an embodiment of the present invention.

[0034] Figure 12 This is a schematic diagram of a buzzer driver circuit according to an embodiment of the present invention. Detailed Implementation

[0035] The foregoing and other technical contents, features and effects of this utility model are described in conjunction with the appendix below. Figure 1 To be continued Figure 12 The detailed description of the embodiments will make this clear. All structural details mentioned in the following embodiments are based on the accompanying drawings.

[0036] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings.

[0037] like Figure 1 As shown, a vehicle air conditioning controller includes a button control circuit, a control output circuit, a sensor acquisition circuit, a digital tube display driver circuit, an LED light driver circuit, a microcontroller, and a power supply circuit. It further includes a voltage acquisition circuit, a low-voltage detection circuit, and a buzzer driver circuit. All modules work together to achieve precise control and status monitoring of the vehicle air conditioning.

[0038] like Figure 2 and 3As shown, the button control circuit receives user operation commands, including buttons for fan speed adjustment, A / C control, temperature setting up, temperature setting down, and heating. These commands are transmitted to the microcontroller for processing. The control output circuit, as the core module for execution control, employs at least one BTS724G high-side power switch and at least one BTS4141N high-side power switch. The input of the BTS724G is connected to the microcontroller's I / O port, and its output is connected to the control terminals of the compressor clutch and evaporator fan. The input of the BTS4141N is connected to the microcontroller's I / O ports P2.2 to P2.5, and its output is connected to the control terminal of the heating actuator, thereby controlling the operating status of these actuators according to the microcontroller's commands.

[0039] The sensor acquisition circuit is responsible for acquiring the temperature signal and consists of a first voltage divider circuit and a second voltage divider circuit, such as... Figure 4 As shown, the first voltage divider circuit is connected in series with the return air vent temperature sensor and the first fixed resistor R3, and the second voltage divider circuit is connected in series with the defrost temperature sensor and the second fixed resistor R5. The output terminals of the two voltage divider circuits are connected to the I / O ports P2.0 and P2.1 of the microcontroller, respectively, to transmit the collected in-vehicle temperature signal and defrost temperature signal to the microcontroller.

[0040] like Figure 5 As shown, the digital tube display driver circuit uses a 74HC164 serial input parallel output shift register. Its CLK and DATA terminals are connected to the microcontroller's I / O ports P1.4 and P1.5, respectively. The output terminal is connected to the segment selection terminals Q0 to Q7 of the two common cathode digital tubes through a current-limiting resistor. The digit selection terminals of the digital tubes are connected to the microcontroller's I / O ports P1.7 and P3.1 through a transistor driver circuit. This circuit is used to display the set temperature, interior temperature, defrost temperature, and fault codes.

[0041] Specifically, in this embodiment, there are two transistor driving circuits, such as... Figure 6 As shown, the DIG_CTRL1-1 and DIG_CTRL1-2 terminals are used to drive the digital tube. Specifically, in the transistor driver circuit, the bases of transistors Q6 and Q7 are connected to the microcontroller's I / O port through current-limiting resistors, and the collectors of transistors Q6 and Q7 are connected to the DIG_CTRL1-1 and DIG_CTRL1-2 terminals through current-limiting resistors.

[0042] like Figure 7As shown, the LED light driving circuit includes a first transistor Q8. The base of the transistor is connected to the I / O port P1.6 of the microcontroller through a first resistor R24, the emitter is grounded, and the collector is connected to the power supply control terminals of the high / medium / low airflow indicator, the compressor working indicator, and the heating working indicator through a second resistor R26, thereby driving the indicator lights to turn on or off or flash, providing feedback on the operating status of the air conditioner.

[0043] The microcontroller, serving as the control core, uses the KF8A100ETN chip. It receives signals transmitted from various circuits, processes them, and outputs corresponding control commands to coordinate the operation of each module. For example... Figure 8 As shown, this chip is based on the ARM Cortex-M0+ core architecture, featuring low power consumption and high performance. Its operating frequency can reach up to 48MHz, and it integrates 64KB Flash program memory and 8KB BSRAM data memory, meeting the storage and execution requirements of complex control algorithms. Its rich peripheral interfaces include communication interfaces such as UART, SPI, and I²C, as well as multiple ADC and PWM output channels, enabling flexible connection to external devices such as sensors and actuators to achieve real-time monitoring and precise control of the system status.

[0044] The power supply circuit converts the externally input DC28V voltage into a voltage suitable for the microcontroller and various driver circuits, providing stable power support for the entire controller. Specifically, for example... Figure 9 As shown, the DC28V voltage first undergoes overvoltage protection through the SMDJ36CA transient suppression diode D2. This diode is connected in parallel between the power supply input terminal and ground. When a transient high voltage spike occurs in the input voltage, D2 will quickly conduct, clamping the voltage within a safe range and preventing high voltage from damaging subsequent circuit components.

[0045] The DC28V voltage, after overvoltage protection, serves as the VOLTAGE power supply for the power supply circuit, providing power to modules in the controller that require high-voltage drive and acting as a reference input for voltage monitoring. It then enters a buck converter circuit composed of the MC34063 chip. The MC34063 acts as a buck controller; its input is connected to the VOLTAGE power supply via a filter circuit consisting of a parallel electrolytic capacitor and a ceramic capacitor to filter out noise interference from the input voltage. The MC34063's Switch Emitter pin (output of the switching transistor) is connected to inductor L1. This inductor, along with the electrolytic capacitor C4 and ceramic capacitor C20 at the output, forms an LC filter network. This network, in conjunction with the internal switching transistor's on / off action, converts the DC28V voltage into a stable 5V DC voltage, which is the VCC power supply. The MC34063's feedback pin (V-FB) monitors the output voltage in real time through a voltage divider resistor network. When the output voltage deviates from 5V, the chip's internal error amplifier adjusts the switching transistor's on-time to maintain a stable output voltage. The VCC power supply terminal supplies power to the driver chip in the control output circuit, the 74HC164 chip in the digital tube display driver circuit, the voltage divider circuit in the sensor acquisition circuit, and the microcontroller.

[0046] In addition, the voltage acquisition circuit is used to acquire the output voltage of the power supply circuit and transmit the acquired voltage signal to the microcontroller for easy monitoring of the power supply status. Specifically, the voltage acquisition circuit uses at least three shorting points, such as... Figure 10 As shown, these correspond to the DC28V input, VOLTAGE power supply terminal, and VCC power supply terminal, respectively. Each detection point is connected to the microcontroller's ADC interface through a voltage divider circuit.

[0047] When the circuit is operating, the shorting point is used to select the voltage node to be monitored via a soldered jumper. For example, when monitoring a DC28V input voltage, the jumper is connected to the DC28V node and the input of the voltage divider circuit; the voltage is then input to the microcontroller's P0.5 port after voltage division. When monitoring the VOLTAGE power supply, the jumper is connected to the VOLTAGE node, and the detection signal is also input to the P0.5 port. When monitoring the VCC power supply, the jumper is connected to the VCC node, and the signal is input to the same interface after voltage division. The microcontroller performs analog-to-digital conversion on the input signal using the ADC module and calculates the actual voltage value based on the voltage division ratio.

[0048] When a voltage ≤20V is detected and the duration exceeds 3 seconds, it is determined to be an undervoltage fault, triggering the display of fault code "E1";

[0049] When a voltage ≥32V is detected and the duration exceeds 3 seconds, it is determined to be an overvoltage fault, triggering the display of fault code "E2";

[0050] When the voltage at the VCC power supply terminal deviates from the range of 5V±0.5V for more than 3 seconds, it is determined to be a fault in the voltage regulator circuit, triggering the display of the E3 fault code.

[0051] like Figure 11 As shown, the low-voltage detection circuit includes an 817C optocoupler U5. Its input terminal has an LED connected in series with a voltage divider resistor R10 and a diode D5. One end of the voltage divider resistor R10 is connected to the VOLTAGE power supply terminal of the power supply circuit, and the other end is connected to the anode of the LED in the optocoupler. The cathode of the LED is connected to the PRESS_IN detection port through the diode D5. The collector of the output transistor is connected to the VCC power supply terminal of the power supply circuit, and the emitter is grounded through a pull-down resistor and the detection signal terminal is led out and connected to the I / O port P2.6 of the microcontroller.

[0052] When the system starts up and enters voltage monitoring mode, the PRESS_IN detection port is grounded through an external circuit, triggering the low-voltage detection logic. At this time, the VOLTAGE power supply terminal of the power supply circuit is applied to the anode of the LED at the input of the optocoupler through the voltage divider resistor R10, forming a detection loop. If the voltage at the VOLTAGE power supply terminal is lower than the system threshold, the current flowing through the LED is insufficient, causing the LED to fail to emit light, and the transistor at the output of the optocoupler U5 is cut off due to lack of light. At this time, the emitter is grounded through a pull-down resistor, and the detection signal terminal outputs a low level. After this low-level signal is transmitted to the microcontroller's P2.6 port, the microcontroller recognizes it as a low-voltage state and immediately triggers the protection mechanism.

[0053] like Figure 12 As shown, the buzzer driver circuit includes a second transistor Q9 and a speaker LS1. The base of the second transistor Q9 is connected to the SPEAKER_CTRL control terminal of the microcontroller through a current-limiting resistor R25. The emitter is grounded, and the collector is connected to the negative terminal of the speaker LS1. The positive terminal of the speaker LS1 is connected to the VCC power supply terminal of the power supply circuit to realize the output function of the prompt tone.

[0054] In summary, the automotive air conditioning controller of this application uses an automotive-grade KF8A100ETN microcontroller as its core, combined with a sensor acquisition circuit and a digital tube display driven by a 74HC164, to achieve high-precision temperature control and operating status display. It also integrates fault detection and alerts for voltage acquisition circuits, low-voltage detection circuits, and buzzer drive circuits, enabling accurate detection and intuitive alarms for power supply chain faults. Employing BTS724G / BTS4141N power switches and an MC34063 step-down circuit, it adapts to DC28V high-voltage input and stably outputs multiple voltage levels, meeting the power supply requirements of different modules and improving compatibility with diverse vehicle loads. Through optimized layout and integrated design, each circuit module enhances anti-interference capabilities while ensuring high performance, solving the problems of low integration and insufficient control output accuracy in traditional discrete component circuits, thus comprehensively improving the stability, reliability, and user experience of the automotive air conditioning system.

[0055] The above description is a further detailed explanation of the present utility model in conjunction with specific embodiments, and it should not be considered that the specific implementation of the present utility model is limited to this. For those skilled in the art to which the present utility model pertains and related fields, any extensions, operation methods, and data substitutions made based on the technical solution concept of the present utility model should fall within the protection scope of the present utility model.

Claims

1. A vehicle air conditioning controller, characterized in that, include: The button control circuit is used to receive the user's button commands and transmit the commands to the microcontroller; The control output circuit is used to control the working status of the compressor clutch, evaporator fan and heating actuator according to the instructions of the microcontroller; The sensor acquisition circuit is connected to the return air vent temperature sensor and the defrost temperature sensor respectively, and is connected to the microcontroller. It is used to acquire the vehicle interior temperature signal and the defrost temperature signal and transmit them to the microcontroller. The digital tube display driver circuit is connected to the microcontroller and is used to drive the digital tube to display the set temperature, the interior temperature, the defrost temperature and the fault code. The LED light driving circuit is connected to the microcontroller and is used to drive the air volume indicator, compressor working indicator and heating working indicator to turn on or off or flash. The microcontroller is used to receive and process signals transmitted by various circuits and output control commands. The power supply circuit is used to convert the externally input DC28V voltage into a voltage suitable for the microcontroller and driving various circuits.

2. The vehicle air conditioning controller according to claim 1, characterized in that, The control output circuit includes at least one BTS724G high-side power switch and at least one BTS4141N high-side power switch. The input terminal of the BTS724G is connected to the I / O port of the microcontroller, and the output terminal is connected to the control terminal of the compressor clutch and the evaporator fan. The input terminal of the BTS4141N is connected to the I / O port of the microcontroller, and the output terminal is connected to the control terminal of the heating actuator.

3. The vehicle air conditioning controller according to claim 2, characterized in that, The sensor acquisition circuit includes a first voltage divider circuit and a second voltage divider circuit. The first voltage divider circuit is composed of the return air vent temperature sensor and a first fixed resistor connected in series. The second voltage divider circuit is composed of the defrost temperature sensor and a second fixed resistor connected in series. The output terminals of the first voltage divider circuit and the second voltage divider circuit are respectively connected to the I / O port of the microcontroller.

4. The vehicle air conditioning controller according to claim 3, characterized in that, The digital tube display driver circuit includes a 74HC164 serial input parallel output shift register. The CLK and DATA terminals of the 74HC164 are respectively connected to the I / O ports of the microcontroller. The output terminal is connected to the segment selection terminal of the two common cathode digital tube through a current limiting resistor. The digit selection terminal of the digital tube is connected to the I / O port of the microcontroller through a transistor driver circuit.

5. A vehicle air conditioning controller according to claim 2, characterized in that, The LED driving circuit includes a first transistor. The base of the first transistor is connected to the I / O port of the microcontroller through a first resistor. The emitter of the first transistor is grounded. The collector of the first transistor is connected to the power supply control terminals of the fan speed indicator, the compressor working indicator, and the heating working indicator through a second resistor.

6. The vehicle air conditioning controller according to claim 1, characterized in that, The microcontroller uses the KF8A100ETN chip.

7. The vehicle air conditioning controller according to claim 1, characterized in that, The buttons include a fan speed adjustment button, an A / C control button, a temperature setting up button, a temperature setting down button, and a heating button.

8. The vehicle air conditioning controller according to claim 1, characterized in that, The vehicle air conditioning controller also includes a voltage acquisition circuit, which is used to acquire the output voltage of the power supply circuit and transmit the acquired voltage signal to the microcontroller.

9. A vehicle air conditioning controller according to claim 1, characterized in that, The vehicle air conditioning controller also includes a low-voltage detection circuit, which includes an optocoupler. The input terminal of the optocoupler has a light-emitting diode connected in series with a voltage divider resistor and a diode. One end of the voltage divider resistor is connected to the VOLTAGE power supply terminal of the power supply circuit, and the other end is connected to the anode of the light-emitting diode of the optocoupler. The cathode of the light-emitting diode of the optocoupler is connected to the PRESS_IN detection port through the diode. The collector of the transistor at the output terminal of the optocoupler is connected to the VCC power supply terminal of the power supply circuit, and the emitter is grounded through a pull-down resistor. The detection signal terminal of the emitter is connected to the I / O port of the microcontroller.

10. A vehicle air conditioning controller according to claim 1, characterized in that, The vehicle air conditioning controller also includes a buzzer driving circuit, which includes a second transistor and a speaker. The base of the second transistor is connected to the SPEAKER_CTRL control terminal of the microcontroller through a current-limiting resistor. The emitter of the second transistor is grounded, and the collector of the second transistor is connected to the negative terminal of the speaker. The positive terminal of the speaker is connected to the VCC power supply terminal of the power supply circuit.

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