Multi-channel PID temperature controller

Abstract

The utility model discloses a multichannel PID temperature controller, which comprises an MCU, a power supply module and a temperature control module, the power supply module and the temperature control module are respectively connected with the MCU, the power supply module is used for providing working voltage for the operation of the PID temperature controller, the power supply module comprises a heating signal conversion circuit for converting to obtain a heating signal power supply, and the temperature control module is connected with the MCU. The temperature control module comprises at least two heating signal output circuits, and the circuit structures of the at least two heating signal output circuits are the same. The input end of the heating signal output circuit is connected to the MCU, and the first load output end and the second load output end of the heating signal output circuit are connected to the positive electrode output end and the negative electrode output end of the heating signal conversion circuit respectively. The heating signal output circuits are electrically connected to a power switch loop of the external heating equipment, and the MCU independently controls the plurality of heating signal output circuits, so that the external heating equipment can be controlled to work.

Description

Technical Field

[0001] The utility model relates to the technical field of temperature control circuits, in particular to a multi-channel PID temperature controller. Background Art

[0002] The existing temperature controller for semiconductor molding equipment is single-channel control. In multi-channel temperature control applications such as semiconductor molding equipment, a large number of them are required, which not only requires a large installation space, but also cannot store and record temperature data. It does not have heater current detection, making it inconvenient to uniformly control and manage temperature. Utility Model Content

[0003] The purpose of the invention of the utility model is to provide a multi-channel PID temperature controller to address the above problems, which can support multi-channel temperature acquisition, control and storage and recording of temperature data.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is:

[0005] A multi-channel PID temperature controller includes an MCU, a power module and a temperature control module, wherein the power module and the temperature control module are respectively connected to the MCU, the power module is used to provide an operating voltage for the operation of the PID temperature controller, wherein the power module includes a heating signal conversion circuit to convert a heating signal power supply, and the temperature control module includes at least two heating signal output circuits, and the circuit structure of each of the at least two heating signal output circuits is the same. The input end of the heating signal output circuit is connected to the MCU, and the first load output end and the second load output end of the heating signal output circuit are respectively connected to the positive output end and the negative output end of the heating signal conversion circuit. Wherein:

[0006] The power module includes a 24V power supply, a 24V to 5V conversion circuit, a 24V to 12V conversion circuit, a 5V to 3.3V conversion circuit and a 3.3V power indication circuit. The 24V to 5V conversion circuit is connected to the 24V power supply to convert the DC24V voltage into a DC5V voltage to output a 5V power supply; the heating signal conversion circuit is a 24V to 12V conversion circuit, which is connected to the 24V power supply to convert the DC24V voltage into a DC12V voltage to output a heating signal power supply; the 5V to 3.3V conversion circuit is connected to the 24V to 5V conversion circuit to convert the DC5V voltage into a DC3.3V voltage to output a 3.3V power supply; the positive and negative input terminals of the 3.3V power indication circuit are respectively connected to the positive and negative output terminals of the 5V to 3.3V conversion circuit to indicate the voltage output state of the 5V to 3.3V conversion circuit.

[0007] One of the heating signal output circuits includes an optocoupler isolation circuit and a heating output indication circuit, the optocoupler isolation circuit includes a photocoupler U and an isolation resistor, the first input pin 1 of the photocoupler U is connected to the MCU through the isolation resistor, the second input pin 3 of the photocoupler U is grounded, the first load output pin 6 and the first load output pin 4 of the photocoupler U are respectively connected to the positive output terminal and the negative output terminal of the heating signal conversion circuit. In a preferred embodiment, the heating signal output circuit also includes a heating output indication circuit, the heating output indication circuit includes an indicator light LED and an indication resistor, and the external voltage output pin 5 of the photocoupler U is connected to the negative output terminal of the heating signal conversion circuit through the indicator light LED and the indication resistor in turn, so that it can play an indication role.

[0008] The beneficial effects of the utility model are as follows: the utility model converts the 24V power supply voltage into different voltage values ​​through the power module, which can provide the voltage power supply required for the operation of each power module in the temperature control driver, and as a heating signal output, effectively ensures the normal operation of the temperature control driver. In actual application, the utility model is electrically connected to the power switch circuit of the external heating device through the heating signal output circuit, and the external heating device can be controlled to work by controlling multiple heating signal output circuits separately through the MCU (outputting the heating signal to turn on the power switch). In this way, independent multi-channel temperature control can better meet the application occasions that require multi-channel temperature control than single-channel temperature control, reduce the number of single-channel temperature controllers, and greatly save installation space.

[0009] Further, based on the aforementioned scheme, in an improved scheme, the heating signal output circuit also includes at least two current detection circuits, which are used in pairs with the heating signal output circuit, and the circuit structure of each of the at least two current detection circuits is the same, wherein one of the current detection circuits includes a current detection signal processing circuit and a current transformer, and the current transformer can be electrically connected to an external heating device, and the current detection signal processing circuit includes a rectification and I / V conversion circuit and a follower, and the output end of the current transformer is connected to the input end of the follower through the current detection signal processing circuit, and the output end of the follower is connected to the MCU, and the power pin of the follower is connected to a 5V power supply.

[0010] The beneficial effects of the above further scheme are as follows: the utility model obtains the working current signal of the external heating device through the current transformer, and the current detection signal processing circuit converts the current signal into a voltage signal and sends it to the MCU part for sampling and conversion to obtain the heater current value. In practical applications, the heater current and whether there is overcurrent or disconnection can be detected in real time.

[0011] Furthermore, based on the aforementioned scheme, in the improved scheme, the PID temperature controller also includes a temperature detection module, the temperature detection module includes at least two temperature detection circuits, the temperature detection circuit is used in pairs with the heating signal output circuit, and the circuit structure of each of the at least two temperature detection circuits is the same, one of the temperature detection circuits specifically includes a temperature signal input circuit and a temperature sensor, the temperature signal input circuit includes a bridge circuit and a differential amplifier circuit, and the output end of the temperature sensor is connected to the MCU through the bridge circuit and the differential amplifier circuit in turn.

[0012] The beneficial effect of the above further scheme is: the utility model obtains the temperature numerical signal of the temperature control object through the temperature sensor, and then transmits the temperature numerical signal to the MCU through the temperature signal input circuit, so as to achieve the purpose of detecting the temperature. In practical applications, the MCU can also convert the temperature difference according to the temperature preset value and the temperature numerical value, and then control the temperature control module and the corresponding heating signal output circuit to output the heating signal to the outside according to the temperature difference, and adjust the temperature of the temperature control object until the temperature value detected by the temperature sensor is within the range of the temperature preset value; the temperature signal input circuit uses a bridge plus a precision differential amplifier circuit, which can make the temperature detection accuracy higher and the temperature control more precise.

[0013] Further, based on the above scheme, in the improved scheme, the PID temperature controller also includes a communication module, the communication module includes an RS485 communication transceiver circuit, a CAN communication transceiver circuit and a USB communication interface circuit, wherein:

[0014] The RS485 communication transceiver circuit includes a communication chip U6, resistors R6-R10, capacitors C25-C28, fuses F2-F3 and an ESD static and surge protection circuit D4. The VCC pin 1 of the communication chip U6 is respectively connected to one end of the capacitor C25 and one end of the capacitor C26 and connected to the positive electrode of the 5V power supply. The GNDA pin 2 of the communication chip U6 is respectively connected to the other end of the capacitor C25 and the other end of the capacitor C26 and grounded. The RO pin 3, DE pin 5 and DI pin 6 of the communication chip U6 are respectively connected to one end of the resistor R6, one end of the resistor R7 and one end of the resistor R8. The other end of the resistor R6, the other end of the resistor R7 and the other end of the resistor R8 are respectively connected to the MCU. The RE pin 4 of the communication chip U6 is connected to the DE pin 5. The GNDA pin 7 of the communication chip U6 is connected to the GNDA pin 8 and grounded. The GNDB pin 9 of the communication chip U6 is respectively connected to the One end of capacitor C27, one end of capacitor C28 are connected to GNDB pin 15 of communication chip U6, SEL pin 10 of communication chip U6 is respectively connected to VISO pin 16 of communication chip U6, the other end of capacitor C27, the other end of capacitor C28 and one end of resistor R9, A pin 12 of communication chip U6 is respectively connected to the other end of resistor R9, pin 2 of ESD static and surge protection circuit D4 and one end of fuse F2, the other end of fuse F2 serves as the first transmission end of RS485, pin 13 of communication chip U6 is respectively connected to one end of resistor R10, pin 1 of ESD static and surge protection circuit D4 and one end of fuse F3, the other end of resistor R10 is connected to GNDB pin 9 of communication chip U6, the other end of fuse F3 serves as the second transmission end of RS485, pin 3 of ESD static and surge protection circuit D4 is connected to GNDB pin 9 of communication chip U6.

[0015] The CAN communication transceiver circuit includes a communication chip U7, capacitors C29-C32, resistors R15-R18, fuses F4-F5 and ESD static and surge protection circuit D5. The TXD pin 1, RXD pin 4, VIO pin 5 and STBY pin 8 of the communication chip U7 are respectively connected to one end of the resistor R15, one end of the resistor R16, one end of the resistor R18 and one end of the resistor R17. The other end of the resistor R15 and the other end of the resistor R16 are respectively connected to the MCU. The other end of the resistor R18 is connected to the positive electrode of the 3.3V power supply, and the other end of the resistor R17 is connected to the negative electrode of the 3.3V power supply. The VDD pin 3 of the communication chip U7 is respectively connected to one end of the capacitor C29, one end of the capacitor C30 and connected to 5 V power supply positive electrode, the other end of capacitor C29, the other end of capacitor C30 and VSS pin 2 of communication chip U7 are all connected to the negative electrode of 5V power supply, CANL pin 6 of communication chip U7 are respectively connected to pin 2 of ESD static and surge protection circuit D5, one end of capacitor C32 and one end of fuse F5, the other end of fuse F5 serves as the first transmission end of CAN, CANH pin 7 of communication chip U7 are respectively connected to pin 1 of ESD static and surge protection circuit D5, one end of capacitor C31 and one end of fuse F4, the other end of fuse F4 serves as the second transmission end of CAN, the other end of capacitor C32, the other end of capacitor C31 and pin 3 of ESD static and surge protection circuit D5 are all connected to the negative electrode of 3.3V power supply.

[0016] The USB communication interface circuit includes a communication chip USB1, resistors R117-resistor R118, capacitors C35-capacitor C36, fuse F7 and voltage-stabilizing diode D8. The VBUS pin 1 of the communication chip USB1 is respectively connected to one end of the capacitor C35, one end of the capacitor C36, fuse F7, voltage-stabilizing diode D8 and connected to the MCU. The other end of the capacitor C35 and the other end of the capacitor C36 are both grounded. The D- pin 2 and D+ pin 3 of the communication chip USB1 are respectively connected to one end of the resistor R118 and one end of the resistor R117. The other end of the resistor R118 and the other end of the resistor R117 are respectively connected to the MCU. The GND pin 4, GND pin 5 and GND pin 6 of the communication chip USB1 are all grounded.

[0017] Based on the above scheme, as a preferred scheme, the communication module also includes a terminal matching resistor selection circuit and a communication indication circuit. The terminal matching resistor selection circuit includes a switch SW1 and a resistor R13 and a resistor R14, and two independent paths are respectively set between pins 1 and 4 and pins 2 and 3 of the switch SW1, and pin 4 of the switch SW1 is connected to one end of the resistor R13, and the other end of the resistor R13 and the pin 1 of the switch SW1 are respectively connected to the B pin 13 and the A pin 12 of the communication chip U6 of the RS485 communication transceiver circuit, and the pin 3 of the switch SW1 is connected to one end of the resistor R14, and the other end of the resistor R14 and the pin 2 of the switch SW1 are respectively connected to the CAHH pin 6 and the CAHL pin 7 of the communication chip U7 of the CAN communication transceiver circuit, so that the RS485 communication terminal matching resistor circuit or the CAN communication terminal matching resistor circuit loop is turned on when the switch SW1 is in the switching state; in this way, it can be selected whether to connect the terminal matching resistor circuit in different communication connection environments. The communication indication circuit includes indicator light LED2-1, indicator light LED2-2 and resistor R11-resistor R12, one end of resistor R11 and one end of resistor R12 are respectively connected to the positive electrode of the 5V power supply, the other end of resistor R11 and the other end of resistor R12 are respectively connected to the positive electrode of indicator light LED2-1 and the positive electrode of indicator light LED2-2, the negative electrode of indicator light LED2-1 and the negative electrode of indicator light LED2-2 are respectively connected to the RO pin 3 of the communication chip U6 and the RXD pin 4 of the communication chip U7; the communication indication circuit is used for indicating the signal reception status of the RS485 communication transceiver circuit and the CAN communication transceiver circuit.

[0018] The beneficial effects of the above further scheme are: the utility model is connected to the terminal control device through the communication module for communication. In actual application, after the PID temperature controller is connected to the terminal control device, it can synchronously monitor the temperature value, heating status, etc. of each channel through the terminal control device, and can receive control instructions sent by the terminal control device, such as modifying the preset temperature value, stopping heating, etc.; the utility model also has RS485, CAN and USB communication functions, which meets the control of terminal control devices with different communication interfaces and meets the needs of more industry application fields.

[0019] Furthermore, based on the aforementioned scheme, in the improved scheme, the PID temperature controller also includes an emergency switch module, the emergency control module includes at least one external event trigger circuit, the circuit structure of each external event trigger circuit is the same, and one external event trigger circuit specifically includes a trigger switch, a resistor R19, a diode D6 and a photoelectric coupler OP1, the input pin 1 of the photoelectric coupler OP1 is respectively connected to the cathode of the diode D6 and one end of the resistor R19, the other end of the resistor R19 is connected to one end of the trigger switch, the other end of the trigger switch is respectively connected to the input pin 2 of the photoelectric coupler OP1 and the anode of the diode D6, the output pin 4 of the photoelectric coupler OP1 is connected to the MCU, and the output pin 3 of the photoelectric coupler OP1 is grounded.

[0020] The beneficial effect of the above further solution is that the utility model can handle emergency situations through the emergency control module, such as shutting down the heating output.

[0021] Further, based on the aforementioned scheme, in the improved scheme, the PID temperature controller also includes a data storage module, the data storage module includes a TF card interface circuit and a TF card, the TF card interface circuit includes resistors Rp1-resistance Rp2, capacitors C33-capacitor C34, inductor L5 and fuse F6, the DAT2 pin 1, DAT3 pin 2 and CMD pin 3 of the TF card are respectively connected to the three output pins of the resistor Rp2, the DAT0 pin 7, DAT1 pin 8 and CD pin 9 of the TF card are respectively connected to the three output pins of the resistor Rp1, the common pin of the resistor Rp1 is connected to the common pin of the resistor Rp2 and connected to the positive electrode of the 3.3V power supply, the VDD pin 4 of the TF card is respectively connected to one end of the capacitor C34 and one end of the inductor L5 through the fuse F6, the other end of the inductor L5 is connected to one end of the capacitor C33 and connected to the positive electrode of the 3.3V power supply, and the other end of the capacitor C34, the other end of the capacitor C33 and the VSS pin 6 of the TF card are all connected to the negative electrode of the 3.3V power supply.

[0022] The beneficial effect of the above further scheme is that the temperature sampling value of the temperature detection module can be recorded through the data storage module. In actual application, when the temperature value of the temperature control object exceeds the condition value, the data storage module can be triggered to record the current temperature value, which is convenient for subsequent operators to view.

[0023] Due to the adoption of the above technical solution, the utility model has the following beneficial effects:

[0024] 1. Multi-channel temperature control is adopted in terms of the number of channels, and each channel has independent temperature control. Compared with single-channel temperature control, it can better meet the application occasions that require multi-channel temperature control. It has the advantages of small size, saving installation space, and facilitating unified control and management.

[0025] Second, each channel has heater current detection, which can detect in real time whether the heater is over-current or broken, and improve temperature control efficiency.

[0026] 3. It has temperature detection function. The temperature sampling circuit uses a bridge plus a precision differential amplifier circuit, which makes the temperature detection accuracy high and the temperature control more precise.

[0027] 4. It has RS485, CAN, and USB communication functions, which can meet the control interaction of control devices with more communication interfaces and realize unified temperature management.

[0028] 5. It has the function of storing and recording temperature data, such as triggering the recording of temperature when the temperature exceeds the range.

[0029] 6. It has an external event trigger function, which can be used to handle emergency situations, such as shutting down the heating output. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a circuit diagram of the power module of the utility model.

[0031] Figure 2 It is a circuit diagram of the MCU of the utility model.

[0032] Figure 3 The utility model discloses a circuit diagram of a heating signal output circuit in a temperature control module.

[0033] Figure 4 It is a circuit diagram of an example of a heating signal controlling a heater in a temperature control module of the utility model.

[0034] Figure 5 It is a circuit diagram of the heating connection terminals CN3 and CN4 in the temperature control module of the utility model.

[0035] Figure 6 A circuit diagram of a heating output indicating circuit in a temperature control module of the utility model.

[0036] Figure 7 The utility model is a circuit diagram of a current detection signal processing circuit in a temperature control module.

[0037] Figure 8 The utility model is a circuit diagram of a temperature detection circuit in a temperature detection module.

[0038] Fig. 9 It is a circuit diagram of the temperature connection terminal CN5 in the temperature detection module of the present utility model.

[0039] Fig.10 The utility model is a circuit diagram of an auxiliary signal output circuit in a temperature detection module.

[0040] Fig.11 The utility model discloses a circuit diagram of an RS485 communication transceiver circuit in a communication module.

[0041] Fig.12 The utility model discloses a circuit diagram of a CAN communication transceiver circuit in a communication module.

[0042] Fig.13 It is a circuit diagram of the communication terminal CN2 in the communication module of the utility model.

[0043] Fig.14 The utility model discloses a circuit diagram of a USB communication interface circuit in a communication module.

[0044] Fig.15 The utility model discloses a circuit diagram of a communication indicating circuit in a communication module.

[0045] Fig.16 It is a circuit diagram of a selection circuit in a communication module of the utility model.

[0046] Fig.17 It is a circuit diagram of an external event triggering circuit in an emergency control module of the utility model.

[0047] Fig.18 It is a circuit diagram of a TF card interface circuit in a data storage module of the utility model. DETAILED DESCRIPTION

[0048] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0049] Example 1

[0050] A multi-channel PID temperature controller of the present embodiment 1 includes an MCU, a power module and a temperature control module, wherein the power module and the temperature control module are respectively connected to the MCU, and the power module is used to provide a working voltage and output a heating signal power supply for the operation of the PID temperature controller. In this application, the heating signal power supply is described as a 12V power supply as an example.

[0051] like Figure 1 As shown, the power module includes a 24V power supply, a 24V to 5V conversion circuit, a 24V to 12V conversion circuit, a 5V to 3.3V conversion circuit, a 3.3V power indication circuit and a 5V voltage stabilization circuit, wherein:

[0052] The circuit structure of the 24V to 5V conversion circuit includes a fuse F1, an anti-reverse connection diode D1, a common-mode differential-mode filter circuit composed of a polarity capacitor C1, capacitors C2, C3, C4, C5, C6, C7, C21, C22, C23, C24 and a common-mode inductor L1, a TVS diode TVS1, a Buck voltage regulator circuit composed of a voltage regulator U2, a voltage regulator diode D2 and an inductor L2, a step-down filter circuit composed of capacitors C8, C9, C10, C11, a polarity capacitor C12 and inductors L3 and L4, and a TVS diode D3. One end of the fuse F1 is connected to the positive electrode of the 24V power supply through the power supply terminal CN1, the other end of the fuse F1 is connected to the positive electrode of the anti-reverse connection diode D1, the negative electrode of the anti-reverse connection diode D1 is respectively connected to the positive electrode of the polarity capacitor C1, one end of the capacitors C2, C3, C4 and pin 1 of the common-mode inductor L1, the pin 2 of the common-mode inductor L1 is respectively connected to the negative electrode of the polarity capacitor C1, the other end of the capacitors C2, C3, C4 and one end of the capacitors C21 and C22 and connected to the negative electrode of the 24V power supply through the power supply terminal CN1, the other end of the capacitor C21 is connected to the other end of C22 and connected to the PE ground through the power supply terminal CN1, and the pin 3 of the common-mode inductor L1 is respectively connected to the positive electrode of the TVS diode TVS1, one end of the capacitors C5, C6, C7 and the GROUND pin 3 of the regulator U2. , ON / OFF pin 5, TAB pin 6, the positive electrode of the Zener diode D2, one end of the capacitors C8, C9, C10, C11, the negative electrode of the polar capacitor C12, the inductor L4, the positive electrode of the TVS diode D3 and one end of the capacitors C23 and C24 are connected and grounded, the other ends of the capacitors C23 and C24 are connected and connected to the PE ground through the power supply terminal CN1, the pin 4 of the common mode inductor L1 is respectively connected to the negative electrode of the TVS diode TVS1, the other end of the capacitors C5, C6, C7 and the VIN pin 1 of the regulator U2, the OUT pin 2 of the regulator U2 is respectively connected to the negative electrode of the Zener diode D2, the inductor L2, the FB pin 4 of the regulator U2, the other end of the capacitors C8, C9, C10, C11, the positive electrode of the polar capacitor C12, the inductor L3 and the negative electrode of the TVS diode D3. As mentioned above, the DC24V voltage of the 24V power supply is protected against overcurrent and reverse connection through the fuse F1 and the anti-reverse connection diode D1, and then the surge spike before voltage reduction is absorbed by the common-mode and differential-mode filter circuits and the TVS diode TVS1, and then the 5V voltage is obtained through the Buck voltage regulator circuit, and finally the surge spike after voltage reduction is absorbed by the buck filter circuit and the TVS diode D3 to output the DC5V voltage power supply.

[0053] The 24V to 12V conversion circuit is a heating signal conversion circuit. The circuit structure of the 24V to 12V circuit includes a voltage regulator U5, a polar capacitor C13, and capacitors C14, C15, and C16. The VIN pin 2 of the voltage regulator U5 is respectively connected to the positive electrode of the polar capacitor C13 and one end of the capacitor C14, and is connected to the positive electrode of the 24V power supply through the fuse F1 and the anti-reverse diode D1 in the 24V to 5V conversion circuit. The GND pin 1 of the voltage regulator U5 is respectively connected to the negative electrode of the polar capacitor C13 and the other end of the capacitor C14 and connected to the negative electrode of the 24V power supply. The +VO pin 6 of the voltage regulator U5 is respectively connected to one end of the capacitors C15 and C16, and the -VO pin 7 of the voltage regulator U5 is respectively connected to the other end of the capacitors C15 and C16. As mentioned above, the DC24V voltage is isolated and stabilized by the 24V to 12V circuit to output the DC12V voltage power supply.

[0054] The circuit structure of the 5V to 3.3V conversion circuit includes a voltage regulator U4 and capacitors C17, C18, C19, and C20; the circuit structure of the 3.3V power supply indication circuit includes indicator lights LED1-1, LED1-2, and resistors R4 and R5. The VIN pin 3 of the voltage regulator U4 is connected to one end of the capacitors C17 and C18 respectively and connected to the positive electrode of the DC5V power supply, and the ADI (GND) pin 1 of the voltage regulator U4 is connected to the other end of the capacitors C17 and C18 respectively and connected to the negative electrode of the DC5V power supply. The VOUT (TAB) pin 2 of the voltage regulator U4 is connected to the ADI (GND) pin 1 of the voltage regulator U4 through the resistor R4 and LED1-1 in turn, and the TAB pin 4 of the voltage regulator U4 is connected to one end of the capacitors C19 and C20 respectively, and the other end of the capacitors C19 and C20 is connected and connected to the MCU controller U1 pin 31 in turn through the resistor R5 and LED1-2. As mentioned above, the DC5V voltage is linearly stabilized through the 5V to 3.3V conversion circuit to output a DC3.3V voltage power supply; the 3.3V power supply indication circuit is connected in parallel to the output end of the 5V to 3.3V conversion circuit to indicate the voltage output state of the 5V to 3.3V conversion circuit.

[0055] The circuit structure of the 5V voltage regulator circuit includes capacitors C115, C116, C117, C118, resistors R1, R2, R3, transistor Q13, voltage regulator U3 and test point T3. T3 is a test point on the board, just for the convenience of debugging and maintenance. Pin 1 of the voltage regulator U3 is connected to one end of resistors R2 and R3 respectively, the other end of resistor R2 is connected to the emitter of transistor Q13, one end of capacitors C117 and C118 and pin 1 of T3 respectively, the other end of resistor R3 is connected to the other end of capacitors C117 and C118, pin 3 of the voltage regulator U3 and one end of capacitors C115 and C116 respectively and connected to the negative electrode of the DC5V power supply, pin 2 of the voltage regulator U3 is connected to one end of resistor R1 and the base of transistor Q13 respectively, the collector of transistor Q13 is connected to the other end of resistor R1 and the other end of capacitors C115 and C116 respectively and connected to the positive electrode of the DC5V power supply. As mentioned above, the DC5V voltage is linearly stabilized by the 5V voltage regulator circuit to output the VREF reference voltage.

[0056] As mentioned above, this embodiment 1 converts the 24V voltage into 12V, 5V, 3.3V voltages and VREF reference voltage through the voltage conversion circuit and the voltage stabilization circuit in the power module, which can provide the power supply with the voltage required for the operation of each power module in the temperature control driver, as well as output the heating signal power supply, thereby effectively maintaining the normal operation of the temperature control driver.

[0057] like Figure 2 As shown, the MCU integrated chip includes the MCU controller U1 (see the figure for specific pin meanings), working clock circuit, RTC clock circuit, RTC backup power supply circuit, reset circuit, ADC power supply and reference circuit, program burning circuit, slave ID and communication baud rate selection circuit, the power input end of the MCU is connected to the DC3.3V power supply, and the MCU and its working clock and other peripheral circuits are all existing technologies, see the figure for details. Among them:

[0058] The circuit structure of the working clock circuit of the MCU includes a crystal oscillator Y1 and capacitors C107 and C108. Pin 37 of the MCU controller U1 is respectively connected to pin 1 of the crystal oscillator Y1 and one end of the capacitor C108, and the other end of the capacitor C108 is grounded. Pin 38 of the MCU controller U1 is respectively connected to pin 3 of the crystal oscillator Y1 and one end of the capacitor C107, and the other end of the capacitor C107 is connected to pin 2 of the crystal oscillator Y1 and grounded, which is used to provide timing data to the MCU controller U1.

[0059] The circuit structure of the RTC clock circuit of the MCU includes a crystal oscillator X1 and capacitors C112 and C113. The pin 31 of the MCU controller U1 is connected in series with one end of the crystal oscillator X1 and the capacitor C113 and grounded, and the pin 32 of the MCU controller U1 is connected in series with the other end of the crystal oscillator X1 and the capacitor C112 and grounded.

[0060] The circuit structure of the RTC backup power supply circuit of the MCU includes a battery B1, a bridge rectifier circuit D34 (two diodes are connected in reverse series) and a capacitor C109. The cathode common end of the two diodes of the bridge rectifier circuit D34 is connected to one end of the capacitor C109 and connected to the pin 30 of the MCU controller U1, the anodes of the two diodes are connected to the anode of the DC3.3V power supply and the anode of the battery B1, and the other end of the capacitor C109 is connected to the cathode of the battery B1 and the cathode of the DC3.3V power supply.

[0061] The circuit structure of the MCU reset circuit includes a resistor R195, a capacitor C101 and a switch SW4. Pin 64 of the MCU controller U1 is respectively connected to one end of the resistor R195, one end of the capacitor C101 and pin 1 of the switch SW4. The other end of the resistor R195 is connected to the positive electrode of the DC3.3V power supply. The other end of the capacitor C101 is connected to pin 2 of the switch SW4 and connected to the negative electrode of the DC3.3V power supply.

[0062] The circuit structure of the ADC power supply and reference circuit of the MCU includes capacitors C85, C86, C87, C88, C89, C90, C91, C92 and inductors L6, L7, L8. Pin 120 of the MCU controller U1 is respectively connected to one end of the capacitors C87, C88, C89 and one end of the inductor L8. The other end of the inductor L8 is respectively connected to one end of the capacitors C85 and C86 and connected to the positive electrode of the DC3.3V power supply. The MCU controller U1 Pin 121 is respectively connected to the other ends of capacitors C87, C88, C89, one ends of capacitors C90, C91, C92 and one end of inductor L7. The other end of inductor L7 is respectively connected to the other ends of capacitors C85 and C86 and connected to the negative pole of DC3.3V power supply. Pin 122 of MCU controller U1 is respectively connected to the other ends of capacitors C90, C91, C92 and one end of inductor L6. The other end of inductor L6 is connected to VREF reference voltage.

[0063] The circuit structure of the MCU program burning circuit includes J1 (connected to pin 64 (nRESET), pin 65 (ICE_DAT), and pin 66 (ICE_CLK) of U1) and diode D33. The circuit structure of the MCU slave ID and communication baud rate selection circuit includes SW2 and SW3 (selecting the communication rate and communication station address with the terminal device). SW2 and SW3 are connected to pins 71, 72, 73, 74 and pins 85, 86, 87, 88 of the MCU controller U1 respectively.

[0064] As mentioned above, the MCU in the temperature control driver of this Example 1 adopts existing technology, so that it can realize the execution of software programs, control of other modules, feedback processing of temperature information, data calculation, communication interface data processing and transmission, human-computer interaction and execution of instruction programs. Among them, the calculation processing of the MCU controller U1 adopts the existing PID algorithm calculation algorithm, so that the temperature control driver has independent PID temperature control, which can better meet the application occasions requiring multi-channel temperature control compared with single-channel temperature control. In this way, when multi-channel temperature control is required, not only the number of single-channel temperature controllers is reduced, but also the temperature controller is made smaller in size through integrated design, saving installation space.

[0065] As a preferred implementation, the temperature control module of this embodiment 1 includes 12 heating signal output circuits and heating output terminals CN3 and CN4, and the circuit structure of each heating signal output circuit is the same. In order to simplify the description, the utility model selects one of the heating signal output circuits for detailed description, and the circuit structure of the other 11 heating signal output circuits is shown in the figure and will not be repeated here.

[0066] like Figure 3-Figure 5 As shown, one of the heating signal output circuits includes an optocoupler isolation circuit. The circuit structure of the optocoupler isolation circuit includes a photocoupler U32 (a specific model example is TLP5701), an isolation resistor R155 and a fuse F20. The first input terminal pin 1 of the photocoupler U32 is connected to the pin 41 of the MCU controller U1 through the isolation resistor R155, the second input terminal pin 3 of the photocoupler U32 is connected to the pin 52 of the MCU controller U1 (the negative pole of the DC3.3V power supply), and the first load output terminal pin 6 and the second load output terminal pin 4 of the photocoupler U32 are respectively connected to the positive and negative poles of the DC12V power supply. Figure 4 , gives an example of a heating signal controlling an external heater circuit. The MCU controller U1 outputs a control signal that conducts the heating signal 12V voltage signal loop through the photocoupler U32, and then the optocoupler MOC3083S works, the optocoupler MOC3083S conducts the drive thyristor BTA41-800B, and the thyristor BTA41-800B conducts the live wire L and neutral wire N power supply loop of the heater, and the heater runs and heats. The first input ends of the remaining 11 optocoupler isolation circuits are connected to pins 42-51 and pin 69 of the MCU controller U1 respectively.

[0067] Based on the above example, in a preferred example, the heating signal output circuit also includes a heating output indication circuit, and the circuit structure of the heating output indication circuit includes an indicator LED3-1 and an indication resistor R168. The external voltage output pin 5 of the photocoupler U32 is connected to the positive electrode of the indicator LED3-1 through the fuse F20 and the indication resistor R168 in turn, and the negative electrode of the indicator LED3-1 is connected to the negative electrode of the DC12V power supply.

[0068] like Figure 6 As shown, the external voltage output terminal and the second load output terminal of the heating signal output circuit are connected to the heating output terminal CN3 or CN4, so that it can be connected to the power switch circuit of an external heating device (such as a heater, etc.) through the heating output terminal CN3 or CN4.

[0069] As mentioned above, the temperature control driver of this embodiment 1 can be connected to multiple heater power switch circuits through the heating output terminal. The number of heaters corresponds to the number of heating signal output circuits. The operator can use the temperature control driver to control the on or off of a single or multiple heater power switch circuits. The operation is convenient and quick, and the temperature control efficiency is improved.

[0070] Example 2

[0071] On the basis of Example 1, the heating signal output circuit of the PID temperature controller of Example 2 further includes 12 heater current detection circuits, and the circuit structure of each current detection circuit is the same, and the 12 current detection circuits are used in pairs with the 12 heating signal output circuits. In order to simplify the description, only one current detection circuit is selected in Example 2 for detailed description, and the circuit structures of the remaining 11 current detections are specifically shown in the figure, which will not be repeated here.

[0072] like Figure 7As shown, one of the current detection circuits includes a current detection signal processing circuit and a current transformer, and the current transformer can obtain the working current of the external heating device. The current detection signal processing circuit includes a rectifier and I / V conversion circuit and a follower, wherein the circuit structure of the rectifier and I / V conversion circuit includes a bridge rectifier circuit D9, a fuse F8, a resistor R119, a polarized capacitor C73, capacitors C49 and C50, and the circuit structure of the follower includes resistors R131, R132 and a follower U20; the output end of the current transformer is respectively connected to the first current signal input pin 1 and the second current signal input pin 3 of the bridge rectifier circuit D9 through the heating output terminal CN3, and the pin 2 of the bridge rectifier circuit D9 is connected to one end of the fuse F8, and the other end of the fuse F8 is respectively connected to one end of the resistor R119, the positive electrode of the polarized capacitor C73, One end of capacitors C49 and C50 is connected to one end of resistor R131, pin 4 of bridge rectifier circuit D9 is respectively connected to the other end of resistor R119, the negative electrode of polar capacitor C73 and the other end of capacitors C49 and C50 and connected to the negative electrode of DC5V power supply, the other end of resistor R131 is connected to +IN pin 3 of follower U20, -IN pin 4 of follower U20 is connected to one end of resistor R132, +VS pin 5 and -VS pin 2 of follower U20 are respectively connected to the positive electrode and negative electrode of DC5V power supply, and OUT pin 1 of follower U20 is connected to the other end of resistor R132 as the current signal output end and connected to pin 119 of MCU controller U1. The current signal output ends of the remaining 11 current detection circuits are respectively connected to pins 116-pin 118 and pins 13-pin 20 of MCU controller U1.

[0073] As mentioned above, the temperature control driver of the second embodiment uses the current detection signal processing circuit to rectify, I / V convert and smooth the current signal (CT1+, CT1-) of the current transformer through the rectification and I / V conversion circuit, and then obtains the voltage signal (I1) through the follower and sends it to the MCU part for sampling and conversion to obtain the current value of the external heating device. In the application, it can also detect in real time whether the heater is overcurrent or broken.

[0074] Example 3

[0075] On the basis of the above-mentioned embodiment 1 or embodiment 2, as a further preferred example, the PID temperature controller of this embodiment 3 also includes a temperature detection module, which is used to monitor the temperature of the temperature control object in real time and transmit its temperature information to the MCU. The temperature detection module includes 12 temperature detection circuits and a temperature output terminal CN5. The 12 temperature detection circuits are paired with 12 heating signal output circuits, and the circuit structure of each temperature detection circuit is the same, and one temperature detection circuit includes a temperature signal input circuit and a temperature sensor. In order to simplify the description, this embodiment 3 only selects one of the temperature detection circuits for detailed description, and the circuit structures of the other 11 temperature detections are specifically shown in the figure, which will not be repeated here.

[0076] like Figure 8-Figure 9 As shown, one of the temperature signal input circuits includes a bridge circuit and a differential amplifier circuit. The circuit structure of the bridge circuit includes resistors R21, R22, and R23, and the circuit structure of the differential amplifier circuit includes resistors R24, R25, R26, R27, R28 and a differential amplifier U8. One end of resistor R21 is connected to the output end of the temperature sensor through the temperature output terminal CN5 as the first temperature signal input end, the other end of resistor R21 is connected to one end of resistor R22 and connected to the VREF reference voltage, the other end of resistor R22 is respectively connected to one end of resistors R23 and R24, the other end of resistor R24 ​​is respectively connected to one end of resistor R26 and the negative input pin 4 of the differential amplifier U8, the other end of resistor R26 is respectively connected to one end of resistor R28 and the output pin 1 of the differential amplifier U8, the other end of resistor R28 is connected to pin 10 of the MCU controller U1 as the temperature signal output end, the positive input pin 3 of the differential amplifier U8 is respectively connected to one end of resistors R25 and R27, the other end of resistor R25 is connected to the output end of the temperature sensor through the temperature output terminal CN5 as the second temperature signal input end, the power pin 5 of the differential amplifier U8 is connected to the positive pole of the DC5V power supply, and the power pin 2 of the differential amplifier U8 is connected to the other end of resistors R27 and R23 and to the negative pole of the DC5V power supply. The remaining 11 temperature signal output terminals are respectively connected to pins 1 to 9 and pins 123 to 128 of the MCU controller U1. Specifically, the temperature sensor in this embodiment can be a three-wire PT temperature sensor with sensor wire resistance compensation.

[0077] As mentioned above, the temperature control driver of the present embodiment 3 can obtain the temperature numerical signal of the temperature control object through the temperature sensor in the temperature detection circuit, and then transmit the temperature numerical signal to the MCU through the temperature signal input circuit. In practical applications, the MCU can convert the temperature difference according to the temperature preset value and the temperature numerical value, and then control the temperature control module and the corresponding heating signal output circuit to output the heating signal according to the temperature difference, and adjust the temperature of the temperature control object until the temperature value monitored by the temperature sensor is within the range of the temperature preset value again. In addition, since a bridge plus a precision differential amplifier circuit is used in the temperature signal input circuit, the temperature detection accuracy can be higher and the temperature control can be more precise.

[0078] Example 4

[0079] On the basis of Example 3, as a further improved example, the PID temperature controller of Example 4 has an overcurrent protection function. Specifically, the temperature detection module of the PID temperature controller is provided with 12 overcurrent protection circuits, and the 12 overcurrent protection circuits are used in pairs with the 12 temperature detection circuits, and the circuit structure of each overcurrent protection circuit is the same. In order to simplify the description, only one overcurrent protection circuit is selected in Example 4 for detailed description, and the structures of the other 11 overcurrent protection circuits are shown in the figure, which will not be repeated here. It should be noted that the overcurrent protection circuit of Example 4 can refer to the existing technology for circuit design.

[0080] like Fig.10 As shown, the circuit structure of one of the overcurrent protection circuits includes a bridge voltage regulator circuit D21, a resistor R180, a field effect transistor Q1 and a fuse F32. Among them, the bridge voltage regulator circuit D21 is composed of 2 ordinary diodes and 2 TVS diodes, among which 1 ordinary diode and 1 TVS diode are connected in reverse series and then connected in parallel with the other group, one end (negative common end) of the bridge voltage regulator circuit D21 is respectively connected to one end of the resistor R180, and is connected to pin 80 of the MCU controller U1 as an overcurrent signal input end, the other end (the other negative common end) of the bridge voltage regulator circuit D21 is connected to the negative electrode of the DC5V power supply, the other end of the resistor R180 is connected to the gate of the field effect transistor Q1, the source of the field effect transistor Q1 is connected to the negative electrode of the DC24V power supply, the drain of the field effect transistor Q1 is connected to one end of the fuse F32, and the other end of the fuse F32 is connected to the temperature detection circuit through the temperature output terminal CN5 as an overcurrent signal output end, and the overcurrent signal input ends of the remaining 11 overcurrent protection circuits are respectively connected to pins 81-pin 83, pins 105-pin 111 and pin 115 of the MCU controller U1.

[0081] As described above, the PID temperature controller of the fourth embodiment checks the heater circuit and compares it with the set current. When overcurrent occurs, a signal is output from TSUB1 to drive the field effect transistor Q1 to turn on through the R180 resistor, thereby realizing an open-drain auxiliary output signal with overcurrent protection.

[0082] Example 5

[0083] On the basis of the above-mentioned embodiments 1, 2, 3 or 4, the PID temperature controller of this embodiment 5 has a communication function. Specifically, the PID temperature controller is provided with a communication module, which is used to realize the interactive connection between the PID temperature controller and the terminal control device. The communication module includes a communication terminal CN2, an RS485 communication transceiver circuit, a CAN communication transceiver circuit, a USB communication interface circuit, a terminal matching resistance selection circuit and a communication indication circuit. Among them:

[0084] like Figure 11-Figure 16 As shown, the circuit structure of the RS485 communication transceiver circuit includes a communication chip U6, resistors R6-R10, capacitors C25-C28, fuses F2-F3 and an ESD static and surge protection circuit D4. The VCC pin 1 of the communication chip U6 is respectively connected to one end of the capacitors C25 and C26 and connected to the positive electrode of the DC5V power supply. The GNDA pin 2 of the communication chip U6 is respectively connected to the other end of the capacitors C25 and C26 and connected to the negative electrode of the DC5V power supply. The RO pin 3, DE pin 5 and DI pin 6 of the communication chip U6 are respectively connected to one end of the resistors R6, R7 and R8. The other ends of the resistors R6, R7 and R8 are respectively connected to pins 58, 60 and 57 of the MCU controller U1. The RE pin 4 of the communication chip U6 is connected to the DE pin 5. The GNDA pin 7 of the communication chip U6 is connected to the GNDA pin 8 and connected to the negative electrode of the DC5V power supply. The GNDB pin 9 of the communication chip U6 is respectively connected to the capacitors C27 and C28. One end of the communication chip U6 is connected to the GNDB pin 15 of the communication chip U6 and is connected to the communication terminal CN2, the SEL pin 10 of the communication chip U6 is respectively connected to the VISO pin 16 of the communication chip U6, the other ends of the capacitors C27 and C28 and one end of the resistor R9, the A pin 12 of the communication chip U6 is respectively connected to the other end of the resistor R9, the pin 2 of the ESD static and surge protection circuit D4 and one end of the fuse F2, the other end of the fuse F2 is connected to the communication terminal CN2 as the first transmission end of RS485, the pin 13 of the communication chip U6 is respectively connected to one end of the resistor R10, the pin 1 of the ESD static and surge protection circuit D4 and one end of the fuse F3, the other end of the resistor R10 is connected to the GNDB pin 9 of the communication chip U6, the other end of the fuse F3 is connected to the communication terminal CN2 as the second transmission end of RS485, and the pin 3 of the ESD static and surge protection circuit D4 is connected to the GNDB pin 9 of the communication chip U6.

[0085] like Fig.12 As shown, the circuit structure of the CAN communication transceiver circuit includes a communication chip U7, capacitors C29-C32, resistors R15-R18, fuses F4-F5 and ESD static and surge protection circuit D5, the TXD pin 1, RXD pin 4, VIO pin 5 and STBY pin 8 of the communication chip U7 are respectively connected to one end of resistors R15, R16, R18 and R17, the other ends of resistors R15 and R16 are respectively connected to pins 62 and 63 of the MCU controller U1, the other end of resistor R18 is connected to the positive pole of the DC3.3V power supply, the other end of resistor R17 is connected to the negative pole of the 3.3V power supply, the VDD pin 3 of the communication chip U7 is respectively connected to one end of capacitors C29 and C30 and connected to the positive pole of the DC5V power supply, the capacitor The other ends of C29 and C30 and the VSS pin 2 of the communication chip U7 are connected to the negative electrode of the DC5V power supply. The CANL pin 6 of the communication chip U7 is respectively connected to the pin 2 of the ESD static and surge protection circuit D5, one end of the capacitor C32 and one end of the fuse F5. The other end of the fuse F5 is connected to the communication terminal CN2 as the first transmission end of CAN. The CANH pin 7 of the communication chip U7 is respectively connected to the pin 1 of the ESD static and surge protection circuit D5, one end of the capacitor C31 and one end of the fuse F4. The other end of the fuse F4 is connected to the communication terminal CN2 as the second transmission end of CAN. The other ends of the capacitors C32 and C31 and the pin 3 of the ESD static and surge protection circuit D5 are all connected to the negative electrode of the 3.3V power supply.

[0086] like Fig.14 As shown, the circuit structure of the USB communication interface circuit includes a communication chip USB1, a resistor R117-resistor R118, a capacitor C35-capacitor C36, a fuse F7 and a voltage-stabilizing diode D8. The VBUS pin 1 of the communication chip USB1 is respectively connected to one end of the capacitors C35 and C36, the fuse F7, the voltage-stabilizing diode D8 and the pin 91 of the MCU controller U1. The other ends of the capacitors C35 and C36 are connected to the negative electrode of the 3.3V power supply. The D- pin 2 and the D+ pin 3 of the communication chip USB1 are respectively connected to one end of the resistors R118 and R117. The other ends of the resistors R118 and R117 are respectively connected to the pins 92 and 94 of the MCU controller U1. The GND pin 4, the GND pin 5 and the GND pin 6 of the communication chip USB1 are connected to the negative electrode of the 3.3V power supply.

[0087] like Fig.16As shown, the circuit structure of the terminal matching resistor selection circuit includes a switch SW1, resistors R13 and R14, and two independent paths are respectively set between pins 1 and 4 and pins 2 and 3 of the switch SW1. Pins 1 and 4 of the switch SW1 are respectively connected to the A pin 12 of the communication chip U6 and one end of the resistor R13, and the other end of the resistor R13 is connected to the B pin 13 of the communication chip U6. Pins 2 and 3 of the switch SW1 are respectively connected to the CAHL pin 7 of the communication chip U7 and one end of the resistor R14, and the other end of the resistor R14 is connected to the CANH pin 6 of the communication chip U7. When the switch SW1 switches to the on state, the path can be selected to conduct the RS485 communication terminal matching resistor circuit or the CAN communication terminal matching resistor circuit loop. In this way, it can be selected whether to connect the terminal matching resistor circuit in different communication connection environments. SW1 is a dip switch, and the model example is DP-02RP; when the first position of the dip switch is turned to the ON position, the 1st and 4th pins of the dip switch SW1 are connected, and the RS485 communication terminal matching resistor circuit is selected; when the second position of the dip switch is turned to the ON position, the 2nd and 3rd pins of the dip switch SW1 are connected, and the CAN communication terminal matching resistor circuit loop is selected.

[0088] like Fig.15 As shown, the circuit structure of the communication indication circuit includes indicator lights LED2-1, LED2-2 and resistors R11-R12, one end of the resistors R11 and R12 are respectively connected to the positive pole of the DC5V power supply, the other end of the resistors R11 and R12 are respectively connected to the positive poles of the indicator lights LED2-1 and LED2-2, and the negative poles of the indicator lights LED2-1 and LED2-2 are respectively connected to the RO pin 3 of the communication chip U6 and the RXD pin 4 of the communication chip U7. The indicator lights LED2-1 and LED2-2 are respectively used for indicating the signal receiving status of the RS485 communication transceiver circuit and the CAN communication transceiver circuit.

[0089] As described above, the PID temperature controller of this embodiment 5 can be connected to the terminal control device through the communication module. In practical applications, after the PID temperature controller is connected to the terminal control device, the temperature value, heating status, etc. of each channel can be synchronously monitored through the terminal control device, and the control instructions sent by the terminal control device can be received, such as modifying the temperature preset value, stopping heating, etc. The PID temperature controller of this embodiment 5 has RS485, CAN and USB communication functions at the same time, which satisfies the control of terminal control devices with different communication interfaces and meets the needs of more industry application fields.

[0090] Example 6

[0091] On the basis of Examples 1, 2, 3, 4 or 5, the PID temperature controller of this Example 6 has an emergency control function. Specifically, the PID temperature controller is provided with an emergency control module, and the emergency control module includes 2 external event trigger circuits, and the circuit structure of each external event trigger circuit is consistent. In order to simplify the description, this Example 6 only describes one of the external event trigger circuits in detail, and the circuit structure of the other external event trigger circuit is shown in the figure.

[0092] like Fig.17 As shown, one of the external event trigger circuits includes a trigger switch, a resistor R19, a diode D6 and a photocoupler OP1, an input pin 1 of the photocoupler OP1 is respectively connected to the cathode of the diode D6 and one end of the resistor R19, the other end of the resistor R19 is connected to one end of the trigger switch through a communication terminal CN2, the other end of the trigger switch is respectively connected to the input pin 2 of the photocoupler OP1 and the anode of the diode D6 through the communication terminal CN2, an output pin 4 of the photocoupler OP1 is connected to the pin 56 of the MCU controller U1, and an output pin 3 of the photocoupler OP1 is grounded.

[0093] As described above, the PID temperature controller of the sixth embodiment can handle emergency situations through the emergency control module, such as shutting down the heating output.

[0094] Example 7

[0095] On the basis of the aforementioned embodiments 1, 2, 3, 4, 5 or 6, the PID temperature controller of the present embodiment 7 has a temperature data storage and recording function. Specifically, the PID temperature controller is provided with a data storage module, the data storage module includes a TF card interface circuit and a TF card, the circuit structure of the TF card interface circuit includes a resistor Rp1-a resistor Rp2, a capacitor C33-a capacitor C34, an inductor L5 and a fuse F6, the DAT2 pin 1, the DAT3 pin 2 and the CMD pin 3 of the TF card are respectively connected to the three output pins 1, 2 and 3 of the resistor Rp2, and the DAT0 pin of the TF card is connected to the DAT0 pin of the TF card. 7. DAT1 pin 8 and CD pin 9 are respectively connected to the three output pins 2, 3, and 4 of the resistor Rp1. The common pins 5, 6, 7, and 8 of the resistor Rp1 are connected to the common pins 5, 6, 7, and 8 of the resistor Rp2 and are connected to the positive electrode of the DC3.3V power supply. The VDD pin 4 of the TF card is respectively connected to one end of the capacitor C34 and one end of the inductor L5 through the fuse F6. The other end of the inductor L5 is connected to one end of the capacitor C33 and is connected to the positive electrode of the DC3.3V power supply. The other ends of the capacitors C34 and C33 and the VSS pin 6 of the TF card are all connected to the negative electrode of the DC3.3V power supply.

[0096] As mentioned above, the PID temperature controller of this embodiment 7 can record the temperature sampling value of the temperature detection module through the data storage module. In actual application, when the temperature value of the temperature control object exceeds the condition value, the data storage module can be triggered to record the current temperature value, which is convenient for subsequent operators to view.

[0097] As mentioned above, the utility model adopts 12-channel temperature control in terms of the number of channels, and each channel has an independent PID temperature control. Compared with single-channel temperature control, it can better meet the application occasions that require multi-channel temperature control, and has the advantages of small size and saving installation space. Temperature detection supports three-wire PT temperature sensor, with sensor wire resistance compensation, which will greatly reduce the additional error caused by wire resistance, and the temperature detection accuracy is high, and the temperature control is more accurate. Each channel has heater current detection, which can detect whether the heater is overcurrent or disconnected in real time. The PID temperature controller also has a temperature data storage and recording function, such as triggering the recording temperature when the temperature exceeds the range condition. It has an external event trigger function, and can use external trigger events to handle emergency situations, such as turning off the heating output. It has RS485, CAN, USB communication functions and switching conduction functions, which can meet the control of control devices with more communication interfaces. Therefore, the utility model improves the detection accuracy, is easy to operate, improves work efficiency, has better thermal insulation effect, and cannot store and record temperature data. It does not have heater current detection, and it is inconvenient to uniformly control and manage temperature.

[0098] It should be pointed out that the examples of the above-mentioned embodiments can be preferably combined with one or more of them according to actual needs, and multiple examples use a set of drawings to illustrate the combined technical features, which will not be described one by one here.

[0099] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0100] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A multi-channel PID temperature controller, comprising an MCU, a power module and a temperature control module, wherein the power module and the temperature control module are respectively connected to the MCU, and the power module is used to provide a working voltage for the operation of the PID temperature controller, characterized in that: The power supply module includes a heating signal conversion circuit to convert a heating signal power supply, and the temperature control module includes at least two heating signal output circuits, the input end of the heating signal output circuit is connected to the MCU, and the first load output end and the second load output end of the heating signal output circuit are respectively connected to the positive output end and the negative output end of the heating signal conversion circuit.

2. A multi-channel PID temperature controller according to claim 1, characterized in that: The power module includes a 24V power supply, a 24V to 5V conversion circuit, a 24V to 12V conversion circuit, a 5V to 3.3V conversion circuit and a 3.3V power indication circuit; the 24V to 5V conversion circuit is connected to the 24V power supply to convert the DC24V voltage into a DC5V voltage to output a 5V power supply; the heating signal conversion circuit is a 24V to 12V conversion circuit, which is connected to the 24V power supply to convert the DC24V voltage into a DC12V voltage to output a heating signal power supply; the 5V to 3.3V conversion circuit is connected to the 24V to 5V conversion circuit to convert the DC5V voltage into a DC3.3V voltage to output a 3.3V power supply; the 3.3V to 5V conversion circuit is connected to the 24V to 5V conversion circuit to convert the DC5V voltage into a DC3.3V voltage to output a 3.3V power supply; The positive and negative input terminals of the 3V power supply indication circuit are respectively connected to the positive and negative output terminals of the 5V to 3.3V conversion circuit, and are used to indicate the voltage output state of the 5V to 3.3V conversion circuit; wherein, the heating signal power supply is a 12V power supply, and the 12V power supply is output via the positive and negative output terminals of the voltage regulator U5, and the positive input terminal VIN of the voltage regulator U5 is respectively connected to one end of the capacitor C14 and the positive terminal of the polarity capacitor C13, and the negative terminal of the anti-reverse diode D1, and the positive pole of the anti-reverse diode D1 is connected to the positive pole of the 24V power supply through the fuse F1, and the negative input terminal GND of the voltage regulator U5 is respectively connected to the other end of the capacitor C14 and the negative terminal of the polarity capacitor C13, and the negative pole of the 24V power supply.

3. A multi-channel PID temperature controller according to claim 2, characterized in that: The circuit structure of each of the at least two heating signal output circuits is the same; one of the heating signal output circuits includes an optocoupler isolation circuit, which includes a photocoupler U and an isolation resistor, the first input pin 1 of the photocoupler U is connected to the MCU through the isolation resistor, the second input pin 3 of the photocoupler U is grounded, and the first load output pin 6 and the first load output pin 4 of the photocoupler U are respectively connected to the positive output terminal and the negative output terminal of the heating signal conversion circuit.

4. A multi-channel PID temperature controller according to claim 3, characterized in that: The heating signal output circuit also includes a heating output indication circuit, which includes an indicator light LED and an indication resistor. The external voltage output pin 5 of the photocoupler U is connected to the negative output terminal of the heating signal conversion circuit through the indicator light LED and the indication resistor in sequence.

5. A multi-channel PID temperature controller according to claim 2, characterized in that: It also includes at least two current detection circuits, which are used in pairs with the heating signal output circuit, and the circuit structure of each of the at least two current detection circuits is the same; one of the current detection circuits includes a current detection signal processing circuit and a current transformer, and the current detection signal processing circuit includes a rectification and I / V conversion circuit and a follower, the output end of the current transformer is connected to the input end of the follower through the current detection signal processing circuit, the output end of the follower is connected to the MCU, and the power pin of the follower is connected to a 5V power supply.

6. A multi-channel PID temperature controller according to claim 1, characterized in that: It also includes a temperature detection module, the temperature detection module includes at least two temperature detection circuits, the temperature detection circuit is used in pairs with the heating signal output circuit, and the circuit structure of each of the at least two temperature detection circuits is the same; wherein A temperature detection circuit includes a temperature signal input circuit and a temperature sensor. The temperature signal input circuit includes a bridge circuit and a differential amplifier circuit. The output end of the temperature sensor is connected to the MCU through the bridge circuit and the differential amplifier circuit in sequence.

7. A multi-channel PID temperature controller according to claim 2, characterized in that: It also includes a communication module, which includes an RS485 communication transceiver circuit, a CAN communication transceiver circuit and a USB communication interface circuit; the RS485 communication transceiver circuit includes a communication chip U6, a resistor R6-resistor R10, a capacitor C25-capacitor C28, a fuse F2-fuse F3 and an ESD static and surge protection circuit D4, the VCC pin 1 of the communication chip U6 is respectively connected to one end of the capacitor C25 and one end of the capacitor C26 and connected to the positive electrode of the 5V power supply, the GNDA pin 2 of the communication chip U6 is respectively connected to the other end of the capacitor C25 and the other end of the capacitor C26 and connected to the negative electrode of the 5V power supply, and the RO pin 3 of the communication chip U6 is connected to the positive electrode of the 5V power supply. , DE pin 5 and DI pin 6 are connected to one end of resistor R6, one end of resistor R7 and one end of resistor R8 respectively, the other end of resistor R6, the other end of resistor R7 and the other end of resistor R8 are connected to MCU respectively, RE pin 4 of the communication chip U6 is connected to DE pin 5, GNDA pin 7 of the communication chip U6 is connected to GNDA pin 8 and connected to the negative pole of 5V power supply, GNDB pin 9 of the communication chip U6 is connected to one end of capacitor C27, one end of capacitor C28 and GNDB pin 15 of the communication chip U6 respectively, SEL pin 10 of the communication chip U6 is connected to VISO pin 16 of the communication chip U6 and the other end of capacitor C27 respectively. The communication chip U6 is connected to one end of the resistor R9, the other end of the capacitor C28 is connected to one end of the resistor R9, the A pin 12 of the communication chip U6 is respectively connected to the other end of the resistor R9, the pin 2 of the ESD static and surge protection circuit D4 and one end of the fuse F2, the other end of the fuse F2 serves as the first transmission end of RS485, the pin 13 of the communication chip U6 is respectively connected to one end of the resistor R10, the pin 1 of the ESD static and surge protection circuit D4 and one end of the fuse F3, the other end of the resistor R10 is connected to the GNDB pin 9 of the communication chip U6, the other end of the fuse F3 serves as the second transmission end of RS485, the pin 3 of the ESD static and surge protection circuit D4 is connected to the communication chip U6, and the fuse F3 serves as the second transmission end of RS485. The CAN communication transceiver circuit includes a communication chip U7, a capacitor C29-capacitor C32, a resistor R15-resistor R18, a fuse F4-fuse F5 and an ESD static and surge protection circuit D5. The TXD pin 1, RXD pin 4, VIO pin 5 and STBY pin 8 of the communication chip U7 are respectively connected to one end of the resistor R15, one end of the resistor R16, one end of the resistor R18 and one end of the resistor R17. The other end of the resistor R15 and the other end of the resistor R16 are respectively connected to the MCU. The other end of the resistor R18 is connected to the positive electrode of the 3.3V power supply. The other end of the resistor R17 is connected to the 3.3V power supply.The negative electrode of the 3V power supply, the VDD pin 3 of the communication chip U7 is respectively connected to one end of the capacitor C29 and one end of the capacitor C30 and connected to the positive electrode of the 5V power supply, the other end of the capacitor C29, the other end of the capacitor C30 and the VSS pin 2 of the communication chip U7 are all connected to the negative electrode of the 5V power supply, the CANL pin 6 of the communication chip U7 is respectively connected to the pin 2 of the ESD static and surge protection circuit D5, one end of the capacitor C32 and one end of the fuse F5, the other end of the fuse F5 serves as the first transmission end of CAN, the CANH pin 7 of the communication chip U7 is respectively connected to the pin 1 of the ESD static and surge protection circuit D5, one end of the capacitor C31 and one end of the fuse F4, the other end of the fuse F4 serves as the second transmission end of CAN, the other end of the capacitor C32, the other end of the capacitor C31 and the ESD static and surge protection circuit D5 Pin 3 is connected to the negative pole of 3.3V power supply; the USB communication interface circuit includes communication chip USB1, resistor R117-resistor R118, capacitor C35-capacitor C36, fuse F7 and voltage regulator diode D8, the VBUS pin 1 of the communication chip USB1 is respectively connected to one end of capacitor C35, one end of capacitor C36, fuse F7, voltage regulator diode D8 and connected to MCU, the other end of capacitor C35 and the other end of capacitor C36 are connected to the negative pole of 3.3V power supply, the D- pin 2 and D+ pin 3 of the communication chip USB1 are respectively connected to one end of resistor R118 and one end of resistor R117, the other end of resistor R118 and the other end of resistor R117 are respectively connected to MCU, and the GND pin 4, GND pin 5 and GND pin 6 of the communication chip USB1 are all connected to the negative pole of 3.3V power supply. .

8. A multi-channel PID temperature controller according to claim 7, characterized in that: The communication module also includes a terminal matching resistor selection circuit and a communication indication circuit; the terminal matching resistor selection circuit includes a switch SW1 and resistors R13 and R14, and two independent paths are respectively set between pins 1, 4 and pins 2, 3 of the switch SW1, pin 4 of the switch SW1 is connected to one end of the resistor R13, and the other end of the resistor R13 and pin 1 of the switch SW1 are respectively connected to the B pin 13 and A pin 12 of the communication chip U6 of the RS485 communication transceiver circuit, and the pin 3 of the switch SW1 is connected to one end of the resistor R14, and the other end of the resistor R14 and pin 2 of the switch SW1 are respectively connected to the CANL pin 7 of the communication chip U7 of the CAN communication transceiver circuit. And CANH pin 6, so that when the switch SW1 is in the switching state, the RS485 communication terminal matching resistance circuit loop or the CAN communication terminal matching resistance circuit loop is turned on; the communication indication circuit includes an indicator light LED2-1, an indicator light LED2-2 and a resistor R11-resistor R12, one end of the resistor R11 and one end of the resistor R12 are respectively connected to the positive electrode of the 5V power supply, the other end of the resistor R11 and the other end of the resistor R12 are respectively connected to the positive electrode of the indicator light LED2-1 and the positive electrode of the indicator light LED2-2, the cathode of the indicator light LED2-1 and the cathode of the indicator light LED2-2 are respectively connected to the RO pin 3 of the communication chip U6 and the RXD pin 4 of the communication chip U7.

9. A multi-channel PID temperature controller according to claim 1, characterized in that: It also includes an emergency control module, which includes at least one external event trigger circuit, and the circuit structure of each external event trigger circuit is the same; one of the external event trigger circuits includes a trigger switch, a resistor R19, a diode D6 and a photoelectric coupler OP1, an input pin 1 of the photoelectric coupler OP1 is respectively connected to the cathode of the diode D6 and one end of the resistor R19, the other end of the resistor R19 is connected to one end of the trigger switch, the other end of the trigger switch is respectively connected to the input pin 2 of the photoelectric coupler OP1 and the anode of the diode D6, the output pin 4 of the photoelectric coupler OP1 is connected to the MCU, and the output pin 3 of the photoelectric coupler OP1 is grounded.

10. A multi-channel PID temperature controller according to claim 2, characterized in that: It also includes a data storage module, which includes a TF card interface circuit and a TF card. The TF card interface circuit includes resistors Rp1-Rp2, capacitors C33-C34, inductor L5 and fuse F6. The DAT2 pin 1, DAT3 pin 2 and CMD pin 3 of the TF card are respectively connected to the three output pins of the resistor Rp2, the DAT0 pin 7, DAT1 pin 8 and CD pin 9 of the TF card are respectively connected to the three output pins of the resistor Rp1, the common pin of the resistor Rp1 is connected to the common pin of the resistor Rp2 and connected to the positive electrode of the 3.3V power supply, the VDD pin 4 of the TF card is respectively connected to one end of the capacitor C34 and one end of the inductor L5 through the fuse F6, the other end of the inductor L5 is connected to one end of the capacitor C33 and connected to the positive electrode of the 3.3V power supply, and the other end of the capacitor C34, the other end of the capacitor C33 and the VSS pin 6 of the TF card are all connected to the negative electrode of the 3.3V power supply.

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