Thermoelectric refrigerating unit circuit, thermoelectric refrigerating unit and optical communication system

Abstract

The utility model provides a thermoelectric refrigerating unit circuit, a thermoelectric refrigerating unit and an optical communication system. The thermoelectric refrigerating unit circuit comprises a DCDC chip circuit, a TEC and an MOS tube circuit which are connected in sequence. Wherein the DCDC chip circuit is connected to the positive electrode of the TEC; the MOS tube circuit is connected to the negative electrode of the TEC; the DCDC chip circuit is used for outputting a first voltage to the TEC; the MOS tube circuit is used for outputting a second voltage to the TEC by controlling the on-off of an NMOS tube and a PMOS tube; and the TEC is used for realizing a refrigerating or heating function according to the current direction and the voltage difference formed by the first voltage and the second voltage. By building one DCDC chip and the MOS tube, two functions of refrigeration and heating are realized, the equipment is miniaturized, the production cost is greatly reduced, and the conversion efficiency of heating / refrigeration is higher.

Description

Technical Field

[0001] The present application relates to the technical field of integrated circuits, and in particular to a thermoelectric cooler circuit, a thermoelectric cooler and an optical communication system. Background Art

[0002] In recent years, the fifth generation mobile communication system 5G has become a hot topic in the communication industry and academia. As an important part of the communication field, optical modules pursue higher accuracy, better stability, and more efficient utilization. As one of the important technologies in optical modules, TEC provides more precise wavelength control for lasers to meet the needs of high reliability.

[0003] TEC (Thermoelectric Cooler) refers to a device that uses the thermal-electric effect of semiconductors to generate cooling. It is also called a thermoelectric cooler. It has the characteristics of no noise, no vibration, and no need for refrigerants. It has become the main component of temperature control circuits on the current market.

[0004] In the prior art, the TEC control circuit is usually composed of four MOS tubes (P&P MOS, N&N MOS), each of which requires a separate PWM signal to control the working voltage to achieve heating or cooling functions. The circuit is relatively complex and PCB occupies a large space. Utility Model Content

[0005] The purpose of the present application is to provide a thermoelectric cooler circuit, a thermoelectric cooler and an optical communication system, which realize both cooling and heating functions by building a DCDC chip and a MOS tube. While miniaturizing the equipment, it greatly reduces the production cost and has a more efficient heating / cooling conversion efficiency.

[0006] In a first aspect, the present application provides a thermoelectric cooler circuit, which includes: a DCDC chip circuit, a TEC and a MOS tube circuit connected in sequence; wherein the DCDC chip circuit is connected to the positive pole of the TEC; the MOS tube circuit is connected to the negative pole of the TEC; the DCDC chip circuit is used to output a first voltage to the TEC; the MOS tube circuit is used to output a second voltage to the TEC by controlling the on and off of the NMOS tube and the PMOS tube; the TEC is used to realize a cooling or heating function according to the current direction and the pressure difference formed by the first voltage and the second voltage.

[0007] Furthermore, when the NMOS tube is turned on and the PMOS tube is turned off, the pulse width modulation signal of the NMOS tube is adjusted so that the current direction flows from the positive electrode to the negative electrode of the TEC, and the TEC realizes the cooling function; when the PMOS tube is turned on and the NMOS tube is turned off, the pulse width modulation signal of the PMOS tube is adjusted so that the current direction flows from the negative electrode to the positive electrode of the TEC, and the TEC realizes the heating function.

[0008] Furthermore, the greater the voltage difference between the first voltage and the second voltage, the stronger the heating effect or the cooling effect.

[0009] Furthermore, the DCDC chip circuit includes: a DCDC chip, an inductor, four capacitors and four resistors.

[0010] Furthermore, the voltage input pin and the power indicator pin of the DCDC chip are connected to the power supply voltage end of the DCDC chip and one end of the first capacitor through the first resistor; the other end of the first capacitor is grounded; the inductor pin of the DCDC chip is connected to one end of the inductor; the other end of the inductor is connected to the positive pole of the TEC; the second capacitor, the second resistor, the third capacitor and the fourth capacitor are sequentially arranged in parallel between the output feedback pin of the DCDC chip and the other end of the inductor; the third resistor is connected between the second resistor and the third capacitor; the output feedback pin is also connected to the PWM signal end of the TEC through the fourth resistor.

[0011] Furthermore, the MOS tube circuit includes: a P&N MOS tube chip and a fifth resistor.

[0012] Furthermore, the MOS transistor circuit includes: a PMOS transistor, an NMOS transistor and a fifth resistor.

[0013] Furthermore, the first pin of the P&N MOS tube chip is grounded, the second pin is connected to the N tube PWM signal end and is grounded through the fifth resistor, the third pin and the eighth pin are connected to the negative pole of the TEC; the fourth pin is connected to the high level end; the fifth pin is connected to the P tube PWM signal end; the sixth pin and the seventh pin are connected to the negative pole of the TEC.

[0014] In a second aspect, the present application further provides a thermoelectric cooler, which includes the thermoelectric cooler circuit as described in the first aspect.

[0015] In a third aspect, the present application further provides an optical communication system, the optical communication system comprising the thermoelectric cooler as described in the second aspect.

[0016] In the thermoelectric cooler circuit, thermoelectric cooler and optical communication system provided by the present application, the thermoelectric cooler circuit includes: a DCDC chip circuit, a TEC and a MOS tube circuit connected in sequence; wherein the DCDC chip circuit is connected to the positive pole of the TEC; the MOS tube circuit is connected to the negative pole of the TEC; the DCDC chip circuit is used to output a first voltage to the TEC; the MOS tube circuit is used to output a second voltage to the TEC by controlling the on and off of the NMOS tube and the PMOS tube; the TEC is used to realize the cooling or heating function according to the current direction and the pressure difference formed by the first voltage and the second voltage. The present application realizes the two functions of cooling and heating by building a DCDC chip and a MOS tube. While miniaturizing the equipment, it greatly reduces the production cost and has a more efficient heating / cooling conversion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 A circuit diagram of a thermoelectric cooler circuit provided in an embodiment of the present application;

[0019] Figure 2 A circuit diagram of another thermoelectric cooler circuit provided in an embodiment of the present application;

[0020] Figure 3 A schematic diagram of a TEC heating and cooling pressure difference provided in an embodiment of the present application. DETAILED DESCRIPTION

[0021] The technical solution of the present application will be described clearly and completely below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0022] The existing TEC control circuit usually uses an H-bridge type composed of four MOS tubes (P&P MOS, N&N MOS), where the functions of the MOS tubes are as follows:

[0023] P1 and N2 are switch tubes: control the current direction, P2 and N1 are control tubes: change the PWM duty cycle to adjust the pressure difference between the two ends of TEC; heating and cooling principle: heating direction: current flows from TEC- to TEC+, and the heating effect is adjusted by the pressure difference. Cooling direction: current TEC+ flows to TEC-, and the cooling effect is adjusted by the pressure difference.

[0024] However, the inherent on-off characteristics of MOS tubes mean that each MOS tube needs a separate PWM signal control, that is, each MOS tube needs an independent PWM signal to control its on and off to achieve heating or cooling functions. Due to the use of discrete components, the circuit is more complex and requires more PCB area, which is not conducive to miniaturization and will also lead to a higher failure rate.

[0025] Based on this, the embodiments of the present application provide a thermoelectric cooler circuit, a thermoelectric cooler and an optical communication system, which are constructed by a DCDC chip and a MOS tube to realize both cooling and heating functions. While miniaturizing the equipment, the production cost is greatly reduced, and the heating / cooling conversion efficiency is more efficient.

[0026] To facilitate understanding of this embodiment, a thermoelectric cooler circuit disclosed in an embodiment of the present application is first introduced in detail.

[0027] Figure 1 A schematic diagram of a thermoelectric cooler circuit provided in an embodiment of the present application, the thermoelectric cooler circuit includes: a DCDC chip circuit 21, a TEC22 and a MOS tube circuit 23 connected in sequence; wherein the DCDC chip circuit 21 is connected to the positive electrode of TEC22; the MOS tube circuit 23 is connected to the negative electrode of TEC22; the DCDC chip circuit 21 is used to output a first voltage to TEC22; the MOS tube circuit 23 is used to output a second voltage to TEC22 by controlling the on and off of the NMOS tube and the PMOS tube; TEC22 is used to realize a cooling or heating function according to the current direction and the pressure difference formed by the first voltage and the second voltage.

[0028] Furthermore, when the NMOS tube is turned on and the PMOS tube is turned off, the pulse width modulation signal PWM_N of the NMOS tube is adjusted so that the current direction flows from the positive electrode to the negative electrode of the TEC, and the TEC can achieve a cooling function; when the PMOS tube is turned on and the NMOS tube is turned off, the pulse width modulation signal PWM_P of the PMOS tube is adjusted so that the current direction flows from the negative electrode to the positive electrode of the TEC, and the TEC achieves a heating function.

[0029] The greater the voltage difference between the first voltage and the second voltage, the greater the current, and the stronger the heating effect or cooling effect.

[0030] See also Figure 2As shown, the DCDC chip circuit includes: a DCDC chip, an inductor, four capacitors and four resistors. Specifically, the voltage input pin VIN and the power indicator pin PG of the DCDC chip are connected to the DCDC chip power supply voltage terminal VCC_TEC and one end of the first capacitor C1 through the first resistor R1; the other end of the first capacitor C1 is grounded; the inductor pin LX of the DCDC chip is connected to one end of the inductor L; the other end of the inductor L is connected to the positive electrode TEC+ of TEC; between the output feedback pin FB of the DCDC chip and the other end of the inductor L, the second capacitor C2, the second resistor R2, the third capacitor C3 and the fourth capacitor C4 are sequentially arranged in parallel; the third resistor R3 is connected between the second resistor R2 and the third capacitor C3; the output feedback pin FB is also connected to the PWM signal terminal PWM_TEC of TEC through the fourth resistor R4.

[0031] The pin correspondence is as follows:

[0032] FB: output feedback pin output feedback pin;

[0033] GND: Ground pin;

[0034] VIN: input pin voltage input pin;

[0035] LX: inductor pin;

[0036] EN: enable control enable control pin;

[0037] PG: power good indicator power indicator pin.

[0038] Furthermore, the MOS transistor circuit includes: a P&N MOS transistor chip and a fifth resistor R5. In some implementations, the MOS transistor circuit may also include: a separate PMOS transistor and NMOS transistor, and a fifth resistor.

[0039] Furthermore, the first pin 1 of the P&N MOS tube chip is grounded, the second pin 2 is connected to the N tube PWM signal terminal PWM_N, and is grounded through the fifth resistor R5, the third pin 3 and the eighth pin 8 are connected to the negative pole TEC- of TEC; the fourth pin 4 is connected to the high level terminal VCC_3V3; the fifth pin 5 is connected to the P tube PWM signal terminal PWM_P; the sixth pin 6 and the seventh pin 7 are connected to the negative pole TEC- of TEC.

[0040] 1. When the cooling function is required, the NMOS tube is turned on and the PMOS is turned off. By adjusting PMW_N, the current direction flows from TEC+ to TEC-, and the current size represents the cooling effect.

[0041] 2. When the heating function is required, PMOS is turned on and NMOS is turned off. The current is adjusted by controlling PWM_P so that the current flows from TEC- to TEC+, and the current size represents the heating effect.

[0042] See also Figure 3 The process of TEC heating and cooling is shown as follows:

[0043] TEC heating function: current flows from TEC- to TEC+;

[0044] PMOS working conditions VGS<0: VS=3.3V, VG<3.3V, VTEC+<VTEC-<3.3V;

[0045] NMOS does not work when VGS < 0: VS = 0V, VG = 0V;

[0046] TEC cooling function: current flows from TEC+ to TEC-;

[0047] PMOS non-working condition VGS>0: VS=3.3V, VG=3.3V, PWM=FFF;

[0048] NMOS working conditions VGS>0: VS=0V, VG>0V, 0V<VTEC-<VTEC+;

[0049] VTEC+=0.6 1+R104 / R107, the VTEC+ voltage can be changed by changing PWM_TEC.

[0050] 1. Size comparison:

[0051] The TEC circuit scheme in the prior art is as follows:

[0052] The size of the two PMOS pairs: 2mm*2mm;

[0053] The size of 2 NMOS pairs: 2mm*2mm;

[0054] The TEC circuit solution provided in the embodiment of the present application is as follows:

[0055] The size of 1 DCDC: 1.5mm*1.5mm;

[0056] The size of one NMOS pair: 2mm*2mm.

[0057] 2. Efficiency comparison:

[0058] As shown in Tables 1 and 2, respectively, the heating efficiency under the prior art and the heating efficiency of the solution of the embodiment of the present application are shown. By comparing the data, it can be seen that the cooling / heating efficiency of the solution provided by the embodiment of the present application is higher and the effect is better.

[0059] Table 1

[0060]

[0061] Table 2

[0062]

[0063]

[0064] In Table 1, the meanings of the column names are as follows:

[0065] MCU_PWM: corresponding PWM_P / PWM_N processing;

[0066] VCC_TEC: total input voltage;

[0067] Iin: total input current;

[0068] V_TEC: TEC operating voltage;

[0069] IO: TEC operating current;

[0070] Efficiency % = V_TEC*IO) / (VCC_TEC*Iin); that is, output power consumption / input power consumption. The meanings of the column names in Table 2 are as follows:

[0071] PWM value: corresponding PWM_P / PWM_N processing;

[0072] V_TEC: TEC operating voltage;

[0073] I_TEC: TEC operating current;

[0074] TEC power consumption = V_TEC*I_TEC;

[0075] IR+IT: total input current;

[0076] Vin: total input voltage;

[0077] Total power consumption = Vin*(IR+IT);

[0078] Efficiency = output power consumption / input power consumption.

[0079] From the above, it can be seen that the existing H-bridge TEC solution has a heating efficiency of about 75% and a cooling efficiency of about 73%. The TEC efficiency of the DCDC+P&NMOS solution has a heating efficiency of about 83% and a cooling efficiency of about 86%. The circuit provided in this embodiment simplifies the circuit, reduces the cost, and has a higher heating / cooling effect than the existing solution.

[0080] The embodiment of the present application provides a thermoelectric cooler circuit constructed by a DCDC chip + a P&N MOS tube, which realizes the change of the pressure difference between the two ends of the TEC chip by controlling the on or off state of the P&N MOS, thereby realizing the cooling or heating function. Specifically, it is as follows:

[0081] 1. When the cooling function is required, the NMOS tube is turned on and the PMOS is turned off. By adjusting PMW_N, the current direction flows from TEC+ to TEC-, and the current size represents the cooling effect.

[0082] 2. When the heating function is required, PMOS is turned on and NMOS is turned off. The current is adjusted by controlling PWM_P so that the current flows from TEC- to TEC+, and the current size represents the heating effect.

[0083] By controlling the on or off state of the P&N MOS, the two functions of cooling and heating are realized, which not only realizes the miniaturization of the equipment, but also greatly reduces the production cost and improves the conversion efficiency.

[0084] Thermoelectric cooler circuits constructed with the same type of DCDC chip + MOS tube are all alternative solutions of the utility model.

[0085] Based on the above circuit embodiment, an embodiment of the present application further provides a thermoelectric cooler, which includes the thermoelectric cooler circuit as described above.

[0086] Based on the above-mentioned thermoelectric cooler embodiment, an embodiment of the present application further provides an optical communication system, and the optical communication system includes the above-mentioned thermoelectric cooler.

[0087] The thermoelectric cooler and optical communication system provided in the embodiments of the present application have the same implementation principles and technical effects as those of the aforementioned circuit embodiments. For the sake of brief description, for parts not mentioned in this embodiment, reference may be made to the corresponding contents in the aforementioned circuit embodiments.

[0088] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0089] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A thermoelectric cooler circuit, characterized in that: The thermoelectric cooler circuit comprises: a DCDC chip circuit, a TEC and a MOS tube circuit connected in sequence; wherein the DCDC chip circuit is connected to the positive electrode of the TEC; and the MOS tube circuit is connected to the negative electrode of the TEC; The DCDC chip circuit is used to output a first voltage to the TEC; The MOS tube circuit is used to output a second voltage to the TEC by controlling the on and off of the NMOS tube and the PMOS tube; The TEC is used to achieve a cooling or heating function according to a current direction and a pressure difference formed by the first voltage and the second voltage.

2. The thermoelectric cooler circuit according to claim 1, characterized in that: When the NMOS tube is turned on and the PMOS tube is turned off, the pulse width modulation signal of the NMOS tube is adjusted so that the current flows from the positive electrode to the negative electrode of the TEC, and the TEC realizes the cooling function; When the PMOS tube is turned on and the NMOS tube is turned off, the pulse width modulation signal of the PMOS tube is adjusted so that the current flows from the negative electrode to the positive electrode of the TEC, and the TEC realizes the heating function.

3. The thermoelectric cooler circuit according to claim 1, characterized in that: The greater the voltage difference formed by the first voltage and the second voltage, the stronger the heating effect or the cooling effect.

4. The thermoelectric cooler circuit according to claim 1, characterized in that: The DCDC chip circuit includes: a DCDC chip, an inductor, four capacitors and four resistors.

5. The thermoelectric cooler circuit according to claim 4, characterized in that: The voltage input pin and the power indicator pin of the DCDC chip are connected to the power supply voltage end of the DCDC chip and one end of the first capacitor through a first resistor; the other end of the first capacitor is grounded; the inductor pin of the DCDC chip is connected to one end of the inductor; the other end of the inductor is connected to the positive electrode of the TEC; a second capacitor, a second resistor, a third capacitor and a fourth capacitor are sequentially arranged in parallel between the output feedback pin of the DCDC chip and the other end of the inductor; a third resistor is connected between the second resistor and the third capacitor; the output feedback pin is also connected to the PWM signal end of the TEC through a fourth resistor.

6. The thermoelectric cooler circuit according to claim 4, characterized in that: The MOS tube circuit includes: a P&N MOS tube chip and a fifth resistor.

7. The thermoelectric cooler circuit according to claim 4, characterized in that: The MOS tube circuit includes: a PMOS tube, an NMOS tube and a fifth resistor.

8. The thermoelectric cooler circuit according to claim 6, characterized in that: The first pin of the P&N MOS tube chip is grounded, the second pin is connected to the N tube PWM signal end and is grounded through the fifth resistor, the third pin and the eighth pin are connected to the negative pole of TEC; the fourth pin is connected to the high level end; the fifth pin is connected to the P tube PWM signal end; the sixth pin and the seventh pin are connected to the negative pole of TEC.

9. A thermoelectric cooler, characterized in that: The thermoelectric cooler comprises a thermoelectric cooler circuit as claimed in any one of claims 1 to 8.

10. An optical communication system, characterized in that: The optical communication system comprises the thermoelectric cooler according to claim 9.

Images