Array type semiconductor chilling plate temperature control device and control method thereof

Abstract

The invention relates to an array type semiconductor chilling plate temperature control device. The device comprises a power supply module; a voltage output module; an infrared thermal imaging module; the MCU main control module is used for controlling multi-path voltage output of the voltage output module, receiving multi-path current signals acquired by the voltage output module, receiving temperature signals acquired by the infrared thermal imaging module, performing double-ring PID calculation and communicating with an upper computer; a refrigeration sheet array; and an upper computer. The invention further discloses a control method of the array type semiconductor chilling plate temperature control device. According to the invention, a PWM control mode is replaced by an output voltage mode that the DAC outputs analog voltage to control the voltage output module; the cost of the design scheme is lower than the design cost of a high-frequency PWM circuit; according to the invention, the temperature control of different refrigeration sheets can be realized by outputting multiple paths of voltage to control the refrigeration sheets and monitoring the temperature of different refrigeration sheets by the infrared thermal imaging module, so that different temperature field outputs are formed.

Description

Technical Field

[0001] This invention relates to the field of thermoelectric cooling array technology, and in particular to a thermoelectric cooling array temperature control device and its control method. Background Technology

[0002] Traditional thermoelectric cooler (TCU) driving schemes primarily employ PWM (Pulse Width Modulation) to regulate the output voltage duty cycle. This can be categorized into two methods: PWM duty cycle regulation under fixed voltage and constant current. Under the fixed voltage and fixed current PWM regulation method, when the PWM signal is high, the TCU cools normally, causing the cold side temperature to decrease and the hot side temperature to increase. When the PWM signal is low, the TCU stops cooling, and due to the temperature difference, the cold side temperature is affected by both ambient and hot side temperatures, causing it to rise again.

[0003] The PWM operating mode reveals that the thermoelectric cooler is constantly in a cycle of operation, resulting in significant periodic temperature fluctuations. Specifically, for the cold side, when the temperature difference from the ambient temperature is small, the PWM duty cycle is large, meaning the cooler is inactive for longer periods than it is active. This leads to a larger upward fluctuation in the cold side temperature compared to the set constant temperature. Conversely, when the temperature difference from the ambient temperature is large, the PWM duty cycle is small, resulting in a larger downward fluctuation in the cold side temperature compared to the set constant temperature. To reduce this fluctuation, the PWM switching frequency needs to be increased; a higher PWM switching frequency results in a smaller temperature fluctuation. However, higher PWM frequencies significantly increase the circuit design cost and complexity. Furthermore, the PWM operating mode easily leads to localized thermal stress in the thermoelectric cooler. Frequent current switching causes the semiconductor chips inside the cooler to repeatedly experience thermal expansion and contraction. This thermal cycle generates mechanical stress, which, over time, reduces the reliability and lifespan of the cooler, and may even lead to internal solder joint failure or chip breakage, rendering the cooler malfunction.

[0004] In terms of temperature output, many thermoelectric cooler array devices only allow multiple thermoelectric coolers to input the same driving voltage, which means that different temperature control cannot be output for each thermoelectric cooler in the array. Only a single temperature field can be formed, which is not conducive to use in some scenarios that require different temperature control. Summary of the Invention

[0005] To address the issues of reduced lifespan of PWM-controlled thermoelectric coolers due to repeated thermal expansion and contraction of the cooler chips under low frequency and high duty cycle current switching, and the high design cost of high-frequency PWM circuits, the primary objective of this invention is to provide an array-type thermoelectric cooler temperature control device that uses a DAC output analog voltage control module to replace PWM control, resulting in lower design costs and the ability to control the temperature of different thermoelectric coolers, thereby creating different temperature field outputs.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: an array-type semiconductor refrigeration chip temperature control device, comprising:

[0007] The power module provides the initial input voltage to power the voltage output module, the MCU main control module, and the thermoelectric array.

[0008] The voltage output module is used to convert the initial input voltage to multiple 400mV to 6.6V voltages and output them to the thermoelectric array;

[0009] Infrared thermal imaging module is used to acquire temperature signals of the cooling chips or objects on the cooling chips at different positions of the cooling chip array;

[0010] The MCU main control module is used to control the multi-channel voltage output of the voltage output module, receive the multi-channel current signals collected by the voltage output module, receive the temperature signals collected by the infrared thermal imaging module, perform dual-loop PID calculations, and communicate with the host computer.

[0011] A cooling chip array is used to receive multiple adjustable voltages from a voltage output module to achieve temperature control of the cooling chip or the object supported on the cooling chip in different areas.

[0012] The host computer is used to communicate with the MCU main control module and set the temperature of different areas of the thermoelectric array.

[0013] The power supply module uses a switching power supply, model YX5603; the MCU main control module uses an STM32F104ZET6 controller; the infrared thermal imaging module is model MLX90642BAC; and the thermoelectric cooler array is model HT064304, using a 6×6 array.

[0014] The voltage output module includes a DAC circuit, a multi-channel adjustable step-down circuit, and a current sampling circuit. The DAC circuit is connected to the multi-channel adjustable step-down circuit, which is connected to the current sampling circuit. The DAC circuit and the current sampling circuit are connected to the MCU main control module. The multi-channel adjustable step-down circuit needs to be connected to the power supply module and the thermoelectric cooler array.

[0015] The DAC circuit includes a DAC chip U2, capacitors C8 and C9. The DAC chip U2 is a BH2221FV chip. The power supply terminal VCC of the BH2221FV chip is connected to the 3V3 power supply provided by the MCU main control module through capacitor C8. The analog power input terminal VDD of the BH2221FV chip is also connected to the 3V3 power supply provided by the MCU main control module through capacitor C9. The DAC chip provides multiple analog voltage output terminals, namely VO1 to VO12, which are connected to the multi-channel adjustable step-down circuit of the voltage output module for outputting multiple voltages. The communication port of the DAC chip U2 is connected to the second communication port of the MCU control module for communication with the MCU control module, thereby controlling the output voltage value of the DAC circuit.

[0016] The multi-channel adjustable buck circuit consists of multiple adjustable buck circuits with identical structures. Each adjustable buck circuit includes a DC-DC power chip U1, capacitors C1, C2, C3, C4, C5, C6, and C7, resistors R1, R2, and R3, diodes D1 and D2, inductor L1, and current sampling resistor R4. The DC-DC power chip U1 uses a YX5603 chip. The initial input voltage of the power module is connected to the power input pin VIN of the DC-DC power chip U1 through parallel capacitors C1, C2, and C3. The output pin SW of the DC-DC power chip U1 is connected in series with inductor L1 and then in parallel with capacitors C4, C5, and C6 as the positive terminal of the voltage output. One end of the current sampling resistor R4 is grounded, and the current sampling resistor R... The other end of 4 serves as the negative terminal of the voltage output terminal; the enable terminal EN of the DC-DC power chip U1 is connected to the multi-channel enable output terminal of the MCU control module; the feedback pin FB of the DC-DC power chip U1 is connected to resistors R1, R2, and R3 respectively; the other end of resistor R1 is connected to one end of inductor L1 and capacitor C6 respectively; capacitors C6, C5, and C4 are connected in parallel and share a common ground; the other end of inductor L1 is connected to the SW pin of the DC-DC power chip U1, capacitor C7, and the cathode of diode D1 respectively; the anode of diode D1 is grounded; the other end of capacitor C7 is connected to the BST pin of the DC-DC power chip U1; resistor R3 is connected to the cathode of diode D2; and the anode of diode D2 is connected to the output voltage VO1 of the DAC circuit.

[0017] The cooling chip array includes an alumina ceramic plate, multiple semiconductor cooling chips, a cooling fan, a connecting circuit board, and a support mold. The multiple semiconductor cooling chips are attached to the alumina ceramic plate with silicone grease to form an array. The two wires of the semiconductor cooling chips are connected to the connecting circuit board through holes in the alumina ceramic plate. The support mold is used to assemble the connecting circuit board, the cooling fan, and the alumina ceramic plate.

[0018] The adjustable step-down circuit's output voltage range is achieved by controlling the values ​​of resistors R1, R2, and R3, which affect the output voltage of the DAC circuit. When it is 0, to ensure the maximum output value It must satisfy the following formula:

[0019] ;

[0020] in, The reference voltage value for the feedback pin of the DC-DC power supply chip U1; When the maximum value is 3.3V, to ensure the minimum output value is The following formula must be satisfied:

[0021] .

[0022] The current sampling circuit includes an analog switch U3, a current sensing amplifier U4, capacitors C10 and C11. The analog switch U3 uses a 74HC4067PW chip, and the current sensing amplifier U4 uses an INA226 chip. The power input pin VCC of the analog switch U3 is connected to the 3V3 power supply provided by the MCU control module through capacitor C10, and the power input pin VCC of the current sensing amplifier U4 is connected to the 3V3 power supply provided by the MCU control module through capacitor C11.

[0023] The multiple switch input pins Y1 to Y9 of the analog switch U3 are respectively connected to the negative terminal of the voltage output of each channel in the multi-channel adjustable step-down circuit of the voltage output module. The switch output pin Z is connected to the input pin VIN+ of the current sensing amplifier U4. The strobe signal pins S0 to S3 are connected to the analog switch control output terminal of the MCU control module. The communication ports SDA and SCL of the current sensing amplifier U4 are connected to the third communication port of the MCU control module for communication with the MCU control module, thereby transmitting the acquired current signal.

[0024] Another object of the present invention is to provide a control method for an array-type semiconductor refrigeration chip temperature control device, the method comprising the following sequential steps:

[0025] (1) Set the target area and target temperature to be controlled on the host computer and transmit them to the MCU main control module;

[0026] (2) The infrared thermal imaging module collects the temperature of the cooling chip or the item on the chip in the target area and transmits it to the MCU main control module;

[0027] (3) The MCU main control module adopts a dual-loop PID algorithm to calculate the outer loop temperature loop and obtain the target output current. ;

[0028] (4) The MCU main control module collects the current flowing through the cooling chip in the target area;

[0029] (5) The MCU main control module calculates the steady-state feedforward current. A dual-loop PID algorithm is used to calculate the inner current loop and obtain the output voltage required by the DAC circuit. And control the DAC circuit output of the voltage output module. ;

[0030] (6) Each time time elapses Repeat steps (2) to (5).

[0031] In step (3), the target output current The calculation formula is:

[0032] ;

[0033] in, This indicates the current time of PID calculation. This indicates the time of the previous PID calculation. This is the temperature loop proportionality coefficient. The temperature error calculated at the current moment. This represents the temperature error from the previous moment. The integral coefficient of the temperature loop is... The integral coefficient of the temperature loop is... Sampling period; temperature error The calculation formula is as follows:

[0034] ;

[0035] in, The temperature collected at the current PID calculation moment. The desired temperature is set for the host computer.

[0036] In step (5), the steady-state feedforward current The calculation formula is as follows:

[0037] ;

[0038] in, The Seebeck coefficient is... The resistance of the thermoelectric cooler. For the thermal conductivity of the cooling chip, The temperature of the hot surface of the cooling element; The desired temperature is set for the host computer.

[0039] Calculate the inner current loop:

[0040] ;

[0041] in, This is the proportionality coefficient of the current loop. The current error at the current moment. This represents the current error at the previous moment. The integral coefficient of the current loop is... These are the differential coefficients of the current loop. The sampling period is This is the output voltage required by the DAC circuit;

[0042] Current error at current moment The calculation formula is as follows:

[0043] ;

[0044] in, This represents the actual current collected at the current moment.

[0045] As can be seen from the above technical solution, the beneficial effects of the present invention are as follows: First, by using the DAC output analog voltage control voltage output module to replace the PWM control method, the problem of reduced lifespan of the cooling chip caused by repeated thermal expansion and contraction of the chip under frequent current switching is prevented; Second, the design cost of the present invention is lower than that of high-frequency PWM circuit design; Third, the present invention can achieve temperature control of different cooling chips by controlling the cooling chips with multiple output voltages and monitoring the temperature of different cooling chips with an infrared thermal imaging module, thereby forming different temperature field outputs. Attached Figure Description

[0046] Figure 1 This is a block diagram of the device structure of the present invention;

[0047] Figure 2 This is the circuit schematic of the DAC circuit and the adjustable buck circuit in the voltage output module;

[0048] Figure 3 This is the circuit schematic of the current sampling circuit in the voltage output module. Detailed Implementation

[0049] like Figure 1 As shown, an array-type semiconductor refrigeration temperature control device includes:

[0050] The power module provides the initial input voltage to power the voltage output module, the MCU main control module, and the thermoelectric array.

[0051] The voltage output module is used to convert the initial input voltage to multiple 400mV to 6.6V voltages and output them to the thermoelectric array;

[0052] Infrared thermal imaging module is used to acquire temperature signals of the cooling chips or objects on the cooling chips at different positions of the cooling chip array;

[0053] The MCU main control module is used to control the multi-channel voltage output of the voltage output module, receive the multi-channel current signals collected by the voltage output module, receive the temperature signals collected by the infrared thermal imaging module, perform dual-loop PID calculations, and communicate with the host computer.

[0054] A cooling chip array is used to receive multiple adjustable voltages from a voltage output module to achieve temperature control of the cooling chip or the object supported on the cooling chip in different areas.

[0055] The host computer is used to communicate with the MCU main control module and set the temperature of different areas of the thermoelectric array.

[0056] The power supply module uses a switching power supply, model YX5603; the MCU main control module uses an STM32F104ZET6 controller; the infrared thermal imaging module is model MLX90642BAC; and the thermoelectric cooler array is model HT064304, using a 6×6 array.

[0057] The voltage output module includes a DAC circuit, a multi-channel adjustable step-down circuit, and a current sampling circuit. The DAC circuit is connected to the multi-channel adjustable step-down circuit, which is connected to the current sampling circuit. The DAC circuit and the current sampling circuit are connected to the MCU main control module. The multi-channel adjustable step-down circuit needs to be connected to the power supply module and the thermoelectric cooler array.

[0058] like Figure 2 As shown, the DAC circuit includes a DAC chip U2, capacitor C8, and capacitor C9. The DAC chip U2 is a BH2221FV chip. The power supply terminal VCC of the BH2221FV chip is connected to the 3V3 power supply provided by the MCU main control module through capacitor C8, and the analog power input terminal VDD of the BH2221FV chip is connected to the 3V3 power supply provided by the MCU main control module through capacitor C9. The DAC chip provides multiple analog voltage output terminals, namely VO1 to VO12, which are connected to the multi-channel adjustable step-down circuit of the voltage output module for outputting multiple voltages. The communication port of the DAC chip U2 is connected to the second communication port of the MCU control module for communicating with the MCU control module, thereby controlling the output voltage value of the DAC circuit. Figure 2 In the diagram, 1 represents an adjustable step-down circuit, and 2 represents a DAC circuit.

[0059] like Figure 2As shown, the multi-channel adjustable buck circuit consists of multiple adjustable buck circuits with identical structures. Each adjustable buck circuit includes a DC-DC power chip U1, capacitors C1, C2, C3, C4, C5, C6, and C7, resistors R1, R2, and R3, diodes D1 and D2, inductor L1, and a current sampling resistor R4. The DC-DC power chip U1 uses a YX5603 chip. The initial input voltage of the power module is connected to the power input pin VIN of the DC-DC power chip U1 through parallel capacitors C1, C2, and C3. The output pin SW of the DC-DC power chip U1 is connected in series with inductor L1 and then in parallel with capacitors C4, C5, and C6 as the positive terminal of the voltage output. One end of the current sampling resistor R4 is grounded, and the current sampling resistor... The other end of resistor R4 serves as the negative terminal of the voltage output. The enable terminal EN of the DC-DC power chip U1 is connected to the multi-channel enable output terminal of the MCU control module. The feedback pin FB of the DC-DC power chip U1 is connected to resistors R1, R2, and R3 respectively. The other end of resistor R1 is connected to one end of inductor L1 and capacitor C6 respectively. Capacitors C6, C5, and C4 are connected in parallel and share a common ground. The other end of inductor L1 is connected to the SW pin of DC-DC power chip U1, capacitor C7, and the cathode of diode D1 respectively. The anode of diode D1 is grounded. The other end of capacitor C7 is connected to the BST pin of DC-DC power chip U1. Resistor R3 is connected to the cathode of diode D2. The anode of diode D2 is connected to the output voltage VO1 of the DAC circuit.

[0060] The cooling chip array includes an alumina ceramic plate, multiple semiconductor cooling chips, a cooling fan, a connecting circuit board, and a support mold. The multiple semiconductor cooling chips are attached to the alumina ceramic plate with silicone grease to form an array. The two wires of the semiconductor cooling chips are connected to the connecting circuit board through holes in the alumina ceramic plate. The support mold is used to assemble the connecting circuit board, the cooling fan, and the alumina ceramic plate.

[0061] The adjustable step-down circuit's output voltage range is achieved by controlling the values ​​of resistors R1, R2, and R3, which affect the output voltage of the DAC circuit. When it is 0, to ensure the maximum output value It must satisfy the following formula:

[0062] ;

[0063] in, The reference voltage value for the feedback pin of the DC-DC power supply chip U1; When the maximum value is 3.3V, to ensure the minimum output value is The following formula must be satisfied:

[0064] .

[0065] In this embodiment of the invention, resistors R1 and R2 are 160kΩ and 5kΩ, respectively. Meanwhile, the output voltage of the DAC circuit... To ensure a minimum output value of 400mV when the maximum value is 3.3V, the following formula must be satisfied:

[0066]

[0067]

[0068] ;

[0069] Substituting the values ​​of R1, R2, and R2 obtained above... From the given value, R3 is approximately 83kΩ, and the commonly used resistor value of 82kΩ is recommended.

[0070] like Figure 3 As shown, the current sampling circuit includes an analog switch U3, a current sensing amplifier U4, capacitor C10, and capacitor C11. The analog switch U3 uses a 74HC4067PW chip, and the current sensing amplifier U4 uses an INA226 chip. The power input pin VCC of the analog switch U3 is connected to the 3V3 power supply provided by the MCU control module through capacitor C10, and the power input pin VCC of the current sensing amplifier U4 is connected to the 3V3 power supply provided by the MCU control module through capacitor C11.

[0071] The multiple switch input pins Y1 to Y9 of the analog switch U3 are respectively connected to the negative terminal of the voltage output of each channel in the multi-channel adjustable step-down circuit of the voltage output module. The switch output pin Z is connected to the input pin VIN+ of the current sensing amplifier U4. The strobe signal pins S0 to S3 are connected to the analog switch control output terminal of the MCU control module. The communication ports SDA and SCL of the current sensing amplifier U4 are connected to the third communication port of the MCU control module for communication with the MCU control module, thereby transmitting the acquired current signal.

[0072] This method includes the following steps in sequence:

[0073] (1) Set the target area and target temperature to be controlled on the host computer and transmit them to the MCU main control module;

[0074] (2) The infrared thermal imaging module collects the temperature of the cooling chip or the item on the chip in the target area and transmits it to the MCU main control module;

[0075] (3) The MCU main control module adopts a dual-loop PID algorithm to calculate the outer loop temperature loop and obtain the target output current. ;

[0076] (4) The MCU main control module collects the current flowing through the cooling chip in the target area;

[0077] (5) The MCU main control module calculates the steady-state feedforward current. A dual-loop PID algorithm is used to calculate the inner current loop and obtain the output voltage required by the DAC circuit. And control the DAC circuit output of the voltage output module. ;

[0078] (6) Each time time elapses Repeat steps (2) to (5).

[0079] In step (3), the target output current The calculation formula is:

[0080] ;

[0081] in, This indicates the current time of PID calculation. This indicates the time of the previous PID calculation. This is the temperature loop proportionality coefficient. The temperature error calculated at the current moment. This represents the temperature error from the previous moment. The integral coefficient of the temperature loop is... The integral coefficient of the temperature loop is... Sampling period; temperature error The calculation formula is as follows:

[0082] ;

[0083] in, The temperature collected at the current PID calculation moment. The desired temperature is set for the host computer.

[0084] In step (5), the steady-state feedforward current The calculation formula is as follows:

[0085] ;

[0086] in, The Seebeck coefficient is... The resistance of the thermoelectric cooler. For the thermal conductivity of the cooling chip, The temperature of the hot surface of the cooling element; The desired temperature is set for the host computer.

[0087] Calculate the inner current loop:

[0088] ;

[0089] in, This is the proportionality coefficient of the current loop. The current error at the current moment. This represents the current error at the previous moment. The integral coefficient of the current loop is... These are the differential coefficients of the current loop. The sampling period is This is the output voltage required by the DAC circuit;

[0090] Current error at current moment The calculation formula is as follows:

[0091] ;

[0092] in, This represents the actual current collected at the current moment.

[0093] In summary, this invention uses a DAC output analog voltage to control the output voltage of the voltage output module instead of PWM control, preventing the problem of reduced lifespan of the cooler due to repeated thermal expansion and contraction of the cooler chips under frequent current switching. The design cost of this invention is lower than that of high-frequency PWM circuits. This invention can achieve temperature control of different coolers by controlling the cooler through multiple output voltages and monitoring the temperature of different coolers through an infrared thermal imaging module, thereby forming different temperature field outputs.

[0094] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection claimed by the appended claims and their equivalents is defined.

Claims

1. A temperature control device for an array-type semiconductor refrigeration chip, characterized in that: include: The power module provides the initial input voltage to power the voltage output module, the MCU main control module, and the thermoelectric array. The voltage output module is used to convert the initial input voltage to multiple 400mV to 6.6V voltages and output them to the thermoelectric array; Infrared thermal imaging module is used to acquire temperature signals of the cooling chips or objects on the cooling chips at different positions of the cooling chip array; The MCU main control module is used to control the multi-channel voltage output of the voltage output module, receive the multi-channel current signals collected by the voltage output module, receive the temperature signals collected by the infrared thermal imaging module, perform dual-loop PID calculations, and communicate with the host computer. A cooling chip array is used to receive multiple adjustable voltages from a voltage output module to achieve temperature control of the cooling chip or the object supported on the cooling chip in different areas. The host computer is used to communicate with the MCU main control module and set the temperature of different areas of the thermoelectric array.

2. The array-type semiconductor cooling chip temperature control device according to claim 1, characterized in that: The power supply module uses a switching power supply, model YX5603; the MCU main control module uses an STM32F104ZET6 controller; the infrared thermal imaging module is model MLX90642BAC; and the thermoelectric cooler array is model HT064304, using a 6×6 array.

3. The array-type semiconductor cooling chip temperature control device according to claim 1, characterized in that: The voltage output module includes a DAC circuit, a multi-channel adjustable buck circuit, and a current sampling circuit. The DAC circuit is connected to the multi-channel adjustable buck circuit, which is connected to the current sampling circuit. Simultaneously, the DAC circuit and the current sampling circuit are connected to the MCU main control module. The multi-channel adjustable buck circuit needs to be connected to a power supply module and a thermoelectric cooler array. The DAC circuit includes a DAC chip U2, capacitors C8 and C9. The DAC chip U2 uses a BH2221FV chip. The power supply terminal VCC of the BH2221FV chip is connected to the 3V3 power supply provided by the MCU main control module through capacitor C8, and the analog power input terminal VDD of the BH2221FV chip is connected to the 3V3 power supply provided by the MCU main control module through capacitor C9. The DAC chip provides multiple analog voltage output terminals, VO1 to VO12, which are connected to the multi-channel adjustable buck circuit of the voltage output module for outputting multiple voltages. The communication port of the DAC chip U2 is connected to the second communication port of the MCU control module for communication with the MCU control module, thereby controlling the output voltage value of the DAC circuit. The multi-channel adjustable buck circuit consists of multiple adjustable buck circuits with identical structures. Each adjustable buck circuit includes a DC-DC power chip U1, capacitors C1, C2, C3, C4, C5, C6, and C7, resistors R1, R2, and R3, diodes D1 and D2, inductor L1, and current sampling resistor R4. The DC-DC power chip U1 uses a YX5603 chip. The initial input voltage of the power module is connected to the power input pin VIN of the DC-DC power chip U1 through parallel capacitors C1, C2, and C3. The output pin SW of the DC-DC power chip U1 is connected in series with inductor L1 and then in parallel with capacitors C4, C5, and C6 as the positive terminal of the voltage output. One end of the current sampling resistor R4 is grounded, and the current sampling resistor R... The other end of 4 serves as the negative terminal of the voltage output terminal; the enable terminal EN of the DC-DC power chip U1 is connected to the multi-channel enable output terminal of the MCU control module; the feedback pin FB of the DC-DC power chip U1 is connected to resistors R1, R2, and R3 respectively; the other end of resistor R1 is connected to one end of inductor L1 and capacitor C6 respectively; capacitors C6, C5, and C4 are connected in parallel and share a common ground; the other end of inductor L1 is connected to the SW pin of the DC-DC power chip U1, capacitor C7, and the cathode of diode D1 respectively; the anode of diode D1 is grounded; the other end of capacitor C7 is connected to the BST pin of the DC-DC power chip U1; resistor R3 is connected to the cathode of diode D2; and the anode of diode D2 is connected to the output voltage VO1 of the DAC circuit.

4. The array-type semiconductor cooling chip temperature control device according to claim 1, characterized in that: The cooling chip array includes an alumina ceramic plate, multiple semiconductor cooling chips, a cooling fan, a connecting circuit board, and a support mold. The multiple semiconductor cooling chips are attached to the alumina ceramic plate with silicone grease to form an array. The two wires of the semiconductor cooling chips are connected to the connecting circuit board through holes in the alumina ceramic plate. The support mold is used to assemble the connecting circuit board, the cooling fan, and the alumina ceramic plate.

5. The array-type semiconductor cooling chip temperature control device according to claim 3, characterized in that: The adjustable step-down circuit's output voltage range is achieved by controlling the values ​​of resistors R1, R2, and R3, which affect the output voltage of the DAC circuit. When it is 0, to ensure the maximum output value It must satisfy the following formula: ； in, The reference voltage value for the feedback pin of the DC-DC power supply chip U1; When the maximum value is 3.3V, to ensure the minimum output value is The following formula must be satisfied: 。 6. The array-type semiconductor cooling chip temperature control device according to claim 3, characterized in that: The current sampling circuit includes an analog switch U3, a current sensing amplifier U4, capacitors C10 and C11. The analog switch U3 uses a 74HC4067PW chip, and the current sensing amplifier U4 uses an INA226 chip. The power input pin VCC of the analog switch U3 is connected to the 3V3 power supply provided by the MCU control module through capacitor C10, and the power input pin VCC of the current sensing amplifier U4 is connected to the 3V3 power supply provided by the MCU control module through capacitor C11. The multiple switch input pins Y1 to Y9 of the analog switch U3 are respectively connected to the negative terminal of the voltage output of each channel in the multi-channel adjustable step-down circuit of the voltage output module. The switch output pin Z is connected to the input pin VIN+ of the current sensing amplifier U4. The strobe signal pins S0 to S3 are connected to the analog switch control output terminal of the MCU control module. The communication ports SDA and SCL of the current sensing amplifier U4 are connected to the third communication port of the MCU control module for communication with the MCU control module, thereby transmitting the acquired current signal.

7. The control method of the array-type semiconductor refrigeration chip temperature control device according to any one of claims 1 to 6, characterized in that: The method includes the following steps in sequence: (1) Set the target area and target temperature to be controlled on the host computer and transmit them to the MCU main control module; (2) The infrared thermal imaging module collects the temperature of the cooling chip or the item on the chip in the target area and transmits it to the MCU main control module; (3) The MCU main control module adopts a dual-loop PID algorithm to calculate the outer loop temperature loop and obtain the target output current. ; (4) The MCU main control module collects the current flowing through the cooling chip in the target area; (5) The MCU main control module calculates the steady-state feedforward current. A dual-loop PID algorithm is used to calculate the inner current loop and obtain the output voltage required by the DAC circuit. And control the DAC circuit output of the voltage output module. ; (6) Each time time elapses Repeat steps (2) to (5).

8. The control method of the array-type semiconductor refrigeration chip temperature control device according to claim 7, characterized in that: In step (3), the target output current The calculation formula is: ； in, This indicates the current time of PID calculation. This indicates the time of the previous PID calculation. This is the temperature loop proportionality coefficient. The temperature error calculated at the current moment. This represents the temperature error from the previous moment. The integral coefficient of the temperature loop is... The integral coefficient of the temperature loop is... Sampling period; temperature error The calculation formula is as follows: ； in, The temperature collected at the current PID calculation moment. The desired temperature is set for the host computer.

9. The control method of the array-type semiconductor refrigeration chip temperature control device according to claim 7, characterized in that: In step (5), the steady-state feedforward current The calculation formula is as follows: ； in, The Seebeck coefficient is... The resistance of the thermoelectric cooler. For the thermal conductivity of the cooling chip, The temperature of the hot surface of the cooling element; The desired temperature is set for the host computer. Calculate the inner current loop: ； in, This is the proportionality coefficient of the current loop. The current error at the current moment. This represents the current error at the previous moment. The integral coefficient of the current loop is... These are the differential coefficients of the current loop. The sampling period is This is the output voltage required by the DAC circuit; Current error at current moment The calculation formula is as follows: ； in, This represents the actual current collected at the current moment.

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