A testing device for an air conditioner main board

Abstract

This invention aims to provide a testing device for an air conditioner motherboard. The invention includes an air conditioner motherboard connected to a testing device via a digital potentiometer board. The digital potentiometer board includes a first resistor. The air conditioner motherboard includes an MCU unit and a temperature sensor socket. The MCU unit is connected to the digital potentiometer board via a temperature sensing circuit, which includes a second resistor and a third resistor. The node between the temperature sensor socket and the third resistor is grounded via the second resistor and a first capacitor, respectively. The node between the third resistor and the MCU unit is grounded via the second capacitor. The temperature sensor socket is connected to a 5V voltage and is connected to the first resistor. This invention applies to the technical field of motherboard testing.

Description

Technical Field

[0001] This invention relates to the technical field of motherboard testing, and in particular to a testing device for an air conditioner motherboard. Background Technology

[0002] Air conditioning is an integral part of people's lives, providing a comfortable living environment by adjusting indoor temperature. This relies on various temperature sensors and their circuits within the air conditioner's mainboard, primarily including pipe temperature sensors and room temperature sensors. Because temperature sensing is a crucial component of the air conditioner's mainboard functionality, this circuitry requires extensive and comprehensive testing after the mainboard is manufactured. One existing method for testing the temperature sensing circuitry on air conditioner mainboards involves connecting a real temperature sensor. The mainboard's MCU's internal ADC reads the voltage returned by the sensor and further analyzes it to determine the temperature value. This approach relies on manual plugging and unplugging, which is inefficient, especially for applications requiring aging tests, and may also cause significant wear and tear on the temperature sensor.

[0003] In addition, the air conditioner mainboard also has functions such as electric auxiliary heating and four-way valve control. It typically uses 220VAC AC power and employs a high-voltage switch for on / off control. The high-voltage switch varies depending on the brand and model, but it usually uses a relay-like switching device capable of withstanding high voltage. However, existing air conditioner mainboard testing methods only measure the continuity of the high-voltage switch; simply reading the voltage is sufficient, or, based on empirical data and yield considerations, this measurement may be selectively ignored. While the aforementioned method generally indicates no major functional problems when the high-voltage switch is detected after conduction, it suffers from insufficient load-carrying capacity. Therefore, it is necessary to provide a testing device for the air conditioner mainboard. This device uses probe contact and, based on the structural characteristics of the temperature sensing circuit of the mainboard, employs a digital potentiometer to control different voltage division ratios, enabling the mainboard to quickly obtain different temperature sampling data, improving testing efficiency. A multimeter can be used to obtain the continuity status of up to eight high-voltage switches on the mainboard and acquire the current in these circuits to further determine the load-carrying capacity of the currently used high-voltage switches, thereby improving the testing yield of the air conditioner mainboard. Summary of the Invention

[0004] The technical problem to be solved by this invention is to overcome the shortcomings of the prior art and provide a testing device for air conditioner mainboards. By using a probe contact method and based on the structural characteristics of the temperature sensing circuit of the air conditioner mainboard, a digital potentiometer is selected to control different voltage division ratios of the circuit, so that the air conditioner mainboard can quickly obtain different temperature sampling data, thereby improving testing efficiency. By using a multimeter to obtain the conduction status of up to 8 high-voltage switches of the air conditioner mainboard and to obtain the current of these circuits, the load-carrying capacity of the currently used high-voltage switches can be further determined, thereby improving the test yield of the air conditioner mainboard.

[0005] The technical solution adopted in this invention is as follows: This invention includes an air conditioner mainboard, which is connected to a test device via a digital potentiometer board. The digital potentiometer board includes a first resistor. The air conditioner mainboard includes an MCU unit and a temperature sensor socket. The MCU unit is connected to the digital potentiometer board via a temperature sensing circuit. The temperature sensing circuit includes a second resistor and a third resistor. The node between the temperature sensor socket and the third resistor is grounded via the second resistor and the first capacitor, respectively. The node between the third resistor and the MCU unit is grounded via the second capacitor. The temperature sensor socket is connected to a 5V voltage. The temperature sensor socket is connected to the first resistor. The third resistor and the second capacitor form a first-stage low-pass filter. A voltage divider circuit is created through the 5V power supply and the second resistor to simulate a real temperature sensor, providing a voltage divider value to the MCU unit, thereby enabling the determination of the corresponding temperature value. As can be seen from the above scheme, this application, through probe contact and based on the structural characteristics of the temperature sensing circuit of the air conditioner mainboard, selects a digital potentiometer to control different voltage division ratios of the circuit, enabling the air conditioner mainboard to quickly obtain different temperature sampling data, thus significantly improving testing efficiency. This application, as a functional testing method for the temperature detection circuit of the air conditioner mainboard, has a significant efficiency advantage compared to manual operation.

[0006] In a preferred embodiment, the temperature sensor socket is connected to the interface of the digital potentiometer board via a probe, with the 5V signal of the temperature sensor socket and the temperature sensing circuit connected to the B1 pin of the digital potentiometer board. The temperature sensing circuit is connected to the W1 pin of the digital potentiometer board. The first resistor and the second resistor form a voltage divider, and the specific voltage divider formula is: Temp_DIV1 = 5V*(R1 / (R1+ Rset1)).

[0007] In a preferred embodiment, the digital potentiometer board is a dual-channel digital potentiometer. The dual-channel digital potentiometer interacts with the test equipment via an I2C bus. By receiving instructions from the test equipment, the dual-channel digital potentiometer is controlled to set different resistance values, thereby obtaining different voltage division values ​​of the temperature sensing circuit.

[0008] In a preferred embodiment, the MCU unit is connected to the temperature sensing circuit via a temperature acquisition circuit, and the sampling interface corresponding to the temperature acquisition circuit is ADC1.

[0009] In a preferred embodiment, the air conditioner mainboard further includes a high-voltage switch and a load socket. The 220VAC live wire AC_L is connected to the high-voltage switch, and the other end of the high-voltage switch is the AC_L_OUT terminal. The AC_L_OUT terminal is connected to the load socket, and the load socket is connected to an AC load switching board via a cable. The AC load switching board includes an input switch, a Hall current sensor, and an AC load. The input switch is connected to the input port IN+ of the Hall current sensor, and the output port IN- of the Hall current sensor is connected to the AC load. A multimeter is connected to the voltage output terminal of the Hall current sensor. Attached Figure Description

[0010] Figure 1 This is a system block diagram of the present invention; Figure 2 This is the circuit schematic of the digital potentiometer board; Figure 3 This is a circuit diagram of the inlet switch and the Hall current sensor. Detailed Implementation

[0011] like Figures 1 to 2 As shown, in this embodiment, the present invention includes an air conditioner mainboard 1, which is connected to a test device 3 via a digital potentiometer board 2. The digital potentiometer board 2 includes a first resistor Rset1. The air conditioner mainboard 1 includes an MCU unit 4 and a temperature sensor socket J1. The MCU unit 4 is connected to the digital potentiometer board 2 via a temperature sensing circuit Temp_DIV1. The temperature sensing circuit Temp_DIV1 includes a second resistor R1 and a third resistor R2. The node of the temperature sensor socket J1 and the third resistor R2 is grounded via the second resistor R1 and the first capacitor C1, respectively. The node of the third resistor R2 and the MCU unit 4 is grounded via the second capacitor C2. The temperature sensor socket J1 is connected to a 5V voltage and is connected to the first resistor Rset1. The third resistor R2 and the second capacitor C2 form a first-stage low-pass filter. Through the 5V power supply and the second resistor R1, a voltage divider circuit is created to simulate a real temperature sensor, providing a voltage divider value to the MCU unit 4, thereby enabling the corresponding temperature value to be determined.

[0012] The air conditioner mainboard 1 has two temperature sensing circuits, Temp_DIV1. The temperature sensor socket J1 has two pins, a power supply voltage of 5V, and the Temp_DIV1 temperature sensing circuit. The second resistor R1 is a pull-down resistor, the first capacitor C1 is a filter capacitor, and the third resistor R2 is a current-limiting resistor, which, together with the second capacitor C2, forms a first-stage low-pass filter. Based on this, using the 5V power supply and the second resistor R1, an external voltage divider circuit is created. This simulates a real temperature sensor, providing a voltage divider value to the MCU unit 4, thereby enabling the determination of a corresponding temperature value.

[0013] like Figures 1 to 2 As shown, in this embodiment, the temperature sensor socket J1 connects the 5V signal of the temperature sensor socket J1 and the temperature sensing circuit Temp_DIV1 to the interface of the digital potentiometer board 2 via probe 6. The 5V signal is connected to pin B1 of the digital potentiometer board 2, and the temperature sensing circuit Temp_DIV1 is connected to pin W1 of the digital potentiometer board 2. The first resistor Rset1 and the second resistor R1 form a voltage divider. The specific voltage divider formula is: Temp_DIV1 = 5V * (R1 / (R1 + Rset1)).

[0014] like Figures 1 to 2 As shown, in this embodiment, the digital potentiometer board 2 is a dual-channel digital potentiometer. This dual-channel digital potentiometer interacts with the test device 3 via an I2C bus. By receiving instructions from the test device 3, it controls the dual-channel digital potentiometer to set different resistance values, thereby obtaining different voltage division values ​​for the temperature sensing circuit Temp_DIV1. The first resistor Rset1 is a variable resistor. The model of the digital potentiometer board 2 is AD5248BRMZ10, which provides a variable resistor with a 10K ohm range. The dual-channel digital potentiometer interacts with the test device 3 via an I2C bus. By receiving instructions from the test device 3, it can control the digital potentiometer to set different resistance values, thereby obtaining different voltage division values ​​for Temp_DIV1.

[0015] like Figures 1 to 2 As shown, in this embodiment, the MCU unit 4 is connected to the temperature sensing circuit Temp_DIV1 via the temperature acquisition circuit Temp_IN1, and the sampling interface corresponding to the temperature acquisition circuit Temp_IN1 is ADC1. The ADC interface corresponding to the MCU unit 4 can obtain different voltage division values ​​to simulate the temperature change process, thereby realizing the detection of the circuit.

[0016] like Figure 1 and Figure 3As shown, in this embodiment, the air conditioner mainboard 1 also includes a high-voltage switch S1 and a load socket 7. The 220VAC of the live wire AC_L is connected to the high-voltage switch S1. The other end of the high-voltage switch S1 is the AC_L_OUT terminal, which is connected to the load socket 7. The load socket 7 is connected to an AC load switching board 9 via a cable 8. The AC load switching board 9 includes an input switch S2, a Hall current sensor 10, and an AC load 11. The input switch S2 is connected to the input port IN+ of the Hall current sensor 10, and the output port IN- of the Hall current sensor 10 is connected to the AC load 11. A multimeter 12 is connected to the voltage output terminal of the Hall current sensor 10.

[0017] The high-voltage switch S1 is one of the eight inlet switches. The high-voltage switch S1 connects to the input port IN+ of the Hall current sensor 10, and then to the AC load 11 via the output port IN-. The AC load 11 can be a 100W light bulb or a 200W / 50Ohm aluminum-cased cement resistor, or other AC loads that meet the specifications. The voltage output terminal of the Hall current sensor is connected to a multimeter to read the voltage. The Hall current sensor 10 is model TMCS1100A2QDR, and its voltage-to-current ratio is 100 mV / A. That is, when the multimeter 12 measures 100mV, it means that the current flowing through the circuit is 1A. By using the multimeter 12 to obtain the conduction status of up to eight high-voltage switches on the air conditioning mainboard and to obtain the current in these circuits, the load-carrying capacity of the currently used high-voltage switches can be further determined.

[0018] Although the embodiments of the present invention are described with reference to actual solutions, they do not constitute a limitation on the meaning of the present invention. Modifications to the embodiments and combinations with other solutions based on this specification will be obvious to those skilled in the art.

Claims

1. A testing device for an air conditioner main board, comprising an air conditioner main board (1), characterized in that: The air conditioner mainboard (1) is connected to the test equipment (3) via a digital potentiometer board (2). The digital potentiometer board (2) includes a first resistor (Rset1). The air conditioner mainboard (1) includes an MCU unit (4) and a temperature sensor socket (J1). The MCU unit (4) is connected to the digital potentiometer board (2) via a temperature sensing circuit (Temp_DIV1). The temperature sensing circuit (Temp_DIV1) includes a second resistor (R1) and a third resistor (R2). The nodes of the temperature sensor socket (J1) and the third resistor (R2) are respectively connected via the second... The resistor (R1) and the first capacitor (C1) are grounded. The third resistor (R2) and the node of the MCU unit (4) are grounded through the second capacitor (C2). The temperature sensor socket (J1) is connected to a 5V voltage. The temperature sensor socket (J1) is connected to the first resistor (Rset1). The third resistor (R2) and the second capacitor (C2) form a first-stage low-pass filter. A voltage divider circuit is created through the 5V power supply and the second resistor (R1) to simulate a real temperature sensor and provide a voltage divider value to the MCU unit (4), thereby enabling the corresponding temperature value to be resolved.

2. The test device of claim 1, wherein, The temperature sensor socket (J1) is connected to the interface of the digital potentiometer board (2) via the probe (6) with the 5V signal of the temperature sensor socket (J1) and the temperature sensing circuit (Temp_DIV1). The 5V signal is connected to the B1 pin of the digital potentiometer board (2), and the temperature sensing circuit (Temp_DIV1) is connected to the W1 pin of the digital potentiometer board (2). The first resistor (Rset1) and the second resistor (R1) form a voltage divider. The specific voltage divider formula is: Temp_DIV1 = 5V*(R1 / (R1+ Rset1)).

3. The test device of claim 1, wherein, The digital potentiometer board (2) is a dual-channel digital potentiometer. The dual-channel digital potentiometer interacts with the test device (3) via the I2C bus. By receiving instructions from the test device (3), the dual-channel digital potentiometer is controlled to set different resistance values, thereby obtaining different voltage division values ​​of the temperature sensing circuit (Temp_DIV1).

4. The testing device for the air conditioner mainboard according to claim 1, characterized in that, The MCU unit (4) is connected to the temperature sensing circuit (Temp_DIV1) via the temperature acquisition circuit (Temp_IN1), and the sampling interface corresponding to the temperature acquisition circuit (Temp_IN1) is ADC1.

5. The testing device for the air conditioner mainboard according to claim 1, characterized in that, The air conditioner mainboard (1) also includes a high-voltage switch (S1) and a load socket (7). The 220VAC of the live wire AC_L is connected to the high-voltage switch (S1). The signal at the other end of the high-voltage switch (S1) is the AC_L_OUT terminal. The AC_L_OUT terminal is connected to the load socket (7). The load socket (7) is connected to an AC load switching board (9) via a cable (8). The AC load switching board (9) includes an inlet switch (S2), a Hall current sensor (10), and an AC load (11). The inlet switch (S2) is connected to the input port IN+ of the Hall current sensor (10). The output port IN- of the Hall current sensor (10) is connected to the AC load (11). The voltage output terminal of the Hall current sensor (10) is connected to a multimeter (12).

Images