Thermoelectric cooler control circuit and electronic device

Abstract

The application provides a thermoelectric refrigerator control circuit and an electronic device, the thermoelectric refrigerator control circuit comprises a voltage regulating module, a voltage control chip, a drive control chip and a thermoelectric refrigerator module; the voltage regulating module is connected with the voltage control chip and the drive control chip respectively, and the voltage regulating module is used for outputting a first voltage signal to the voltage control chip; the drive control chip comprises 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 with the thermoelectric refrigerator module, and outputs a drive control signal to the thermoelectric refrigerator module according to the second voltage signal, so as to adjust the drive voltage of the thermoelectric refrigerator module.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of temperature control, and in particular to a thermoelectric cooler control circuit and an electronic device. BACKGROUND

[0002] At present, the thermoelectric cooler (TEC) is often driven by constant voltage, but with the change of temperature in the use process, the output power of the thermoelectric cooler will decrease, and the stable output power cannot be maintained. SUMMARY

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

[0004] In a first aspect, an embodiment of the present application provides a thermoelectric cooler control circuit applied to a hanging neck air conditioner or a portable fan, which comprises a voltage adjusting module, a voltage control chip, a driving control chip and a thermoelectric cooler module; the voltage control chip is connected with the voltage adjusting module and the driving control chip respectively, the voltage adjusting module is used to output a first voltage signal to the voltage control chip; the driving control chip comprises 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 with the thermoelectric cooler module, and outputs a driving control signal to the thermoelectric cooler module according to the second voltage signal, so as to adjust the driving voltage of the thermoelectric cooler module.

[0005] In a second aspect, an electronic device is provided, which comprises the thermoelectric cooler control circuit according to any one of the embodiments of the present application.

[0006] The voltage adjusting module and the voltage control chip are additionally arranged at the voltage input end of the driving control chip in the thermoelectric refrigerator control circuit provided by the above embodiment, the voltage control chip is connected with the voltage adjusting module and the driving control chip respectively, the voltage adjusting 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, 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 with the thermoelectric refrigerator module, and the driving control signal is output to the thermoelectric refrigerator module according to the second voltage signal, so as to adjust the driving voltage of the thermoelectric refrigerator module. In this way, the first voltage signal is output to the voltage control chip, so that the voltage control chip can control the second voltage signal output to the driving control chip in real time through the first voltage signal, the second voltage signal input to the driving control chip drives the thermoelectric refrigerator module, and thus the precise control of the voltage of the thermoelectric refrigerator module can be realized, and the problem that the thermoelectric refrigerator module cannot continuously output at the rated power due to the constant voltage driving can be avoided.

[0007] The electronic device provided by the above embodiment belongs to the same concept as the corresponding thermoelectric refrigerator control circuit embodiment, and thus has the same technical effects as the corresponding thermoelectric refrigerator control circuit embodiment, which will not be described herein again. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 FIG. 1 is a structural schematic diagram of a thermoelectric refrigerator control circuit in an embodiment of the present application;

[0009] Figure 2 FIG. 3 is a schematic diagram of a voltage control chip in an embodiment of the present application;

[0010] Figure 3 FIG. 4 is a schematic diagram of a driving control chip in an embodiment of the present application;

[0011] Figure 4 FIG. 5 is a schematic diagram of a thermoelectric refrigerator module in an embodiment of the present application;

[0012] Figure 5 FIG. 6 is a connection schematic diagram of a thermistor in an embodiment of the present application;

[0013] Figure 6 FIG. 7 is a structural schematic diagram of a thermoelectric refrigerator control circuit in another embodiment of the present application;

[0014] Figure 7 FIG. 8 is a signal waveform schematic diagram in an embodiment of the present application;

[0015] Figure 8 FIG. 9 is a structural schematic diagram of a thermoelectric refrigerator control circuit in still another embodiment of the present application;

[0016] Figure 9 Figure 2 is a schematic diagram of a thermoelectric refrigerator control circuit according to an embodiment of the present application;

[0017] Figure 10 Figure 3 is a schematic diagram of an output voltage detection module according to an embodiment of the present application;

[0018] Figure 11 Figure 4 is a schematic diagram of a thermoelectric refrigerator control circuit according to another embodiment of the present application;

[0019] Figure 12 Figure 5 is a schematic diagram of a thermoelectric refrigerator power dynamic adjustment circuit according to an embodiment of the present application.

[0020] BRIEF DESCRIPTION OF DRAWINGS

[0021] 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 refrigerator module; 5, temperature detection module; 6, output voltage detection module; 7, power detection module. DETAILED DESCRIPTION

[0022] The technical solutions of the present application will be further described in detail below in combination with the accompanying drawings and specific embodiments.

[0023] In order to make the purpose, technical solutions and advantages of the present application more clear, the present application will be further described in detail below in combination with the accompanying drawings, and the described embodiments should not be regarded as limiting the present application, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present application.

[0024] In the following description, the expression "some embodiments" describes a subset of all possible embodiments, and it should be noted that "some embodiments" can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict.

[0025] In the following description, the terms "first, second, third" are only to distinguish similar objects, and do not represent a specific order of the objects, and it can be understood that "first, second, third" can be interchanged in a specific order or sequence as allowed, 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 of the present application and the features in the embodiments can be combined with each other without conflict.

[0026] As Figure 1As shown, one embodiment of this application provides a thermoelectric cooler control circuit, which can be applied to neck 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.

[0027] The voltage control chip 2 is connected to the voltage regulation module 1 and the drive control chip 3 respectively. 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. 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.

[0028] Here, the voltage regulation module 1 is connected to the voltage control chip 2, and the voltage regulation module 1 can output a first voltage signal with the same or different voltage to the voltage control chip 2.

[0029] Therefore, in the thermoelectric cooler control circuit, a voltage regulation module 1 and a voltage control chip 2 are added to the voltage input terminal of the drive control chip 3. The voltage control chip 2 is connected to the voltage regulation module 1 and the drive control chip 3 respectively. 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. 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.

[0030] Thus, by outputting a 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. 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 thermoelectric cooler module 4 from being unable to continuously output at the rated power due to constant voltage drive.

[0031] Specifically, the voltage control chip 2 can be a TPS54202H chip, an ETA2847 chip, an ETA8121 chip, or an EG1192L chip, or other types of chips; no specific limitation is made here. The drive control chip 3 can be an SA8339 chip, an AM2837 chip, or an RZ7889-MS chip, or other types of chips; no specific limitation is made here.

[0032] In one embodiment, the voltage control chip 2 further 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 regulate 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.

[0033] Thus, 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 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 thermoelectric cooler module 4 from being unable to continuously output at the rated power due to constant voltage drive.

[0034] Here, the feedback pin 21 is also connected to the switch pin 22 for acquiring the second voltage signal output by the switch pin 22.

[0035] In one embodiment, feedback pin 21 is represented as FB in voltage control chip 2. Feedback pin 21 is used to acquire the voltage signal output from switch pin 22 and the input first voltage signal. Switch pin 22 is represented as SW in voltage control chip 2. It 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 is represented as U1 and can be a DC-DC converter chip, such as a boost or buck DC-DC chip. Voltage control chip 2 can adjust the second voltage signal output from switch pin 22 in real time according to the first voltage signal and the second voltage signal acquired by feedback pin 21.

[0036] It is understandable that the second voltage signal output by switch pin 22 is the voltage input from voltage control chip 2 to drive control chip 3, which is the actual operating voltage of thermoelectric cooler module 4.

[0037] Table 1 shows the operating state of the thermoelectric cooler module 4 of an electronic device with a rated voltage of 5V without the application of the thermoelectric cooler control circuit of this application. Table 2 shows a schematic diagram of the operating state of the thermoelectric cooler module 4 of an electronic device with a rated voltage of 5V with the application of the thermoelectric cooler control circuit of this application.

[0038] Table 1: Schematic diagram of the operating status of the thermoelectric cooler module when the electronic device does not use the thermoelectric cooler control circuit of this application.

[0039]

[0040] Table 2: Schematic diagram of the working status of the thermoelectric cooler module when the thermoelectric cooler control circuit of this application is applied to electronic devices.

[0041]

[0042] From Table 1, we can clearly conclude that without the application of the thermoelectric cooler control circuit of this application, the actual operating voltage of the thermoelectric cooler module 4 in the electronic device cannot reach the rated voltage. Therefore, this results in poor temperature regulation of the thermoelectric cooler module 4.

[0043] From Table 2, we can clearly conclude that when using the thermoelectric cooler control circuit of this application, 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 changed according to the ambient temperature, thereby increasing the temperature regulation effect of the thermoelectric cooler module 4.

[0044] Furthermore, when the thermoelectric cooler control circuit of this application is applied, the thermoelectric cooler module 4 in the electronic device can operate at the rated voltage, thereby enabling the thermoelectric cooler module 4 to have a better cooling effect and a better temperature regulation capability, and can reduce the temperature more relative to the ambient temperature.

[0045] 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, i.e., the first voltage signal, to the feedback pin 21. For example, the voltage regulation module 1 may include a digital-to-analog converter (DAC) chip or DAC circuit for directly generating the first voltage signal. In some embodiments, the main control chip 11 may be a DAC8571 chip, an LTC1658 chip, or other types of chips, which are not limited here.

[0046] Alternatively, the voltage regulation module 1 may also include 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 pulse width modulation (PWM) form to the filtering module 12. The two ends of the filtering module 12 are respectively connected to the main control chip 11 and the feedback pin 21, and are used to filter the PWM form third voltage signal to obtain a first voltage signal, which is then output 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 other types of chips, which are not limited here.

[0047] The filtering module 12 includes at least one resistor and one capacitor connected in parallel, and can be connected to the feedback pin 21. The filtering module 12 can function as a low-pass filter, allowing low-frequency signals to pass through while attenuating or filtering out high-frequency signals. In PWM wave applications, high-frequency pulse components are filtered out, leaving only the average DC voltage related to the pulse width, i.e., a continuously stable first voltage signal.

[0048] In one embodiment, the feedback pin 21 can be connected to the switch pin 22 via a resistor, for example, the resistor can be used for voltage division, etc.

[0049] In one embodiment, such as Figure 2 As shown, voltage control chip 2 can be a step-down chip. 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. Switch pin 22 can also output a second voltage signal VCC_TEC1 to drive control chip 3 through an inductor L1, achieving step-down through inductor L1. The BST pin can be connected to switch pin 22 through a capacitor C2. The output terminal of switch pin 22, which outputs the second voltage signal to drive control chip 3, can also be grounded through a capacitor C2. FB and SW can be connected through a resistor R4.

[0050] In one embodiment, the thermoelectric cooler module 4 may include a TEC device for cooling or heating.

[0051] In one embodiment, such as Figure 3As shown, in IC1, IN_A and IN_B are the first and second level pins, respectively; OUT_A and OUT_B are output pins 32; GND represents the ground pin; TEC_A1 and TEC_B1 represent the nodes connected to the thermoelectric cooler module 4; voltage input pin 31 is represented as VCC; and output pins 32 are represented as OUT_A and OUT_B. The power supply pin VCC can be grounded through two capacitors C7 and C8, and voltage input pin 31 is connected to switch pin 22 for inputting the second voltage signal VCC_TEC1. The first and second level pins of the drive control chip 3 can be used to input enable signals T1+EN and T1-EN, respectively. The drive control chip 3 may include an H-bridge drive module. VCC_TEC supplies power to the drive control chip 3, and the high and low level combinations of T1+EN and T1-EN can be used to drive the thermoelectric cooler module 4 for cooling or heating.

[0052] For example, when T1+EN is high and T1-EN is low, the thermoelectric cooler module 4 heats. For example, when T1+EN is low and T1-EN is high, the thermoelectric cooler module 4 cools, etc., without specific limitations.

[0053] In one embodiment, such as Figure 4 As shown, the thermoelectric cooler module 4 may also include a negative temperature coefficient (NTC) thermistor.

[0054] In one embodiment, an NTC thermistor is represented as RT1 NTC. For example... Figure 5 As shown, the NTC thermistor can be grounded through a capacitor C6 and connected to the voltage regulation module 1 through a resistor R7.

[0055] The NTC thermistor is connected to the voltage regulation module 1, or it can be connected to the voltage regulation module 1 via the temperature detection module 5. The temperature detection module 5 can transmit the current or voltage signal output by the NTC thermistor as the detection result to the voltage regulation module 1. Alternatively, the temperature detection module 5 can detect the temperature of the NTC 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, which facilitates precise control of the first voltage signal output to the feedback pin 21, and thus facilitates precise control of the second voltage signal output to the drive control chip 3, improving power control accuracy.

[0056] In related technologies, the cooling or heating of a thermoelectric cooler is typically controlled by switching the output power polarity of the OUT_A and OUT_B pins of the driver IC (IC1) by controlling the high and low levels of the IN_A and IN_B pins. When the thermoelectric cooler is cooling or heating, the cooling or heating temperature is controlled by turning IC1 on and off, thereby controlling the power supply duration of the thermoelectric cooler and thus its power output. While this method is simple, it has the following drawbacks when frequently controlling the thermoelectric cooler's power on and off.

[0057] 1. Efficiency Loss (Switching Loss): During switching, IC1 contains an H-bridge circuit controlling the on / off state. This H-bridge consists of four Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs). MOSFETs experience a state where voltage and current coexist (in the linear region) at the instant of turn-on and turn-off. This generates significant switching losses, especially at higher switching frequencies. These losses are directly converted into heat, reducing the overall system efficiency. Efficiency losses are particularly noticeable at low duty cycles (low power output) because switching losses account for a larger proportion of the effective power transferred to the TEC. This necessitates a larger heatsink to cool the drive circuitry itself, increasing system size, weight, and cost; wasting battery energy (in portable devices); and reducing the system's maximum usable power.

[0058] Thermoelectric coolers in related technologies are basically driven by constant voltage. However, as the temperature changes during use, the output power of the thermoelectric cooler will decrease. Therefore, in order to maintain the rated power output of the thermoelectric cooler, pulse width modulation (PWM) control is usually used on the drive control chip 3 driving the thermoelectric cooler to maintain the output power. PPWM control of the IN_A and IN_B pins essentially involves repeatedly turning the chip on and off. However, the chip requires time to start and stop, and each start and stop requires energy, thus leading to delayed response and energy loss.

[0059] 2. Noise will be generated (audible noise and circuit noise): Audible noise: If the PWM frequency or its harmonics fall within the range of human hearing (20Hz - 20kHz), and the drive current is large enough, it may cause mechanical vibration of the connecting plates or ceramic substrate inside the thermoelectric cooler, producing a whistling sound. Although it can usually be avoided by choosing a frequency above 20kHz, higher frequencies will aggravate switching losses and electromagnetic interference (EMI).

[0060] Circuit noise: Because PWM control is used, the chip is essentially switching its switching transistors on and off repeatedly, which generates noise and causes a whistling sound.

[0061] In view of this, the drive control chip 3 in the aforementioned control circuit 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 being the opposite of the logic state of the first level signal.

[0062] Here, the first level pin can be represented as Figure 3 In the context of IN_A, the second-level pin can be represented as... Figure 3 In the IN_B input, 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 switching control via PWM waves. Dynamic adjustment can be achieved simply by receiving the second voltage signal from the voltage input pin 31. Furthermore, this method avoids power loss and howling noise caused by frequent power-on and power-off control of the thermoelectric cooler module 4, further improving the stability and availability of the thermoelectric cooler module 4.

[0063] The second level signal has the opposite logic state to the first level signal. This can mean that one of the second level signal and the first level signal is at a low level, while the other is at a high level.

[0064] For example, the second level signal is high and the first level signal is low. Or, the first level signal is high and the second level signal is low.

[0065] It is understood that in this application, continuous level signals are input to the first and second level pins. Therefore, the drive control chip 3 can be kept in a stable on-state, eliminating the need for repeated on and off switching. This avoids both the switching losses caused by repeatedly turning the drive control chip 3 on and off, and the whistling phenomenon caused by repeatedly switching the chip's switching transistors.

[0066] In some embodiments, such 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 pulse width modulation form 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.

[0067] Here, the filter module 12 is connected to the voltage control chip 2, which can be interpreted as being connected to the feedback pin 21. The third voltage signal in pulse width modulation (PWM) form can be generated by the main control chip 11 and transmitted to the filter module 12. The filter module 12 acts as a low-pass filter, allowing low-frequency signals to pass through while attenuating or filtering out high-frequency signals, resulting in a stable average DC voltage signal, i.e., the first voltage signal. Figure 7 As shown, curve a represents the third voltage signal in PWM form, and curve b represents the first voltage signal.

[0068] 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. The main control chip 11 can be connected to the feedback pin 21 of the voltage control chip 2 through the resistor. Thus, based on the resistor and capacitor, the PWM signal output by the main control chip 11 can be low-pass filtered to output a stable DC voltage signal.

[0069] In one embodiment, such as 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.

[0070] Here, the components included in the filter module 12 can form an RC integrator 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.

[0071] In one embodiment, the first resistor 121 is denoted as R1, the second resistor 122 is denoted as R2, and the first capacitor 124 is denoted as C1. The second resistor 122 and the third resistor 123 can achieve a voltage division effect on the second voltage signal, avoiding adverse effects on the chip or the drive control chip 3 due to excessive voltage.

[0072] Thus, by outputting a PWM wave through the main control chip 11 and filtering the PWM wave through the filtering module 12, a first voltage signal is generated to regulate the second voltage signal. This not only enables power control of the thermoelectric cooler module 4 but also reduces costs.

[0073] 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.

[0074] Here, connection to the voltage control chip 2 can refer to connection to the feedback pin 21. The feedback pin 21 is grounded through the third resistor 123, and the feedback pin 21 is connected to the switch pin 22 through the fourth resistor 125. The third resistor 123 is denoted as R3, and the fourth resistor 125 is denoted as R4. The second end of the second resistor 122 can be connected to both the feedback pin 21 and the third resistor 123. The fourth resistor 125 can be connected between the switch pin 22 and the feedback pin 21. For example, the first end of the inductor L1 is connected to the switch pin 22, and the second end is connected to the feedback pin 21 through the fourth resistor 125.

[0075] In one embodiment, such as 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. 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 on the feedback pin 21.

[0076] In this way, by connecting a voltage divider resistor between the switch pin 22 and the feedback pin 21, excessive voltage can be avoided, which may lead to insufficient control accuracy or adverse effects on the chip and the drive control chip 3.

[0077] 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.

[0078] Here, the DAC chip or DAC circuit in the digital-to-analog converter can directly generate a stable second voltage signal with high accuracy.

[0079] 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 characterizing 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.

[0080] Here, the temperature detection module 5 may include a detection chip, or it may only include a detection circuit, etc. The temperature detection module 5 can detect the temperature of the thermoelectric cooler module 4, and it can also detect the ambient temperature. The temperature feedback signal can characterize the temperature based on parameters such as voltage or current values, or it can directly carry a field representing the temperature value, etc.

[0081] In one embodiment, the voltage regulation module 1 adjusts the first voltage signal based on the temperature feedback signal, which can refer to the voltage regulation module 1 adjusting the first voltage signal based on the temperature value represented by the temperature feedback signal.

[0082] 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.

[0083] In this way, by adjusting the first voltage signal output to the feedback pin 21 of the voltage control chip 2 in real time according to the temperature of the thermoelectric cooler module 4, the second voltage signal output by the voltage control chip 2 to the drive control chip 3 can be adjusted more accurately, thereby precisely adjusting the TEC power and improving efficiency.

[0084] In some embodiments, the temperature detection module 5 is connected to the NTC thermistor in the thermoelectric cooler module 4.

[0085] Here, the thermistor can also be called a temperature resistor, etc. 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 voltage regulation module 1, or the temperature detection module 5 can detect the temperature of the NTC thermistor and send the temperature feedback signal characterizing the temperature to the voltage regulation module 1, etc.

[0086] For example, the main control chip 11 in the voltage regulation module 1 increases or decreases the voltage value of the first voltage signal based on 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.

[0087] 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.

[0088] 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 the filter module 12 outputs different first voltage signals, and the switch pin 22 outputs different second voltage signals.

[0089] In this way, the real-time temperature of the thermoelectric cooler module 4 can be determined more accurately and efficiently through the NTC thermistor, which is conducive to the precise control of the first voltage signal output to the feedback pin 21, and thus facilitates the precise control of the second voltage signal output to the drive control chip 3, thereby improving the power control accuracy.

[0090] In some embodiments, the thermoelectric cooler control circuit further 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 characterizing 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.

[0091] In one embodiment, connection to the voltage control chip 2 can refer to connection to 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 to acquire a second voltage signal, and the second end of the output voltage detection module 6 is connected to the voltage regulation module 1, such as... Figure 10 As shown.

[0092] In one embodiment, the voltage feedback signal can characterize the voltage value based on parameters such as different voltage or current values, or it can directly carry a field characterizing the voltage value. The voltage regulation module 1 adjusts the first voltage signal based on the voltage feedback signal, meaning the voltage regulation module 1 adjusts the first voltage signal based on the voltage value characterized by the voltage feedback signal.

[0093] 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.

[0094] In this way, the status of 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 to further improve accuracy.

[0095] In some embodiments, the thermoelectric cooler control circuit further 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 operating power of the thermoelectric cooler module 4 and send a power feedback signal characterizing the operating power to the voltage regulation module 1; the voltage regulation module 1 is used to adjust the first voltage signal based on the operating power.

[0096] For example, specific connection relationships can be as follows: Figure 11 As shown. The power feedback signal can characterize the operating power based on parameters such as different voltage or current values, or it can directly carry a field characterizing the operating power. The voltage regulation module 1 adjusts the first voltage signal based on the power feedback signal, which means that the voltage regulation module 1 adjusts the first voltage signal based on the operating power characterized by the power feedback signal.

[0097] 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.

[0098] In this way, the operating 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 to further improve the accuracy of power adjustment.

[0099] As one possible implementation, this application provides a dynamic power adjustment circuit for a thermoelectric cooler, such as... Figure 12 As shown, this power dynamic adjustment circuit can detect and dynamically adjust the power of the TEC (thermoelectric cooler module 4) in real time, thereby ensuring that the TEC power is constant. Dynamic adjustment of TEC power can make TEC temperature control more accurate and improve efficiency.

[0100] Specifically, a low-cost linear power supply method can be used to dynamically control the power of the TEC by changing the input voltage. The principle is to control the output voltage of the DC-DC chip (i.e., voltage control chip 2) to power the drive control chip 3 by controlling the voltage of its FB pin.

[0101] To control the voltage output of voltage control chip 2 (U1) to the desired voltage, the voltage of the FB pin of voltage control chip 2 needs to be adjusted. The function of the FB pin is to detect the output voltage and adjust it accordingly. To dynamically adjust the input voltage of the TEC, the output voltage of voltage control chip 2 needs to be adjusted by controlling the voltage of the FB pin, i.e., the output voltage output through the SW pin. The FB pin is the feedback pin 21, the SW pin is the switching pin 22, and DC-DC chip U1 is voltage control chip 2.

[0102] PWM wave, or Pulse Width Modulation signal, denoted as PWM1_TEC, is a modulation method that simulates a signal by changing the pulse width. Because PWM is a square wave with varying high and low voltage levels, it needs to be converted into a relatively stable voltage. When the PWM wave is input to the RC circuit, i.e., filter module 12, the filter module 12 acts as a low-pass filter, filtering out the high-frequency components in the PWM wave, thereby outputting a smoother DC voltage.

[0103] Here, the voltage value VFB of the feedback pin 21 (FB) of the voltage control chip 2 is related to the output voltage, i.e., the voltage value of the second voltage signal (VCC_TEC1). The voltage value VFB of the feedback pin 21 and the voltage value of the second voltage signal (VCC_TEC1) satisfy: VCC_TEC1 = VFB × (1 + R4 / R3), where R4 represents the resistance value of the fourth resistor 125 in the above formula, and R3 represents the resistance value of the third resistor 123 in the above formula.

[0104] Therefore, changing the voltage value VFB of the feedback pin 21 (FB) of the voltage control chip 2 will change the output voltage of the voltage control chip 2. 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 to 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, i.e., the second voltage signal, and inputting the second voltage signal to 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 inability of the thermoelectric cooler module 4 to continuously output rated power due to constant voltage drive.

[0105] 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 produce a stable voltage, or it can be output by the main control chip 11 as a PWM wave. Furthermore, the PWM input can be filtered using a filter circuit, i.e., the filter module 12.

[0106] The voltage control chip 2 can detect the voltage value of the feedback pin 21 and output different second voltage signals from the switch pin 22 according to the voltage value of the feedback pin 21. Therefore, the voltage value of the feedback pin 21 can be adjusted by outputting different first voltage signals through the voltage regulation module 1.

[0107] Optionally, a temperature detection module 5 connected to the main control chip 11 and the TEC can be included to detect the temperature of the TEC and transmit the temperature feedback signal as the detection result to the main control chip 11. The main control chip 11 can then adjust the voltage value of the first voltage signal according to the detection result. For example, the voltage can be increased when the temperature is greater than a threshold and decreased when the temperature is less than a threshold.

[0108] Optionally, it may also include a voltage detection module 6 output to the main control chip 11 and the voltage control chip 2, for detecting the voltage value of the second voltage signal output by the switch pin 22, and sending a voltage feedback signal representing the voltage value to the main control chip 11, and the main control chip 11 adjusting the voltage value of the first voltage signal based on the voltage value of the second voltage signal.

[0109] Optionally, it may also include a power detection module 7 connected to the TEC and the main control chip 11, for detecting the operating power of the TEC and sending a power feedback signal characterizing the operating power to the main control chip 11, and the main control chip 11 adjusting the voltage value of the first voltage signal based on the operating power.

[0110] This application also provides an electronic device, including the thermoelectric cooler control circuit described in any of the foregoing embodiments. The electronic device can be a neck air conditioner or a portable fan.

[0111] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0112] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A thermoelectric cooler control circuit, applied to neck 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 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. 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, characterized in that, The voltage control chip further includes a feedback pin and a switching pin. The feedback pin is connected to the voltage regulation module, and the voltage regulation module is used 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 based on the voltage of the feedback pin.

3. The thermoelectric cooler control circuit according to claim 1, characterized in that, 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 being the opposite of the logic state of the first level signal.

4. The thermoelectric cooler control circuit according to claim 1, characterized in that, The voltage regulation module includes: a main control chip and a filtering module; The main control chip is connected to the filtering module and is used to output a third voltage signal in pulse width modulation form to the filtering module; The two ends of the filtering 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 the first voltage signal and then output it to the voltage control chip.

5. The thermoelectric cooler control circuit according to claim 1, characterized in that, 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 used 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 further 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 characterizing the temperature to the voltage regulation module; the voltage regulation module is used to adjust 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 adjustment module; the voltage adjustment module is used to adjust 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 operating power of the thermoelectric cooler module and send a power feedback signal characterizing the operating power to the voltage regulation module; the voltage regulation module is used to adjust the first voltage signal based on the operating power.

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

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