Thermoelectric refrigerating unit control circuit and electronic equipment

Abstract

The invention provides a thermoelectric refrigerating unit control circuit and electronic equipment. The thermoelectric refrigerating unit control circuit comprises a voltage regulation module, a voltage control chip, a driving control chip and a thermoelectric refrigerating unit module, the voltage control chip is respectively connected with the voltage regulation module and the driving control chip, and the voltage regulation module is used for outputting a first voltage signal to the voltage control chip; the driving control chip comprises a voltage input pin and an output pin, and the voltage control chip outputs a second voltage signal to the voltage input pin based on the first voltage signal; and the output pin is connected with the thermoelectric refrigerating unit module and outputs a driving control signal to the thermoelectric refrigerating unit module according to the second voltage signal so as to adjust the driving voltage of the thermoelectric refrigerating unit module.

Description

Technical Field

[0001] The present application relates to the field of temperature control technology, and in particular to a thermoelectric cooler control circuit and electronic equipment. Background Art

[0002] Currently, thermoelectric coolers (TECs) are often driven by constant voltage. However, as the temperature changes during use, the output power of the TEC will decrease, making it impossible to maintain a stable output power. Summary of the Invention

[0003] In order to solve the existing technical problems, the present application provides a thermoelectric cooler control circuit and electronic equipment that can effectively maintain stable output power.

[0004] In the first aspect, an embodiment of the present application provides a thermoelectric cooler control circuit, which is applied to a neck-hanging air conditioner or a portable fan. The thermoelectric cooler control circuit includes: a voltage regulation module, a voltage control chip, a drive control chip and a thermoelectric cooler module; the voltage control chip is connected to the voltage regulation module and the drive control chip respectively, and the voltage regulation module is used to output a first voltage signal to the voltage control chip; the drive control chip includes a voltage input pin and an output pin, and the voltage control chip outputs a second voltage signal to the voltage input pin based on the first voltage signal; the output pin is connected to the thermoelectric cooler module, and outputs a drive control signal to the thermoelectric cooler module according to the second voltage signal to adjust the drive voltage of the thermoelectric cooler module.

[0005] In a second aspect, an electronic device is provided, comprising the thermoelectric cooler control circuit described in any embodiment of the present application.

[0006] In the thermoelectric cooler control circuit provided in the above embodiment, a voltage regulating module and a voltage control chip are added to the voltage input end of the drive control chip. The voltage control chip is connected to the voltage regulating module and the drive control chip, respectively. The voltage regulating module is used to output a first voltage signal to the voltage control chip. The drive control chip includes a voltage input pin and an output pin. The voltage control chip outputs a second voltage signal to the voltage input pin based on the first voltage signal. The output pin is connected to the thermoelectric cooler module and outputs a drive control signal to the thermoelectric cooler module based on the second voltage signal to adjust the drive voltage of the thermoelectric cooler module. In this way, by outputting the first voltage signal to the voltage control chip, the voltage control chip can control the second voltage signal output to the drive control chip in real time through the first voltage signal. The second voltage signal is input to the drive control chip to drive the thermoelectric cooler module, thereby achieving precise control of the voltage of the thermoelectric cooler module and avoiding the thermoelectric cooler module being unable to continuously output at the rated power due to constant voltage drive.

[0007] The electronic device provided by the above embodiment has the same concept as the corresponding thermoelectric cooler control circuit embodiment, and thus has the same technical effects as the corresponding thermoelectric cooler control circuit embodiment, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a structural diagram of a thermoelectric cooler control circuit in an embodiment of the present application; Figure 2 This is a schematic diagram of a voltage control chip in one embodiment of the present application; Figure 3 This is a schematic diagram of a drive control chip in one embodiment of the present application; Figure 4 Schematic diagram of a thermoelectric cooler module according to an embodiment of the present application; Figure 5 This is a connection diagram of a thermistor in one embodiment of the present application; Figure 6 This is a structural diagram of a thermoelectric cooler control circuit in another embodiment of the present application; Figure 7 A schematic diagram of signal waveforms in an embodiment of the present application; Figure 8 This is a structural diagram of a thermoelectric cooler control circuit in another embodiment of the present application; Figure 9 This is a structural diagram of a thermoelectric cooler control circuit in yet another embodiment of the present application; Figure 10 Schematic diagram of an output voltage detection module in one embodiment of the present application; Figure 11 This is a structural diagram of a thermoelectric cooler control circuit in another embodiment of the present application; Figure 12 FIG. 1 is a schematic diagram of a thermoelectric cooler power dynamic adjustment circuit according to an embodiment of the present application.

[0009] Description of Reference Numerals 1. Voltage regulation module; 11. Main control chip; 12. Filter module; 121. First resistor; 122. Second resistor; 123. Third resistor; 124. First capacitor; 125. Fourth resistor; 2. Voltage control chip; 21. Feedback pin; 22. Switch pin; 3. Drive control chip; 31. Voltage input pin; 32. Output pin; 4. Thermoelectric cooler module; 5. Temperature detection module; 6. Output voltage detection module; 7. Power detection module. DETAILED DESCRIPTION

[0010] The technical solution of this application is further elaborated in detail below with reference to the accompanying drawings and specific embodiments.

[0011] In order to make the purpose, technical solutions and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. The described embodiments should not be regarded as limiting this application. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0012] In the following description, the expression "some embodiments" is involved, which describes a subset of all possible embodiments. It should be noted that "some embodiments" may be the same subset or different subsets of all possible embodiments, and may be combined with each other without conflict.

[0013] In the following description, the terms "first, second, and third" are used merely to distinguish similar objects and do not represent a specific ordering of the objects. It is understood that "first, second, and third" can be interchanged with the specific order or sequence where permitted, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. It should be noted that the embodiments and features of the embodiments in the present application can be combined with each other unless there is a conflict.

[0014] like Figure 1 As shown, one embodiment of the present application provides a thermoelectric cooler control circuit, which can be applied to neck-hanging air conditioners or portable fans. The thermoelectric cooler control circuit includes: a voltage regulation module 1, a voltage control chip 2, a drive control chip 3, and a thermoelectric cooler module 4.

[0015] The voltage control chip 2 is connected to the voltage regulation module 1 and the drive control chip 3 respectively, and the voltage regulation module 1 is used to output a first voltage signal to the voltage control chip 2; the drive control chip 3 includes a voltage input pin 31 and an output pin 32, and the voltage control chip 2 outputs a second voltage signal to the voltage input pin 31 based on the first voltage signal; the output pin 32 is connected to the thermoelectric cooler module 4, and outputs a drive control signal to the thermoelectric cooler module 4 according to the second voltage signal to adjust the drive voltage of the thermoelectric cooler module 4.

[0016] Here, the voltage regulating module 1 is connected to the voltage control chip 2 , and the voltage regulating module 1 can output a first voltage signal with the same or different voltage to the voltage control chip 2 .

[0017] Therefore, in the thermoelectric cooler control circuit, a voltage regulating module 1 and a voltage control chip 2 are additionally provided at the voltage input end of the driving control chip 3. The voltage control chip 2 is connected to the voltage regulating module 1 and the driving control chip 3, respectively. The voltage regulating module 1 is used to output a first voltage signal to the voltage control chip 2; the driving control chip 3 includes a voltage input pin 31 and an output pin 32, and the voltage control chip 2 outputs a second voltage signal to the voltage input pin 31 based on the first voltage signal; the output pin 32 is connected to the thermoelectric cooler module 4, and outputs a driving control signal to the thermoelectric cooler module 4 according to the second voltage signal to adjust the driving voltage of the thermoelectric cooler module 4.

[0018] In this way, by outputting the first voltage signal to the voltage control chip 2, the voltage control chip 2 can control the second voltage signal output to the drive control chip 3 in real time through the first voltage signal. The second voltage signal is input to the drive control chip 3 to drive the thermoelectric cooler module 4, thereby achieving precise control of the voltage of the thermoelectric cooler module 4 and avoiding the constant voltage drive causing the thermoelectric cooler module 4 to be unable to continuously output at the rated power.

[0019] The voltage control chip 2 may be a TPS54202H chip, an ETA2847 chip, an ETA8121 chip, an EG1192L chip, or any other type of chip, and is not limited thereto. The drive control chip 3 may be a SA8339 chip, an AM2837 chip, an RZ7889-MS chip, or any other type of chip, and is not limited thereto.

[0020] In one embodiment, the voltage control chip 2 also includes a feedback pin 21 and a switch pin 22. The feedback pin 21 is connected to the voltage regulation module 1. The voltage regulation module 1 is used to output the first voltage signal to the feedback pin 21 to adjust the voltage of the feedback pin 21; the voltage control chip 2 detects the voltage of the feedback pin 21 and outputs the second voltage signal to the voltage input pin 31 through the switch pin 22 according to the voltage of the feedback pin 21.

[0021] In this way, by outputting a first voltage signal to the feedback pin 21 of the voltage control chip 2, the voltage control chip 2 can control the switch pin 22 in real time through the second voltage signal based on the second voltage signal output by the feedback pin 21. The second voltage signal is input to the drive control chip 3 to output a drive control signal to drive the thermoelectric cooler module 4, thereby achieving precise control of the voltage of the thermoelectric cooler module 4 and avoiding the constant voltage drive causing the thermoelectric cooler module 4 to be unable to continuously output at the rated power.

[0022] Here, the feedback pin 21 is also connected to the switch pin 22 for collecting the second voltage signal output by the switch pin 22 .

[0023] In one embodiment, feedback pin 21, represented as FB in voltage control chip 2, is used to collect the voltage signal output by switch pin 22 and input a first voltage signal. Switch pin 22, represented as SW in voltage control chip 2, is used to output a second voltage signal to drive control chip 3 to control the drive control signal output by drive control chip 3. The drive control signal is used to drive thermoelectric cooler module 4 for cooling or heating. Voltage control chip 2, represented as U1, can be a direct current (DC-DC) converter (DC-DC) chip, such as a step-up or step-down DC-DC chip. Voltage control chip 2 can adjust the second voltage signal output by switch pin 22 in real time based on the first voltage signal and the second voltage signal collected by feedback pin 21.

[0024] It can be understood that the second voltage signal output by the switch pin 22 is the voltage input from the voltage control chip 2 to the drive control chip 3 , which is the actual working voltage of the thermoelectric cooler module 4 .

[0025] Table 1 shows the operating status of the thermoelectric cooler module 4 of an electronic device with a rated voltage of 5V when the thermoelectric cooler control circuit of the present application is not applied. Table 2 shows the operating status of the thermoelectric cooler module 4 of an electronic device with a rated voltage of 5V when the thermoelectric cooler control circuit of the present application is applied.

[0026] Table 1: Schematic diagram of the working status of the thermoelectric cooler module when the electronic device does not apply the thermoelectric cooler control circuit of the present application.

[0027]

[0028] Table 2: Schematic diagram of the working states of the thermoelectric cooler module when the thermoelectric cooler control circuit of the present application is applied to an electronic device.

[0029]

[0030] From Table 1, we can undoubtedly conclude that without the thermoelectric cooler control circuit of the present application, the actual operating voltage of the thermoelectric cooler module 4 in the electronic device cannot reach the rated voltage. Therefore, the temperature control effect of the thermoelectric cooler module 4 is poor.

[0031] From Table 2, we can undoubtedly conclude that when the thermoelectric cooler control circuit of the present application is applied, the actual operating voltage of the thermoelectric cooler module 4 in the electronic device can be precisely controlled by the voltage control module. The actual operating voltage of the thermoelectric cooler module 4 can be adjusted according to the ambient temperature, thereby enhancing the temperature control effect of the thermoelectric cooler module 4.

[0032] Moreover, when the thermoelectric cooler control circuit of the present application is applied, the thermoelectric cooler module 4 in the electronic device can reach the rated voltage to operate, so that the thermoelectric cooler module 4 has a better cooling effect. The thermoelectric cooler module 4 has a better temperature regulation capability and can reduce the temperature more relative to the ambient temperature.

[0033] In one embodiment, the voltage regulation module 1 is connected to the feedback pin 21 and can output a continuous and stable DC voltage signal, namely a first voltage signal, to the feedback pin 21. For example, the voltage regulation module 1 can include a digital-to-analog converter (DAC) chip or DAC circuit to directly generate the first voltage signal. In some embodiments, the main control chip 11 can be a DAC8571 chip, an LTC1658 chip, or other chip models, without limitation herein.

[0034] Alternatively, the voltage regulation module 1 may also include a main control chip 11 and a filter module 12, wherein the main control chip 11 is connected to the filter module 12 and is configured to output a third voltage signal in the form of pulse width modulation (PWM) to the filter module 12. The two ends of the filter module 12 are respectively connected to the main control chip 11 and the feedback pin 21, and are configured to filter the third voltage signal in the form of PWM to obtain a first voltage signal and then output it to the feedback pin 21. The main control chip 11 may be a microcontroller unit (MCU), etc. In some embodiments, the main control chip 11 may be an STM32F103C8T6 chip, an STM32F4 chip, an MSP430F149 chip, etc., or may be other types of chips, which are not limited here.

[0035] The filter module 12 includes at least a resistor and a capacitor connected in parallel. The filter module 12 can be connected to the feedback pin 21. The filter module 12 functions as a low-pass filter, allowing low-frequency signals to pass while attenuating or filtering out high-frequency signals. In PWM wave applications, high-frequency pulse components are filtered out, leaving an average DC voltage related to the pulse width, i.e., a continuously stable first voltage signal.

[0036] In one embodiment, the feedback pin 21 may be connected to the switch pin 22 via a resistor. For example, the resistor may be used for voltage division.

[0037] In one embodiment, Figure 2 As shown, the voltage control chip 2 can be a step-down chip, and the voltage control chip 2 can also have a bootstrap pin BST, an input pin IN, a ground pin GND, and an enable pin EN. IN is used to input the power supply signal VBAT. For example, IN can be grounded through two capacitors C3 and C4 connected in parallel. The switch pin 22 can also output a second voltage signal VCC_TEC1 to the drive control chip 3 through an inductor L1, and the voltage is reduced by the inductor L1. The BST pin can be connected to the switch pin 22 through a capacitor C2, and the output end of the switch pin 22 that outputs the second voltage signal to the drive control chip 3 can also be grounded through a capacitor C2. A resistor R4 can be connected between FB and SW.

[0038] In one embodiment, the thermoelectric cooler module 4 may include a TEC device for cooling or heating.

[0039] In one embodiment, Figure 3As shown, in IC1, IN_A and IN_B are first-level and second-level pins, respectively; OUT_A and OUT_B are output pins 32; GND represents a ground pin; TEC_A1 and TEC_B1 represent nodes connected to the thermoelectric cooler module 4; voltage input pin 31 is represented by VCC; and output pins 32 are represented by OUT_A and OUT_B. The power supply pin VCC can be grounded via two capacitors C7 and C8. The voltage input pin 31 is connected to the switch pin 22 for inputting a second voltage signal VCC_TEC1. The first-level and second-level pins of the driver control chip 3 can be used to input enable signals T1+EN and T1-EN, respectively. The driver control chip 3 can include an H-bridge driver module. VCC_TEC supplies power to the driver control chip 3, and the high and low voltage combinations of T1+EN and T1-EN can be used to drive the thermoelectric cooler module 4 for cooling or heating.

[0040] For example, when T1+EN is high and T1-EN is low, the thermoelectric cooler module 4 generates heat. For example, when T1+EN is low and T1-EN is high, the thermoelectric cooler module 4 generates coolness, etc., which is not specifically limited here.

[0041] In one embodiment, Figure 4 As shown, the thermoelectric cooler module 4 may further include a negative temperature coefficient (NTC) thermistor.

[0042] In one embodiment, the NTC thermistor may be represented as RT1 NTC. Figure 5 As shown, the NTC thermistor can be grounded via a capacitor C6 and connected to the voltage regulation module 1 via a resistor R7.

[0043] The NTC thermistor is connected to the voltage regulation module 1, and can be connected to the voltage regulation module 1 through the temperature detection module 5. The temperature detection module 5 can transmit the current signal or voltage signal output by the NTC thermistor to the voltage regulation module 1 as the detection result. Alternatively, the temperature detection module 5 can detect the NTC temperature and transmit the temperature feedback signal as the detection result to the voltage regulation module 1. In this way, the real-time temperature of the thermoelectric cooler module 4 can be determined more accurately and efficiently through the NTC thermistor, thereby facilitating the precise control of the first voltage signal output to the feedback pin 21, which in turn facilitates the precise control of the second voltage signal output to the drive control chip 3, thereby improving the power control accuracy.

[0044] In related technologies, controlling the cooling or heating of a thermoelectric cooler typically involves controlling the high and low levels of the IN_A and IN_B pins of the driver control chip (IC) 3 (IC1), thereby switching the output power polarity of the driver IC's OUT_A and OUT_B pins. When the thermoelectric cooler is cooling or heating, the cooling or heating temperature is controlled by turning IC1 on or off to control the power-on and power-off durations of the thermoelectric cooler, thereby controlling the thermoelectric cooler's power. While this method is simple to control, it has the following disadvantages when frequently turning the thermoelectric cooler on and off.

[0045] 1. Efficiency Loss (Switching Losses): During the switching process, IC1's internal H-bridge circuit controls on / off. This H-bridge consists of four metal-oxide-semiconductor field-effect transistors (MOSFETs). MOSFETs experience a state of simultaneous voltage and current (in their linear region) during the on- and off-state transitions. This results in significant switching losses, especially at high switching frequencies. These losses are directly converted into heat, reducing overall system efficiency. Efficiency losses are particularly pronounced at low duty cycles (low power output), as switching losses contribute significantly to the effective power delivered to the TEC. This requires a larger heat sink to cool the driver circuitry, increasing system size, weight, and cost; wastes battery energy (in portable devices); and reduces the system's maximum available power.

[0046] Thermoelectric coolers in related technologies are generally driven by constant voltage, but as the temperature changes during use, the output power of the thermoelectric cooler decreases. Therefore, in order to maintain the rated power output of the thermoelectric cooler, pulse width modulation (PWM) is usually used on the driver control chip 3 that drives the thermoelectric cooler to maintain the output power. PWM control of the IN_A and IN_B pins essentially turns the chip on and off repeatedly. However, during the on-off and off-off process, the chip takes time to start and shut down, and each on-off and off-off requires energy, resulting in delayed response and energy loss.

[0047] 2. Noise (audible and circuit noise): Audible noise: If the PWM frequency or its harmonics fall within the audible range (20Hz-20kHz) and the drive current is high enough, it may cause mechanical vibrations in the thermoelectric cooler's internal connectors or ceramic substrate, resulting in a whistling sound. While this can usually be avoided by choosing a frequency above 20kHz, higher frequencies can increase switching losses and electromagnetic interference (EMI).

[0048] Circuit noise: Because PWM control is used, the chip is repeatedly turned on and off, which actually means the chip's switch tube is repeatedly turned on and off, which will generate noise and howling.

[0049] In view of this, the driving control chip 3 in the aforementioned control circuit also includes: a first level pin and a second level pin; the first level pin is used to input a continuous first level signal, and the second level pin is used to input a continuous second level signal, and the second level signal has an opposite logic state to the first level signal.

[0050] Here, the first level pin can be expressed as Figure 3 In IN_A, the second level pin can be expressed as Figure 3 In IN_B, the first level signal can be represented as T1+EN, and the second level signal can be represented as T1-EN. The first and second level pins input continuous level signals, eliminating the need for frequent PWM wave input for on-off control. Dynamic adjustment can be achieved simply by receiving the second voltage signal via voltage input pin 31. Furthermore, this approach avoids power loss and whistling noise caused by frequent power-on and power-off control of the thermoelectric cooler module 4, further improving the stability and usability of the thermoelectric cooler module 4.

[0051] The logic state of the second level signal is opposite to that of the first level signal, which may mean that one of the second level signal and the first level signal is at a low level and the other is at a high level.

[0052] For example, the second level signal is a high level, and the first level signal is a low level. Alternatively, the first level signal is a high level, and the second level signal is a low level.

[0053] It is understood that, in the present application, continuous level signals are input to the first level pin and the second level pin. Therefore, the driver control chip 3 can be kept in a stable on state without having to repeatedly turn the driver control chip 3 on and off. This can avoid switching losses caused by repeatedly turning the driver control chip 3 on and off, and can also avoid the phenomenon of howling caused by repeatedly turning the chip's switch tube on and off.

[0054] In some embodiments, as Figure 6 As shown, the voltage regulation module 1 includes: a main control chip 11 and a filtering module 12; the main control chip 11 is connected to the filtering module 12, and is used to output a third voltage signal in the form of pulse width modulation to the filtering module 12; the two ends of the filtering module 12 are respectively connected to the main control chip 11 and the voltage control chip 2, and are used to filter the third voltage signal to obtain a first voltage signal and then output it to the voltage control chip 2.

[0055] Here, the filter module 12 is connected to the voltage control chip 2, which can be connected to the feedback pin 21. The third voltage signal in the form of pulse width modulation, i.e., the PWM signal, can be generated by the main control chip 11 and transmitted to the filter module 12. The filter module 12 can act as a low-pass filter to allow low-frequency signals to pass through, while high-frequency signals are attenuated or filtered out, thereby obtaining a stable average DC voltage signal, i.e., the first voltage signal. Figure 7 As shown, curve a is the third voltage signal in PWM form, and curve b is the first voltage signal.

[0056] In one embodiment, the filtering module 12 can be a resistor-capacitor RC module, for example, including at least one resistor and one capacitor. The filtering module 12 is grounded through the capacitor, and the main control chip 11 can be connected to the feedback pin 21 of the voltage control chip 2 through the resistor, so that based on the resistor and the capacitor, the PWM signal output by the main control chip 11 can be low-pass filtered to output a stable DC voltage signal.

[0057] In one embodiment, Figure 8 As shown, the filtering module 12 includes: a first resistor 121, a second resistor 122 and a first capacitor 124; the first end of the first resistor 121 is connected to the main control chip 11, the second end of the first resistor 121 is connected to the first end of the second resistor 122, and the second end of the first resistor 121 is also grounded through the first capacitor 124; the second end of the second resistor 122 is connected to the feedback pin 21.

[0058] Here, the components included in the filter module 12 can form an RC integration circuit. Through the filtering effect of the filter module 12, the high-frequency components of the PWM wave are filtered out, and a relatively stable DC voltage is output.

[0059] In one embodiment, the first resistor 121 is represented by R1, the second resistor 122 is represented by R2, and the first capacitor 124 is represented by C1. The second resistor 122 and the third resistor 123 can achieve a voltage division effect on the second voltage signal to prevent excessive voltage from adversely affecting the chip or the driver control chip 3.

[0060] In this way, the main control chip 11 outputs a PWM wave, and the filter module 12 filters the PWM wave to generate a first voltage signal for adjusting the second voltage signal, which can achieve power control of the thermoelectric cooler module 4 and reduce costs.

[0061] In some embodiments, the thermoelectric cooler control circuit further includes: a third resistor 123 and a fourth resistor 125; the first end of the third resistor 123 is connected to the voltage control chip 2 and the second end of the fourth resistor 125 respectively, the second end of the third resistor 123 is grounded, and the first end of the fourth resistor 125 is connected to the voltage input pin 31.

[0062] Here, being connected to the voltage control chip 2 may refer to being connected to the feedback pin 21. The feedback pin 21 is grounded via the third resistor 123. The feedback pin 21 is connected to the switch pin 22 via the fourth resistor 125. The third resistor 123 is represented by R3, and the fourth resistor 125 is represented by R4. The second end of the second resistor 122 may be connected to the feedback pin 21 and the third resistor 123, respectively. The fourth resistor 125 may be connected between the switch pin 22 and the feedback pin 21. For example, the first end of the inductor L1 may be connected to the switch pin 22, and the second end may be connected to the feedback pin 21 via the fourth resistor 125.

[0063] In one embodiment, Figure 9 As shown, the voltage regulation module 1 includes: a main control chip 11 and a filter module 12, the first end of the fourth resistor 125 can be connected to the switch pin 22, for example, connected to the second end of the inductor L1, and the second end of the fourth resistor 125 can be connected between the filter module 12 and the feedback pin 21, that is, the fourth resistor 125 and the filter module 12 can be connected in parallel to the feedback pin 21.

[0064] In this way, by connecting a voltage divider resistor between the switch pin 22 and the feedback pin 21 , it is possible to avoid insufficient control accuracy caused by excessive voltage or adverse effects on the chip and the drive control chip 3 .

[0065] In some embodiments, the voltage regulation module 1 includes: a main control chip 11, which is a digital-to-analog converter; the digital-to-analog converter is connected to the feedback pin 21 and is used to output the first voltage signal to the voltage control chip 2.

[0066] Here, the DAC chip or DAC circuit in the digital-to-analog converter can directly generate a stable second voltage signal with high accuracy.

[0067] In some embodiments, the thermoelectric cooler control circuit further includes: a temperature detection module 5 connected to the voltage regulation module 1 and the thermoelectric cooler module 4; the temperature detection module 5 detects the temperature of the thermoelectric cooler module 4 and sends a temperature feedback signal representing the temperature to the voltage regulation module 1; the voltage regulation module 1 is used to adjust the first voltage signal based on the temperature feedback signal.

[0068] Here, the temperature detection module 5 may include a detection chip, or may only include a detection circuit, etc. The temperature detection module 5 can detect the temperature of the thermoelectric cooler module 4 and the ambient temperature. The temperature feedback signal can represent the temperature based on parameters such as voltage or current values, or can directly carry a field representing the temperature value.

[0069] In one embodiment, the voltage regulating module 1 regulates the first voltage signal based on the temperature feedback signal, which may mean that the voltage regulating module 1 regulates the first voltage signal based on the temperature value represented by the temperature feedback signal.

[0070] In one embodiment, the main control chip 11 adjusts the duty cycle of the PWM signal based on the temperature value represented by the temperature feedback signal, thereby outputting different first voltage signals through the filtering module 12 .

[0071] In this way, the first voltage signal output to the feedback pin 21 of the voltage control chip 2 is adjusted in real time according to the temperature of the thermoelectric cooler module 4, and the second voltage signal output by the voltage control chip 2 to the drive control chip 3 can be adjusted more accurately, thereby accurately adjusting the TEC power and improving efficiency.

[0072] In some embodiments, the temperature detection module 5 is connected to the NTC thermistor in the thermoelectric cooler module 4 .

[0073] Here, thermistor may also be referred to as a temperature resistor, etc. The temperature detection module 5 may transmit the current signal or voltage signal output by the NTC thermistor as a temperature feedback signal to the voltage regulation module 1. Alternatively, the temperature detection module 5 may detect the temperature of the NTC thermistor and transmit a temperature feedback signal representing the temperature to the voltage regulation module 1, etc.

[0074] For example, the main control chip 11 in the voltage regulation module 1 increases or decreases the voltage value of the first voltage signal according to the detection result. For example, the voltage is increased when the temperature of the thermoelectric cooler module 4 is greater than a predetermined threshold, and the voltage is decreased when the temperature is less than the predetermined threshold.

[0075] In one embodiment, the temperature detection module 5 can transmit the current signal or voltage signal output by the NTC thermistor as a temperature feedback signal to the main control chip 11, or the temperature detection module 5 can detect the NTC temperature and transmit the temperature feedback signal to the main control chip 11.

[0076] Here, the main control chip 11 adjusts the duty cycle of the PWM signal output to the filter module 12 based on the temperature feedback signal, so that different first voltage signals are output through the filter module 12, and the switch pin 22 outputs different second voltage signals.

[0077] In this way, the real-time temperature of the thermoelectric cooler module 4 can be determined more accurately and efficiently through the NTC thermistor, thereby facilitating the precise control of the first voltage signal output to the feedback pin 21, which in turn facilitates the precise control of the second voltage signal output to the drive control chip 3, thereby improving the power control accuracy.

[0078] In some embodiments, the thermoelectric cooler control circuit also includes: an output voltage detection module 6 connected to the voltage control chip 2 and the voltage regulation module 1; the output voltage detection module 6 is used to detect the voltage value of the second voltage signal and send a voltage feedback signal representing the voltage value to the voltage regulation module 1; the voltage regulation module 1 is used to adjust the first voltage signal based on the voltage value.

[0079] In one embodiment, the connection with the voltage control chip 2 may refer to the connection with the switch pin 22. The output voltage detection module 6 may include a capacitor C5 and two resistors R5 and R6. The first end of the output voltage detection module 6 is connected to the switch pin 22 for obtaining the second voltage signal. The second end of the output voltage detection module 6 is connected to the voltage regulation module 1. Figure 10 shown.

[0080] In one embodiment, the voltage feedback signal may represent the voltage value based on different parameters such as voltage values ​​or current values, or may directly carry a field representing the voltage value. The voltage regulation module 1 regulating the first voltage signal based on the voltage feedback signal may refer to the voltage regulation module 1 regulating the first voltage signal based on the voltage value represented by the voltage feedback signal.

[0081] In one embodiment, the main control chip 11 adjusts the duty cycle of the PWM signal based on the voltage value represented by the voltage feedback signal, thereby outputting different first voltage signals through the filtering module 12 .

[0082] In this way, the second voltage signal output by the voltage control chip 2 can be detected in real time, and the first voltage signal output to the voltage control chip 2 can be dynamically adjusted, thereby further improving the accuracy.

[0083] In some embodiments, the thermoelectric cooler control circuit also includes: a power detection module 7 connected to the thermoelectric cooler module 4 and the voltage regulation module 1; the power detection module 7 is used to detect the working power of the thermoelectric cooler module 4 and send a power feedback signal representing the working power to the voltage regulation module 1; the voltage regulation module 1 is used to adjust the first voltage signal based on the working power.

[0084] For example, the specific connection relationship can be as follows Figure 11 As shown. The power feedback signal can represent the operating power based on different parameters such as voltage values ​​or current values, or can directly carry a field representing the operating power. The voltage regulation module 1 adjusts the first voltage signal based on the power feedback signal, which may refer to the voltage regulation module 1 adjusting the first voltage signal based on the operating power represented by the power feedback signal.

[0085] In one embodiment, the main control chip 11 adjusts the duty cycle of the PWM signal based on the working power represented by the power feedback signal, thereby outputting different first voltage signals through the filtering module 12 .

[0086] In this way, the working power of the thermoelectric cooler module 4 can be detected in real time, and the first voltage signal output to the voltage control chip 2 can be dynamically adjusted, thereby further improving the accuracy of power adjustment.

[0087] As a possible implementation method, the present application provides a thermoelectric cooler power dynamic adjustment circuit, such as Figure 12 As shown, the power dynamic adjustment circuit can detect the power of the TEC, i.e., the thermoelectric cooler module 4, in real time and adjust it dynamically, thereby ensuring that the TEC power is constant. The dynamic adjustment of the TEC power can make the TEC temperature control more accurate and the efficiency can be relatively improved.

[0088] Specifically, a low-cost linear power supply can be used to dynamically control the TEC's power by varying the input voltage. This is achieved by controlling the voltage on the FB pin of the DC-DC chip, or voltage control chip 2, to control the output voltage of the voltage control chip 2, which then powers the driver control chip 3.

[0089] To control the desired output voltage of voltage control chip 2 (U1), you need to adjust the voltage on its FB pin. The FB pin detects and adjusts the output voltage. To dynamically adjust the TEC's input voltage, you need to control the FB pin voltage to adjust the output voltage of voltage control chip 2, which is output via the SW pin. The FB pin is the feedback pin 21, the SW pin is the switch pin 22, and the DC-DC chip U1 is the voltage control chip 2.

[0090] PWM, or pulse-width modulation (PWM1_TEC), is a modulation method that simulates a signal by varying the pulse width. Because PWM is a square wave with varying levels of voltage, it must be converted into a relatively stable voltage. When the PWM wave is input into the RC circuit, filter module 12, it acts as a low-pass filter, removing high-frequency components from the PWM wave and outputting a smoother DC voltage.

[0091] Here, the voltage value VFB at the feedback pin 21 (FB) of the voltage control chip 2 is correlated with the output voltage, or the voltage value of the second voltage signal (VCC_TEC1). The voltage value VFB at the feedback pin 21 and the voltage value of the second voltage signal (VCC_TEC1) satisfy the following equation: VCC_TEC1 = VFB × (1 + R4 / R3), where R4 represents the resistance of the fourth resistor 125, and R3 represents the resistance of the third resistor 123.

[0092] Therefore, by changing the voltage value VFB of the feedback pin 21 (FB) of the voltage control chip 2, the output voltage of the voltage control chip 2 will be changed. VFB consists of two parts: the voltage value corresponding to the specifications of the voltage control chip 2 itself, and the first voltage signal input by the voltage regulation module 1. The method used here is to input different voltages to the feedback pin 21 of the voltage control chip 2, thereby changing the output voltage of the voltage control chip 2. Therefore, by changing the output voltage of the voltage control chip 2, that is, the second voltage signal, and inputting the second voltage signal into the drive control chip 3 to output a drive control signal to drive the thermoelectric cooler module 4, precise control of the voltage of the thermoelectric cooler module 4 can be achieved, avoiding the problem of the thermoelectric cooler module 4 being unable to continuously output at the rated power due to constant voltage drive.

[0093] The voltage input to the feedback pin 21 of the voltage control chip 2 can be generated by using a DAC chip or a complex DAC circuit to generate a stable voltage, or by outputting a PWM wave from the main control chip 11. Moreover, the PWM input can be filtered by a filter circuit, i.e., a filter module 12.

[0094] The voltage control chip 2 can detect the voltage value of the feedback pin 21 and output a different second voltage signal from the switch pin 22 according to the voltage value of the feedback pin 21. Thus, the voltage value of the feedback pin 21 can be adjusted by the voltage regulation module 1 outputting different first voltage signals.

[0095] Optionally, a temperature detection module 5 connected to the main control chip 11 and the TEC can detect the temperature of the TEC and transmit a temperature feedback signal as the detection result to the main control chip 11. The main control chip 11 increases or decreases the voltage value of the first voltage signal according to the detection result. For example, the voltage value can be increased when the temperature is greater than a threshold value, and decreased when the temperature is less than the threshold value.

[0096] Optionally, it can also include an output voltage detection module 6 connected to the main control chip 11 and the voltage control chip 2, which is used to detect the voltage value of the second voltage signal output by the switch pin 22, and send a voltage feedback signal representing the voltage value to the main control chip 11. The main control chip 11 adjusts the voltage value of the first voltage signal based on the voltage value of the second voltage signal.

[0097] Optionally, a power detection module 7 connected to the TEC and the main control chip 11 may also be included, which is used to detect the working power of the TEC and send a power feedback signal representing the working power to the main control chip 11. The main control chip 11 adjusts the voltage value of the first voltage signal based on the working power.

[0098] The present application also provides an electronic device comprising the thermoelectric cooler control circuit described in any of the aforementioned embodiments, wherein the electronic device may be a neck-hanging air conditioner or a portable fan.

[0099] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0100] The above are only specific embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A thermoelectric cooler control circuit, used in neck-hanging air conditioners or portable fans, characterized in that: include: Voltage regulation module, voltage control chip, drive control chip and thermoelectric cooler module; The voltage control chip is connected to the voltage regulating module and the drive control chip respectively, and the voltage regulating module is used to output a first voltage signal to the voltage control chip; The drive control chip includes a voltage input pin and an output pin. The voltage control chip outputs a second voltage signal to the voltage input pin based on the first voltage signal; the output pin is connected to the thermoelectric cooler module and outputs a drive control signal to the thermoelectric cooler module according to the second voltage signal to adjust the drive voltage of the thermoelectric cooler module.

2. The thermoelectric cooler control circuit according to claim 1, wherein: The voltage control chip further includes a feedback pin and a switch pin, wherein the feedback pin is connected to the voltage regulation module, and the voltage regulation module is configured to output the first voltage signal to the feedback pin to regulate the voltage of the feedback pin; The voltage control chip detects the voltage of the feedback pin, and outputs the second voltage signal to the voltage input pin through the switch pin according to the voltage of the feedback pin.

3. The thermoelectric cooler control circuit according to claim 1, wherein: The drive control chip further includes: a first level pin and a second level pin; the first level pin is used to input a continuous first level signal, and the second level pin is used to input a continuous second level signal, the second level signal having a logic state opposite to that of the first level signal.

4. The thermoelectric cooler control circuit according to claim 1, wherein: The voltage regulation module includes: a main control chip and a filter module; The main control chip is connected to the filter module and is used to output a third voltage signal in a pulse width modulation form to the filter module; Two ends of the filter module are connected to the main control chip and the voltage control chip respectively, and are used to filter the third voltage signal to obtain a first voltage signal and then output it to the voltage control chip.

5. The thermoelectric cooler control circuit according to claim 1, wherein: The voltage regulation module includes: a main control chip, which is a digital-to-analog converter; The digital-to-analog converter is connected to the voltage control chip and is configured to output the first voltage signal to the voltage control chip.

6. The thermoelectric cooler control circuit according to any one of claims 1 to 5, characterized in that: The thermoelectric cooler control circuit also includes: a third resistor and a fourth resistor; the first end of the third resistor is connected to the voltage control chip and the second end of the fourth resistor respectively, the second end of the third resistor is grounded, and the first end of the fourth resistor is connected to the voltage input pin.

7. The thermoelectric cooler control circuit according to any one of claims 1 to 5, characterized in that: The thermoelectric cooler control circuit further includes: a temperature detection module connected to the voltage regulation module and the thermoelectric cooler module; The temperature detection module is used to detect the temperature of the thermoelectric cooler module and send a temperature feedback signal representing the temperature to the voltage regulation module; the voltage regulation module is used to regulate the first voltage signal based on the temperature feedback signal.

8. The thermoelectric cooler control circuit according to any one of claims 1 to 5, characterized in that: The thermoelectric cooler control circuit further includes: an output voltage detection module connected to the voltage control chip and the voltage regulation module; The output voltage detection module is used to detect the voltage value of the second voltage signal and send a voltage feedback signal representing the voltage value to the voltage regulation module; the voltage regulation module is used to regulate the first voltage signal based on the voltage value.

9. The thermoelectric cooler control circuit according to any one of claims 1 to 5, characterized in that: The thermoelectric cooler control circuit further includes: a power detection module connected to the thermoelectric cooler module and the voltage regulation module; The power detection module is used to detect the working power of the thermoelectric cooler module and send a power feedback signal representing the working power to the voltage regulation module; the voltage regulation module is used to regulate the first voltage signal based on the working power.

10. An electronic device, characterized in that: A thermoelectric cooler control circuit comprising the thermoelectric cooler control circuit according to any one of claims 1 to 9.

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