A refrigeration control device applied to reagent bin temperature control

Abstract

The present application relates to the technical field of temperature control, in particular to a refrigeration control device for reagent bin temperature control, comprising a controller and a refrigeration module; the refrigeration module comprises a signal detection input unit, a voltage following unit, a first comparison circuit unit, a second comparison circuit unit, a Schmitt trigger unit, a driving output unit, an optical coupling isolation unit and an output control unit; when the reagent bin is normally working, refrigeration related control is controlled by the controller; when the refrigeration switch is opened, the controller is powered off, and the refrigeration module circuit is self-adjusted to control refrigeration, so that the problem that the refrigeration module cannot realize temperature control under the condition that the MCU is powered off and the refrigeration module circuit is continuously powered is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of temperature control, in particular to a refrigeration control device for reagent bin temperature control. BACKGROUND

[0002] In vitro diagnostic equipment needs reagents to participate in the test process, and the equipment generally has a reagent bin for storing reagents needed in the instrument test process. The storage of reagents usually requires a specific temperature, and the conventional refrigeration temperature of reagents is 2-8℃. In the process of using the instrument, in order to ensure the stability and reliability of the test results, a controller MCU is usually used to cooperate with other drive circuits and modules to control the temperature of the reagent bin in a certain range, and refrigeration is performed on the reagent bin to maintain low temperature. Therefore, in the design of the general equipment, the instrument will be designed with two power switches, one switch is a refrigeration control switch, and the other is a general instrument power supply switch. In the normal use process, the general instrument power supply switch is turned on, but the refrigeration control switch is turned off. When the refrigeration control switch is turned on, all modules except the refrigeration module will be powered off. When the general instrument power supply switch is turned off, all modules of the instrument are powered off. Therefore, the doctor does not need to take the reagent out of the instrument and store it in the refrigerator after using the instrument. Only the refrigeration control switch needs to be turned on to achieve the power-off of all modules except the refrigeration module. The refrigeration function of the reagent bin of the instrument is normally operated to ensure low temperature.

[0003] The existing refrigeration control technology uses a temperature sensor to detect the temperature of the reagent bin, and transmits the detected changes to the controller MCU. The controller MCU controls the output through the internal algorithm to drive the corresponding circuit module to achieve the function of controlling the temperature of the reagent bin. When the instrument test is completed and the refrigeration switch is turned on, the control MCU still needs to be continuously powered. The MCU continuously works and monitors the temperature of the reagent bin at all times. Since the controller MCU has many functions, it is often connected to control other functions and modules of the equipment. When the refrigeration switch is turned on, all modules except the refrigeration module are in a power-off state, which can easily cause the MCU program to continuously identify errors during operation, and the program is easy to run away. And the controller MCU works continuously for a long time, which affects the service life. SUMMARY

[0004] The purpose of the present application is to provide a refrigeration control device for reagent bin temperature control, which aims to solve the problem that the refrigeration module cannot realize temperature control when the MCU is powered off and the refrigeration module circuit is continuously powered.

[0005] To achieve the above purpose, the present application provides a refrigeration control device for reagent bin temperature control, which comprises a controller and a refrigeration module.

[0006] The refrigeration module comprises a signal detection input unit, a voltage follower unit, a first comparison circuit unit, a second comparison circuit unit, a Schmitt trigger unit, a driving output unit, an optical coupling isolation unit and an output control unit, the signal detection input unit, the voltage follower unit, the first comparison circuit unit, the Schmitt trigger unit, the driving output unit, the optical coupling isolation unit and the output control unit are sequentially connected, one end of the second comparison circuit unit is connected with the voltage follower unit, the other side of the second comparison circuit unit is connected with the Schmitt trigger unit, one end of the controller is connected with the voltage follower unit, and the other end of the controller is connected with the driving output unit.

[0007] The signal detection input unit comprises a fourth resistor and a second thermistor, one end of the fourth resistor is connected with a power supply, the other end of the fourth resistor is connected with the voltage follower unit, one end of the second thermistor is grounded, and the other end of the second thermistor is connected with the other end of the fourth resistor.

[0008] The voltage follower unit comprises a second operational amplifier and a second capacitor, the non-inverting input end of the second operational amplifier is connected with the other end of the fourth resistor, the positive electrode of the second operational amplifier is connected with a power supply, the negative electrode of the second operational amplifier is grounded, one end of the second capacitor is connected with the positive electrode of the second operational amplifier, the other end of the second capacitor is grounded, the inverting input end of the second operational amplifier is connected with the output end of the second operational amplifier, and the controller is connected with the inverting input end of the second operational amplifier.

[0009] The first comparison circuit unit comprises a fifth resistor, a sixth resistor, a third operational amplifier, a third capacitor, a seventh resistor and an eighth resistor, one end of the fifth resistor is connected with the second capacitor, one end of the sixth resistor is grounded, the other end of the sixth resistor is connected with the other end of the fifth resistor, the non-inverting input end of the third operational amplifier is connected with the other end of the fifth resistor, the inverting input end of the third operational amplifier is connected with the output end of the second operational amplifier, one end of the third capacitor is connected with the positive electrode of the third operational amplifier, the other end of the third capacitor is grounded, the negative electrode of the third operational amplifier is grounded, one end of the eighth resistor is connected with the third capacitor, one end of the seventh resistor is connected with the output end of the third operational amplifier, and the other end of the seventh resistor is connected with the other end of the eighth resistor.

[0010] The second comparison circuit unit comprises an eleventh resistor, a twelfth resistor, a fifth operational amplifier, a fifth capacitor, a thirteenth resistor and a fourteenth resistor, one end of the twelfth resistor is connected with the positive pole of the fifth operational amplifier, one end of the eleventh resistor is grounded, the other end of the eleventh resistor is connected with the other end of the twelfth resistor, the noninverting input end of the fifth operational amplifier is connected with the other end of the eleventh resistor, one end of the fifth capacitor is connected with the positive pole of the fifth operational amplifier, the other end of the fifth capacitor is grounded, the inverting input end of the fifth operational amplifier is connected with the controller, the negative pole of the fifth operational amplifier is grounded, one end of the thirteenth resistor is connected with one end of the fifth capacitor, one end of the fourteenth resistor is connected with the output end of the fifth operational amplifier, the other end of the fourteenth resistor is connected with the other end of the thirteenth resistor.

[0011] The Schmidt trigger unit comprises a Schmidt trigger and a first capacitor, one end of the first capacitor is connected with the fifth pin of the Schmidt trigger, the other end of the first capacitor is grounded, the sixth pin of the Schmidt trigger is connected with the connection end of the seventh resistor and the eighth resistor.

[0012] The driving output unit comprises a fourth capacitor, a ninth resistor, a first triode and a gate driver, the controller is connected with the base of the first triode, the emitter of the first triode is grounded, one end of the fourth capacitor is connected with the fourth pin of the Schmidt trigger, the other end of the fourth capacitor is grounded, one end of the ninth resistor is connected with the fourth capacitor, the other end of the ninth resistor is connected with the collector of the first triode, the noninverting input end of the gate driver is connected with the connection end of the ninth resistor and the first triode, the third pin of the Schmidt trigger is connected with the inverting input end of the gate driver.

[0013] The optical coupling isolation unit comprises a tenth resistor and a first isolation optical coupling, the tenth resistor is connected with the output end of the gate driver, the positive pole of the first isolation optical coupling is connected with the other end of the tenth resistor, the negative pole and the emitter of the first isolation optical coupling are grounded.

[0014] The output control unit comprises a third resistor, a second triode, a first resistor, a field effect tube and a refrigeration unit, one end of the third resistor is connected with a power supply, the base of the second triode is connected with the other end of the third resistor, the collector of the first isolation optical coupler is connected with the connection end of the third resistor and the second triode, the emitter of the second triode is connected with the power supply, one end of the first resistor is connected with the collector of the second triode, the other end of the first resistor is grounded, the gate of the field effect tube is connected with the connection end of the first resistor and the second triode, the input end of the refrigeration unit is connected with the power supply, and the output end of the refrigeration unit is connected with the drain of the field effect tube.

[0015] The application discloses a refrigeration control device for reagent bin temperature control. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0017] Figure 1 It is a circuit block diagram of the refrigeration control device for reagent bin temperature control provided by the application.

[0018] Figure 2 It is a circuit diagram of the refrigeration control device for reagent bin temperature control provided by the application.

[0019] Figure 3 It is a circuit diagram of the signal detection input unit.

[0020] Figure 4 It is a circuit diagram of the voltage follower unit.

[0021] Figure 5 It is a circuit diagram of the first comparison circuit unit and the second comparison circuit unit.

[0022] Figure 6 It is a circuit diagram of the Schmitt trigger unit.

[0023] Figure 7 is a circuit diagram of a driving output unit.

[0024] Figure 8 is a circuit diagram of an optical coupling isolation unit.

[0025] Figure 9 is a circuit diagram of an output control unit.

[0026] Figure 10 is a working principle diagram of a refrigeration control device for reagent bin temperature control provided by the present application.

[0027] 1-controller, 2-refrigeration module, 3-signal detection input unit, 4-voltage follower unit, 5-first comparison circuit unit, 6-second comparison circuit unit, 7-Schmitt trigger unit, 8-driving output unit, 9-optical coupling isolation unit, 10-output control unit. DETAILED DESCRIPTION

[0028] Embodiments of the present application are described in detail below with reference to examples thereof illustrated in the accompanying drawings, in which like or similar elements or elements having the same or similar functions are denoted by the same or similar reference numerals throughout the drawings. The embodiments described below by reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as limiting the present application.

[0029] Referring to Figures 1 to 10 , the present application provides a refrigeration control device for reagent bin temperature control, comprising a controller 1 and a refrigeration module 2;

[0030] The refrigeration module 2 comprises a signal detection input unit 3, a voltage follower unit 4, a first comparison circuit unit 5, a second comparison circuit unit 6, a Schmitt trigger unit 7, a driving output unit 8, an optical coupling isolation unit 9, and an output control unit 10. The signal detection input unit 3, the voltage follower unit 4, the first comparison circuit unit 5, the Schmitt trigger unit 7, the driving output unit 8, the optical coupling isolation unit 9, and the output control unit 10 are connected in sequence. One end of the second comparison circuit unit 6 is connected to the voltage follower unit 4, and the other side of the second comparison circuit unit 6 is connected to the Schmitt trigger unit 7. One end of the controller 1 is connected to the voltage follower unit 4, and the other end of the controller 1 is connected to the driving output unit 8.

[0031] In the embodiment, when the reagent bin is working normally, the refrigeration-related control is controlled by the controller 1, when the refrigeration switch is opened, the controller 1 is powered off, and the refrigeration module 2 circuit is self-adjusted to control the refrigeration. Specifically, the signal detection input unit 3 detects the temperature of the reagent bin to obtain a temperature signal, the voltage follower unit 4 amplifies the temperature signal to obtain an amplified signal, and outputs the amplified signal to the first comparison circuit unit 5 and the second comparison circuit unit 6. The first comparison circuit unit 5 and the second comparison circuit unit 6 obtain the control temperature range of the reagent bin based on the amplified signal, and transmit the temperature range to the controller 1 and the Schmitt trigger unit 7. The Schmitt trigger unit 7 has two stable states, but unlike the general trigger, the Schmitt trigger unit 7 adopts a potential trigger mode, and its state is maintained by the input voltage. For input signals with different change directions of negative decreasing and positive increasing, the Schmitt trigger unit 7 has different threshold voltages.

[0032] When the controller 1 (control MCU) is working, the input voltage of the Schmitt trigger unit 7 is negatively decreasing, at this time the controller 1 triggers the drive output unit 8 to calculate a temperature adjustment value based on the temperature range, and transmits the temperature adjustment value to the output control unit 10, and the output control unit 10 adjusts the temperature of the reagent bin based on the temperature adjustment value.

[0033] When the controller 1 is powered off, the input voltage of the Schmitt trigger unit 7 is positively increasing, at this time the Schmitt trigger unit 7 triggers the drive output unit 8 to calculate a temperature adjustment value based on the temperature range, and transmits the temperature adjustment value to the output control unit 10, and the output control unit 10 adjusts the temperature of the reagent bin based on the temperature adjustment value.

[0034] The voltage of the units in the refrigeration module 2 except the refrigeration unit is low, in order to avoid the influence of the refrigeration unit on the work of the remaining units, the refrigeration unit is isolated from the remaining units in the refrigeration module 2 by the optical coupling isolation unit 9, and the stability of the refrigeration module 2 is increased. In the case that the controller 1 is powered off, the refrigeration module 2 can also work normally, solving the problem that in the existing refrigeration control technology, the control MCU will cause recognition error due to the fact that the remaining devices connected are in the powered-off state, thereby affecting the refrigeration effect of the refrigeration module 2 on the reagent bin, only when the refrigeration module 2 and the control MCU are powered on.

[0035] Further, the signal detection input unit 3 comprises a fourth resistor and a second thermistor, one end of the fourth resistor is connected with the power supply, the other end of the fourth resistor is connected with the voltage follower unit 4, one end of the second thermistor is grounded, the other end of the second thermistor is connected with the other end of the fourth resistor; the voltage follower unit 4 comprises a second operational amplifier and a second capacitor, the non-inverting input terminal of the second operational amplifier is connected with the other end of the fourth resistor, the positive electrode of the second operational amplifier is connected with the power supply, the negative electrode of the second operational amplifier is grounded, one end of the second capacitor is connected with the positive electrode of the second operational amplifier, the other end of the second capacitor is grounded, the inverting input terminal of the second operational amplifier is connected with the output terminal of the second operational amplifier, the controller is connected with the inverting input terminal of the second operational amplifier; the first comparison circuit unit 5 comprises a fifth resistor, a sixth resistor, a third operational amplifier, a third capacitor, a seventh resistor and an eighth resistor, one end of the fifth resistor is connected with the second capacitor, one end of the sixth resistor is grounded, the other end of the sixth resistor is connected with the other end of the fifth resistor, the non-inverting input terminal of the third operational amplifier is connected with the other end of the fifth resistor, the inverting input terminal of the third operational amplifier is connected with the output terminal of the second operational amplifier, one end of the third capacitor is connected with the positive electrode of the third operational amplifier, the other end of the third capacitor is grounded, the negative electrode of the third operational amplifier is grounded, one end of the eighth resistor is connected with the third capacitor, one end of the seventh resistor is connected with the output terminal of the third operational amplifier, the other end of the seventh resistor is connected with the other end of the eighth resistor; the second comparison circuit unit 6 comprises an eleventh resistor, a twelfth resistor, a fifth operational amplifier, a fifth capacitor, a thirteenth resistor and a fourteenth resistor, one end of the twelfth resistor is connected with the positive electrode of the fifth operational amplifier, one end of the eleventh resistor is grounded, the other end of the eleventh resistor is connected with the other end of the twelfth resistor, the non-inverting input terminal of the fifth operational amplifier is connected with the other end of the eleventh resistor, one end of the fifth capacitor is connected with the positive electrode of the fifth operational amplifier, the other end of the fifth capacitor is grounded, the inverting input terminal of the fifth operational amplifier is connected with the controller, the negative electrode of the fifth operational amplifier is grounded, one end of the thirteenth resistor is connected with one end of the fifth capacitor, one end of the fourteenth resistor is connected with the output terminal of the fifth operational amplifier, the other end of the fourteenth resistor is connected with the other end of the thirteenth resistor; the Schmitt trigger unit 7 comprises a Schmitt trigger and a first capacitor, one end of the first capacitor is connected with the fifth pin of the Schmitt trigger, the other end of the first capacitor is grounded, the sixth pin of the Schmitt trigger is connected with the connection end of the seventh resistor and the eighth resistor.The driving output unit 8 comprises a fourth capacitor, a ninth resistor, a first triode and a gate driver, the controller 1 is connected with the base of the first triode, the emitter of the first triode is grounded, one end of the fourth capacitor is connected with the fourth pin of the Schmitt trigger, the other end of the fourth capacitor is grounded, one end of the ninth resistor is connected with the fourth capacitor, the other end of the ninth resistor is connected with the collector of the first triode, the non-inverting input of the gate driver is connected with the connection end of the ninth resistor and the first triode, the third pin of the Schmitt trigger is connected with the inverting input of the gate driver; the optical coupling isolation unit 9 comprises a tenth resistor and a first isolation optical coupling, the tenth resistor is connected with the output of the gate driver, the other end of the tenth resistor is connected with the positive electrode of the first isolation optical coupling, the negative electrode and the emitter of the first isolation optical coupling are grounded; the output control unit 10 comprises a third resistor, a second triode, a first resistor, a field effect tube and a refrigeration unit, one end of the third resistor is connected with a power supply, the base of the second triode is connected with the other end of the third resistor, the collector of the first isolation optical coupling is connected with the connection end of the third resistor and the second triode, the emitter of the second triode is connected with a power supply, one end of the first resistor is connected with the collector of the second triode, the other end of the first resistor is grounded, the gate of the field effect tube is connected with the connection end of the first resistor and the second triode, the input of the refrigeration unit is connected with a power supply, and the output of the refrigeration unit is connected with the drain of the field effect tube.

[0036] The first pin of the Schmitt trigger is ground GND, the second pin is trigger TRIG, the third pin is output OUT, the fourth pin is reset RESET, the fifth pin is control voltage CONT, the sixth pin is threshold THRES, the eighth pin is discharge DISCH, and the ninth pin is power supply voltage Vcc.

[0037] In the embodiment, the second resistor (R2) is an NCT thermistor, which is used to detect the temperature of the reagent bin. The fourth resistor (R4) is connected to a 3V power supply (i.e. VREF_3V). The second resistor divides the voltage of the fourth resistor to obtain a first voltage V1: V1=VREF_3V*R2 / (R2+R4). Since the resistance of the second resistor changes with temperature, the first voltage V1 also changes with temperature. Therefore, the temperature change of V1 is the temperature change of the reagent bin. The second operational amplifier (U2) receives the voltage output V2 of V1 and outputs a voltage to the controller 1. The output impedance of the voltage amplifier is generally high, usually in the range of several kilohms to tens of kilohms. If the input impedance of the subsequent stage is small, a considerable part of the signal will be lost in the output resistance of the previous stage. At this time, the operational amplifier U2 is needed to buffer and play a role of connecting the previous stage and the subsequent stage. The second capacitor (C2) is used for energy storage and filtering to reduce the ripple of the power supply end of U2. The input voltage V3 of the third operational amplifier (U3) of the first comparison circuit unit 5 is VCC1*R6 / (R6+R5), where VCC1 is the input voltage of U2, R6 is the sixth resistor, and R5 is the fifth resistor. The input voltage V4 of the fifth operational amplifier (U5) of the second comparison circuit unit 6 is VCC1*R11 / (R11+R12), where R11 is the eleventh resistor and R12 is the twelfth resistor. V3 and V4 correspond to the upper and lower limits of the refrigeration temperature, respectively. By adjusting the values of V3 and V4, the refrigeration temperature range can be ensured. For example, the refrigeration temperature is set to T1-T2. By referring to the specification book of the thermistor, according to the corresponding relationship between the thermistor R2 and the temperature T, it is assumed that the value of R2 is R2' at T1, and the corresponding relationship between the temperature and the voltage at this time is V1'=VREF_3V*R2' / (R2'+R4). The value of R2 is R2" at T2, and the corresponding relationship between the temperature and the voltage at this time is V1"=VREF_3V*R2" / (R2"+R4). By adjusting the values of R5, R6, R11, and R12, V3=V1' and V4=V1" are obtained. Combined with the rear-end circuit, it can be ensured that the reagent bin temperature control is controlled within T1-T2. The two thresholds of the Schmidt trigger are V3 and V4, respectively. When the input voltage increases from low to high and reaches V4, the controller 1 is in a power-off state, and the output voltage Vo changes abruptly. When the input voltage decreases from high to low and reaches V3, the output voltage Vo changes abruptly. Therefore, the output voltage changes with a delay. It can be seen that the circuit is particularly suitable for circuits that require a certain delay to start, which can prevent frequent start switching and prolong the service life of the device.The controller 1 will collect the voltage V2, through the formula conversion of the detected temperature T, the first triode (Q1) is NPN triode, the second triode (Q2) is PNP triode, the Q1 is used to isolate the influence of the control port of the controller 1 after power off on the later stage circuit, the ninth resistor (R9) plays a role of pull-up, the gate driver (U4) is a single channel high speed low side gate driver, with high drive current, low propagation delay, negative voltage processing and under voltage lockout. U4 compares the values of input voltage V8 and V7, V8(R9) connects the same direction input end (IN+pin) of U4, V7(3) connects the reverse input end (IN-pipe foot) of U4.

[0038] When IN+ and IN- input is L, OUT output is L;

[0039] When IN+ input is L, IN- input is H, OUT output is L;

[0040] When IN+ input is H, IN- input is L, OUT output is H;

[0041] When IN+ input is H, IN- input is H, OUT output is L;

[0042] When IN+ is not connected, IN- input is H, OUT output is L;

[0043] When IN+ input is H, IN- is not connected, OUT output is L;

[0044] Wherein L is low level, H is high level, OUT output is the output end of the gate driver.

[0045] It can be seen that the output V9(OUT) is determined by the values of V8(IN+) and V7(IN-). In the entire circuit design, the design of all the previous circuits is to control the high and low changes of V9(OUT) to drive the start and stop of the refrigeration unit. When V9(OUT) is high, the refrigeration unit is powered on and refrigerates. When V9(OUT) is low, the refrigeration unit is not powered on and does not refrigerate. V8(IN+) is determined by the IO port C_CTR of the MCU. When the instrument is normally powered on, when the refrigeration unit is not less than the lowest value T1 of the set temperature, V7(IN-) outputs low L, so that the high and low changes of V8(IN+) can be controlled by the IO port C_CTR of the controller 1 to determine the refrigeration. When the controller 1 is powered off, V8(IN+) defaults to high H, and the change of the output V9(OUT) is controlled by V7(IN-). The change of V7(IN-) does not need to be controlled by the controller 1, and the change of V7(IN-) will change according to the change of the reagent bin temperature, so that when the refrigeration switch of the instrument is off, the hardware circuit can still realize the refrigeration function when the controller 1 is powered off. The function of the tenth resistor (R10) is to limit the current to prevent the output current from being too large and burning out the isolation optocoupler (U1). When V9 is high, U1 is turned on, and when V9 is low, U1 is not turned on. The working mode of the refrigeration unit (J1) of the output control module is powered on, and current flows through it to work normally. When powered off, the refrigeration unit stops working. The refrigeration unit is a semiconductor refrigeration unit. When the isolation optocoupler U1 is turned on, the PNP triode Q2 is turned on, and the field effect tube (MOS tube, Q3) is also turned on. For J1, the current flows from the input end (1 pin) of J1 to the refrigeration unit, and flows out from the output end (2 pin). Since Q3 is turned on at this time, the current is connected to the ground through Q3, forming a path, and the refrigeration unit works. Similarly, when the isolation optocoupler U1 is not turned on, the triode Q2 is not turned on, and Q3 is not turned on. At this time, the current flows from the 1 pin of J1 to the refrigeration unit and then flows out from the 3 pin, but since Q3 is not turned on, the current path to the ground is blocked, and a closed path cannot be formed. The voltage of the 1 pin and the 2 pin of J1 is consistent, there is no pressure difference, and no current flows through the refrigeration unit. Therefore, the refrigeration unit does not work at this time.

[0046] Assume that the reagent warehouse temperature needs to be controlled in the range of T1~T2, the working principle of the above refrigeration control device is as follows: VREF_3V we take 3V, R4 we take 22K, R2 we take BT series NCT thermistor BT103F3435B-30L50. According to the specification book of the manufacturer, when the temperature is T1~T2, the resistance value corresponding to R2 is about 16.6K~14.6K, according to the voltage division formula, V1=VREF_3V*R2 / (R2+R4), the voltage change of V1 is 1.29V~1.196V. Therefore, it is known that the voltage of V3 should be set to 1.19V, and the voltage of V4 is set to 1.29V. V3=VCC1*R6 / (R5+R6); V4=VCC1*R11 / (R11+R12). VCC1 we set to 5V, R5 take 15K, R6 take 4.7K, R11 take 1.5K, R12 take 4.32K. U3, U4 select low-cost operational amplifier TLV2379. R7, R8 are used for impedance matching and current limiting, here we take 100 ohms, R8, R13 are pull-up resistors, here we take 10K. The Schmitt trigger (U6) selects chip NE555.

[0047] 1. When the pin RESET (the fourth pin, i.e. pin 4) is LOW (low level), no matter whether the input of TRIGEER and THRESHOLD is high level or low level, the output OUTPUT is low level LOW,

[0048] 2. When RESET is high level, the level input by the TRIGEER pin is less than 1 / 3VCC, then no matter what level is input by the THRESHOLD pin, the OUTPUT output is high level HIGH

[0049] 3. When RESET is high level, the level input by the TRIGEER pin is greater than 1 / 3VCC, the level input by the THRESHOLD pin is greater than 2 / 3VCC, the OUTPUT output is high level HIGH

[0050] 4、When RESET is high level, the level of the input of the TRIGEER pin is greater than 1 / 3VCC, the level of the input of the THRESHOLD pin is less than 2 / 3VCC, the output of the OUTPUT is the output of the last state, if the last state of the OUTPUT is high level, the output of the OUTPUT is high level, if the last state of the OUTPUT is low level, the output of the OUTPUT is low level, when the voltage of the input pin 2 (TRIGGER) and the pin 6 (THRESHOLD) changes, the output of the pin 3 also changes. Q1 uses the transistor MMBT3904, U4 selects the single-channel gate driver model UCC27517DBVR, R9 is the pull-up resistor of 10K, when the controller 1 is powered off, Q1 is not conducting, so VCC1 is connected to the pin 3 (IN+) of U4 through the resistor R9 and is always high level, the output of U4 depends on the pin 4 (IN-), and the input of the pin 4 (IN-) depends on the output of the front-end U6. U1 is TLP521-1G, Q2 is MMBT3906, Q3 is CSD18542KCS, R3 and R1 are 10K. J1 represents the external refrigeration unit, and the refrigeration unit is a semiconductor refrigeration piece commonly used in the industry, which can be directly connected to the socket of J1.

[0051] Advantages:

[0052] 1. Reduce the power consumption of the whole machine after the instrument is powered off, and reduce the use cost of the instrument.

[0053] 2. The reagent refrigeration requires a certain fixed refrigeration temperature in the use process. However, there is no such strict requirement in storage. A certain range of temperature is required in storage, for example, the reagent storage temperature is set to 6℃ during instrument measurement. However, the storage temperature of the reagent after the instrument is powered off can be stored in the range of 2℃-8℃. The design can prolong the service life of the electronic components of the refrigeration part. Because the cold module is powered off after the instrument is powered off, the design can reduce the frequency of the refrigeration module 2 jumping around the set temperature. Because frequent switching will affect the performance and service life of the components, and the specific temperature values of T1 and T2 can be set by adjusting the values of the fifth resistor (R5), the sixth resistor (R6), the eleventh resistor (R11) and the twelfth resistor (R12) according to the needs of the doctors in the hospital.

[0054] 3. After the power-off, the refrigeration temperature control is dominated by hardware, and the controller 1 is not involved, especially in the design to save the cost of the instrument, in the instrument design, the controller 1 needs to control the refrigeration and monitor the state of other modules of the control instrument. But at this time, due to the power-off of other modules, the MCU may have program BUG, which affects the refrigeration. But at this time, due to the shutdown state of the display and other modules, no prompt can be given to inform the refrigeration failure. After the power-off, the refrigeration is controlled by the hardware, and the problem does not need to be worried about, which is more reliable and effective, and the MCU is completely powered off, preventing the MCU from working continuously for 24 hours.

[0055] The above only discloses a preferred embodiment of the refrigeration control device for temperature control of the reagent bin of the application, of course, cannot limit the scope of the rights of the application, and those skilled in the art can understand that all or part of the processes of the above-mentioned embodiments are implemented, and the equivalent changes made according to the claims of the application still belong to the scope covered by the application.

Claims

1. A refrigeration control device for temperature control in a reagent storage chamber, characterized in that, Includes controller and cooling module; The cooling module includes a signal detection input unit, a voltage follower unit, a first comparator circuit unit, a second comparator circuit unit, a Schmitt trigger unit, a drive output unit, an optocoupler isolation unit, and an output control unit. The signal detection input unit, the voltage follower unit, the first comparator circuit unit, the Schmitt trigger unit, the drive output unit, the optocoupler isolation unit, and the output control unit are connected in sequence. One end of the second comparator circuit unit is connected to the voltage follower unit, and the other end of the second comparator circuit unit is connected to the Schmitt trigger unit. One end of the controller is connected to the voltage follower unit, and the other end of the controller is connected to the drive output unit.

2. The refrigeration control device for reagent chamber temperature control as described in claim 1, characterized in that, The signal detection input unit includes a fourth resistor and a second thermistor. One end of the fourth resistor is connected to the power supply, and the other end of the fourth resistor is connected to the voltage follower unit. One end of the second thermistor is grounded, and the other end of the second thermistor is connected to the other end of the fourth resistor.

3. The refrigeration control device for reagent chamber temperature control as described in claim 2, characterized in that, The voltage follower unit includes a second operational amplifier and a second capacitor. The non-inverting input of the second operational amplifier is connected to the other end of the fourth resistor. The positive terminal of the second operational amplifier is connected to the power supply, and the negative terminal of the second operational amplifier is grounded. One end of the second capacitor is connected to the positive terminal of the second operational amplifier, and the other end of the second capacitor is grounded. The inverting input and output terminals of the second operational amplifier are connected. The controller is connected to the inverting input of the second operational amplifier.

4. The refrigeration control device for reagent chamber temperature control as described in claim 3, characterized in that, The first comparator circuit unit includes a fifth resistor, a sixth resistor, a third operational amplifier, a third capacitor, a seventh resistor, and an eighth resistor. One end of the fifth resistor is connected to the second capacitor. One end of the sixth resistor is grounded, and the other end of the sixth resistor is connected to the other end of the fifth resistor. The non-inverting input of the third operational amplifier is connected to the other end of the fifth resistor, and the inverting input of the third operational amplifier is connected to the output of the second operational amplifier. One end of the third capacitor is connected to the positive terminal of the third operational amplifier, and the other end of the third capacitor is grounded. The negative terminal of the third operational amplifier is grounded. One end of the eighth resistor is connected to the third capacitor. One end of the seventh resistor is connected to the output of the third operational amplifier, and the other end of the seventh resistor is connected to the other end of the eighth resistor.

5. The refrigeration control device for reagent chamber temperature control as described in claim 4, characterized in that, The second comparator circuit unit includes an eleventh resistor, a twelfth resistor, a fifth operational amplifier, a fifth capacitor, a thirteenth resistor, and a fourteenth resistor. One end of the twelfth resistor is connected to the positive terminal of the fifth operational amplifier. One end of the eleventh resistor is grounded, and the other end of the eleventh resistor is connected to the other end of the twelfth resistor. The non-inverting input terminal of the fifth operational amplifier is connected to the other end of the eleventh resistor. One end of the fifth capacitor is connected to the positive terminal of the fifth operational amplifier, and the other end of the fifth capacitor is grounded. The inverting input terminal of the fifth operational amplifier is connected to the controller, and the negative terminal of the fifth operational amplifier is grounded. One end of the thirteenth resistor is connected to one end of the fifth capacitor. One end of the fourteenth resistor is connected to the output terminal of the fifth operational amplifier, and the other end of the fourteenth resistor is connected to the other end of the thirteenth resistor.

6. The refrigeration control device for reagent chamber temperature control as described in claim 5, characterized in that, The Schmitt trigger unit includes a Schmitt trigger and a first capacitor. One end of the first capacitor is connected to the fifth pin of the Schmitt trigger, and the other end of the first capacitor is grounded. The sixth pin of the Schmitt trigger is connected to the connection terminal of the seventh resistor and the eighth resistor.

7. The refrigeration control device for reagent chamber temperature control as described in claim 6, characterized in that, The drive output unit includes a fourth capacitor, a ninth resistor, a first transistor, and a gate driver. The controller is connected to the base of the first transistor, and the emitter of the first transistor is grounded. One end of the fourth capacitor is connected to the fourth pin of the Schmitt trigger, and the other end of the fourth capacitor is grounded. One end of the ninth resistor is connected to the fourth capacitor, and the other end of the ninth resistor is connected to the collector of the first transistor. The non-inverting input of the gate driver is connected to the junction of the ninth resistor and the first transistor. The third pin of the Schmitt trigger is connected to the inverting input of the gate driver.

8. The refrigeration control device for reagent chamber temperature control as described in claim 7, characterized in that, The optocoupler isolation unit includes a tenth resistor and a first isolation optocoupler. The tenth resistor is connected to the output terminal of the gate driver. The positive terminal of the first isolation optocoupler is connected to the other end of the tenth resistor. The negative terminal and emitter of the first isolation optocoupler are grounded.

9. The refrigeration control device for reagent chamber temperature control as described in claim 8, characterized in that, The output control unit includes a third resistor, a second transistor, a first resistor, a field-effect transistor (FET), and a cooling unit. One end of the third resistor is connected to a power supply. The base of the second transistor is connected to the other end of the third resistor. The collector of the first isolation optocoupler is connected to the connection point of the third resistor and the second transistor. The emitter of the second transistor is connected to a power supply. One end of the first resistor is connected to the collector of the second transistor, and the other end of the first resistor is grounded. The gate of the FET is connected to the connection point of the first resistor and the second transistor. The source of the FET is grounded. The input of the cooling unit is connected to a power supply, and the output of the cooling unit is connected to the drain of the FET.

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