CN115790777A - Liquid level detection device - Google Patents
Liquid level detection device Download PDFInfo
- Publication number
- CN115790777A CN115790777A CN202310010570.8A CN202310010570A CN115790777A CN 115790777 A CN115790777 A CN 115790777A CN 202310010570 A CN202310010570 A CN 202310010570A CN 115790777 A CN115790777 A CN 115790777A
- Authority
- CN
- China
- Prior art keywords
- circuit
- capacitor
- power supply
- pin
- resistor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Abstract
The invention provides a liquid level detection device, which belongs to the field of full-automatic magnetic particle chemiluminescence immunoassay and comprises a signal generation circuit, a sampling needle static capacitance matching circuit, an oscillation circuit, a logic operation circuit and a rear-end processing circuit, wherein the signal generation circuit is respectively and electrically connected with the sampling needle static capacitance matching circuit and the oscillation circuit; according to the invention, the time base chip and the Schmidt inverter are used for building the signal generating circuit to improve the stability of the signal, the phase difference of two paths of square signals is stably input into the logic operation circuit for operation when the square signals contact the liquid level by using the characteristics of the logic device, the defect that the analog signals are easy to interfere is avoided, the high sensitivity is ensured, the anti-interference capability and stability are greatly improved, the circuit complexity is simplified, and the cost is reduced.
Description
Technical Field
The invention relates to the field of full-automatic magnetic particle chemiluminescence immunoassay, in particular to a liquid level detection device.
Background
In the field of full-automatic magnetic particle chemiluminescence immunoassay, a liquid level detection device is generally used for sensing the contact of a sample adding needle with a liquid level, so that accurate sample adding operation is carried out, and the fact that whether the liquid level detection device can effectively detect the liquid level without interference is particularly important; on the premise of meeting the requirement of sample adding quantity, the contact area between the sample adding needle and liquid is minimized as much as possible, so that the waste of reagents or samples can be reduced, and the cross contamination can be avoided, thereby having great requirements on the anti-interference capability and the reliability of the liquid level detection device.
The existing liquid level detection method is characterized in that a capacitance is converted into a voltage, the voltage is subjected to multiple steps of processing such as operational amplification, A/D conversion and the like, and then the quantization process of the capacitance value is completed.
Disclosure of Invention
The invention aims to provide a liquid level detection device, which improves the anti-interference capability and reliability of full-automatic magnetic particle chemiluminescence immunoassay in the liquid level detection process and greatly reduces the circuit cost.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a liquid level detection device comprises a signal generation circuit, a sampling needle static capacitance matching circuit, an oscillation circuit, a logic operation circuit and a rear-end processing circuit, wherein the signal generation circuit is electrically connected with the sampling needle static capacitance matching circuit and the oscillation circuit respectively, the sampling needle static capacitance matching circuit and the oscillation circuit are electrically connected with the logic operation circuit respectively, the logic operation circuit is electrically connected with the rear-end processing circuit, and the oscillation circuit is electrically connected with a sampling needle.
As a further improvement of the above technical solution:
the signal generating circuit comprises a time-base chip U1, a Schmidt phase inverter U3, a capacitor C1 and a resistor R13, wherein a pin 4 of the time-base chip U1 is grounded, and a pin 5 of the time-base chip U1 is connected with one input pin 6 of the Schmidt phase inverter U3; the resistor R13 is a configuration resistor of the output frequency of the time-base chip U1, one end of the resistor R is connected with the pin 3 of the time-base chip U1, and the other end of the resistor R is connected with a GND power supply network; the capacitor C1 is a power supply decoupling capacitor of the time-base chip U1, one end of the capacitor C is connected with a pin 1 of the time-base chip U1 and a 5V power supply network, and the other end of the capacitor C is connected with a pin 2 of the time-base chip U1 and a GND power supply network.
The model of the time base chip U1 is LTC1799CS5# PBF, and the model of the Schmitt inverter U3 is SN74LVC3G14DCUR.
The signal generating circuit further comprises a capacitor C3, a resistor R1 and a resistor R2, and a pin 4 of the Schmidt inverter U3 is connected with a GND power supply network; one path of carrier signal output pin 2 of the Schmidt phase inverter U3 is respectively connected with one ends of a resistor R1 and a resistor R2, the other end of the resistor R1 is connected with an oscillating circuit, and the other end of the resistor R2 is connected with a static capacitance matching circuit of a sampling needle.
And the capacitor C3 is a power supply decoupling capacitor of the Schmidt inverter U3, one end of the capacitor C is connected with a GND power supply network, and the other end of the capacitor C is connected with a power supply pin 8 and a 5V power supply network of the Schmidt inverter U3.
The signal generating circuit further comprises a diode V1 and a diode V2, a common anode pin of the diode V1 is connected with a GND power supply network, a common cathode pin 3 of the diode V2 is connected with a 5V power supply network, and two cathode pins 1 and 2 of the diode V1 are respectively connected with two anode pins 1 and 2 of the diode V2 to form a 0V-5V clamping circuit.
The oscillation circuit comprises a resistor R14 and an inductor L4, one end of the resistor R14 is connected with one input pin 1 of the Schmidt inverter U3, and the other end of the resistor R14 is connected with one end of the inductor L4; the other end of the inductor L4 is connected with the inner wall of the sampling needle J0.
The static capacitance matching circuit of the sampling needle comprises a capacitor C2, one end of the capacitor C2 is connected with a GND power supply network, and the other end of the capacitor C2 is connected with one signal input pin 3 of a Schmidt phase inverter U3.
The logic operation circuit comprises an exclusive-OR gate U2 and a capacitor C4, wherein the capacitor C4 is a power supply decoupling capacitor of the exclusive-OR gate U2, one end of the capacitor C4 is connected with a GND power supply network, and the other end of the capacitor C4 is connected with a power supply pin 5 and a 5V power supply network of the exclusive-OR gate U2; one path of oscillation circuit signal output pin 7 of the Schmidt inverter U3 is connected with the signal input pin 1 of the exclusive-OR gate U2; a signal output pin 5 of a static capacitance matching circuit of a sampling needle of the Schmidt inverter U3 is connected with a signal input pin 2 of the exclusive-OR gate U2; a pin 3 of the exclusive-OR gate U2 is connected with a GND power supply network; the output pin 4 of the exclusive-or gate is connected with a back-end processing circuit.
The type of the exclusive-OR gate U2 is TC7S86F, and the back-end processing circuit comprises an MCU of which the type is STM32F103CBT 6.
By adopting the technical scheme, the invention has the following advantages: the invention is different from the existing liquid level detection method for converting capacitance into voltage, does not need to carry out signal frequency division, frequency conversion, amplification, A/D conversion, comparison circuit construction and other complex steps on signals, builds a signal generation circuit by using a time base chip and a Schmitt inverter to improve the stability of the signals, completes signal filtering and shaping by using an oscillation circuit signal, the Schmitt inverter, a sampling needle static capacitance matching circuit and the Schmitt inverter, stably inputs phase difference of two paths of square signals when contacting the liquid level into a logic operation circuit by using the characteristics of a logic device to operate, avoids the defect that analog signals are easy to be interfered, greatly improves the anti-interference capability and stability while ensuring high sensitivity, simplifies the circuit complexity and reduces the cost.
The invention is further described with reference to the following figures and detailed description.
Drawings
FIG. 1 is a block diagram of a liquid level detecting apparatus according to an embodiment of the present invention;
FIG. 2 is a schematic circuit diagram of a liquid level detecting device according to an embodiment of the present invention.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to examples, in which specific conditions are not specified, and which are performed according to conventional conditions or conditions recommended by manufacturers. The reagents or instruments used are not indicated by manufacturers, and are all conventional products available on the market.
The embodiments described are only a part of the embodiments of the present invention, and not all embodiments, and all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without any inventive work belong to the protection scope of the present invention.
Example (b):
as shown in fig. 1, a liquid level detecting device includes a signal generating circuit, a sampling needle static capacitance matching circuit, an oscillating circuit, a logic operation circuit and a back-end processing circuit, wherein the signal generating circuit is electrically connected to the sampling needle static capacitance matching circuit and the oscillating circuit, the sampling needle static capacitance matching circuit and the oscillating circuit are electrically connected to the logic operation circuit, the logic operation circuit is electrically connected to the back-end processing circuit, and the oscillating circuit is electrically connected to the sampling needle.
The static state of the sample application needle refers to the state when the sample application needle is not in contact with the liquid surface, including the static state and the moving state but not in contact with the liquid surface.
As shown in fig. 2, the signal generating circuit includes a time base chip U1, a schmitt inverter U3, a capacitor C1, and a resistor R13, where the model of the time base chip U1 is LTC1799CS5# PBF, the model of the schmitt inverter U3 is SN74LVC3G14DCUR, a pin 4 of the time base chip U1 is grounded, a frequency division coefficient N =1 is selected, and a square wave signal with a fixed frequency can be generated by configuring the value of the resistor R13, according to the formula:
the value of the configuration resistor R13 can generate a square wave signal of about 2.1MHz, and the signal is connected with one input pin 6 of the Schmitt phase inverter U3 through a pin 5 of the time-base chip U1; the resistor R13 is a configuration resistor of the output frequency of the time-base chip U1, one end of the resistor R is connected with the pin 3 of the time-base chip U1, and the other end of the resistor R is connected with a GND power supply network; the capacitor C1 is a power supply decoupling capacitor of the time-base chip U1, one end of the capacitor C is connected with a pin 1 of the time-base chip U1 and a 5V power supply network, and the other end of the capacitor C is connected with a pin 2 of the time-base chip U1 and a GND power supply network.
The signal generating circuit further comprises a capacitor C3, a resistor R1 and a resistor R2, the Schmidt phase inverter U3 filters and enhances an input signal and then outputs a square wave signal with an amplitude of 5V and more ideal rising/falling edges, and a pin 4 of the square wave signal is connected with a GND power supply network; one path of carrier signal output pin 2 of the Schmidt inverter U3 is respectively connected with one ends of a resistor R1 and a resistor R2, the other end of the resistor R1 is connected with an oscillating circuit, and the other end of the resistor R2 is connected with a sampling needle static capacitance matching circuit; and the capacitor C3 is a power supply decoupling capacitor of the Schmidt inverter U3, one end of the capacitor C is connected with a GND power supply network, and the other end of the capacitor C is connected with a power supply pin 8 and a 5V power supply network of the Schmidt inverter U3.
The signal generating circuit further comprises a diode V1 and a diode V2, a common anode pin of the diode V1 is connected with a GND power supply network, a common cathode pin 3 of the diode V2 is connected with a 5V power supply network, two cathode pins 1 and 2 of the diode V1 are respectively connected with two anode pins 1 and 2 of the diode V2 to form a 0V-5V clamping circuit, and the amplitude of a signal waveform input to a pin signal loop at the input end of the Schmidt inverter U3 by the oscillating circuit and the sampling needle static capacitance matching circuit is clamped between 0V and 5V in the signal generating circuit, so that the stability of the circuit is improved.
The oscillating circuit comprises a resistor R14 and an inductor L4, one end of the resistor R14 is connected with one input pin 1 of the Schmidt inverter U3, and the other end of the resistor R14 is connected with one end of the inductor L4; the other end of the inductor L4 is connected with the inner wall of the sampling needle J0, a capacitance effect is formed between the sampling needle J0 and the ground, and the capacitance effect is formed according to a formula
The capacitance value generated when the liquid is contacted with the liquid is larger than the capacitance value of the sampling needle in a static state, and the waveform influence of the capacitance effect between the sampling needle and the ground on the RLC oscillation circuit is different.
The sampling needle static capacitance matching circuit comprises a capacitor C2, one end of the capacitor C2 is connected with a GND power supply network, the other end of the capacitor C is connected with one signal input pin 3 of a Schmidt phase inverter U3, and the capacitor C is used for matching the waveform of the oscillating circuit when the sampling needle is static.
The logic operation circuit comprises an exclusive-OR gate U2 and a capacitor C4, wherein the model of the exclusive-OR gate U2 is TC7S86F, the capacitor C4 is a power supply decoupling capacitor of the exclusive-OR gate U2, one end of the capacitor C4 is connected with a GND power supply network, and the other end of the capacitor C4 is connected with a power supply pin 5 and a 5V power supply network of the exclusive-OR gate U2; one path of oscillation circuit signal output pin 7 of the Schmidt inverter U3 is connected with the signal input pin 1 of the exclusive-OR gate U2; a signal output pin 5 of a static capacitance matching circuit of a sampling needle of the Schmidt phase inverter U3 is connected with a signal input pin 2 of the exclusive-OR gate U2; a pin 3 of the exclusive-OR gate U2 is connected with a GND power supply network; and an output pin 4 of the exclusive-OR gate outputs the phase difference of signal waveforms of the oscillating circuit and the static capacitance matching circuit of the sampling needle, and square wave signals are input into a rear-end processing circuit.
The rear-end processing circuit comprises an MCU (micro control unit) with the model number of STM32F103CBT6, the width of a square wave transmitted by the logic operation circuit is calculated by configuring an internal input capture channel, when the MCU detects a first square wave pulse (from a rising edge to a falling edge), whether the high level time of the next continuous 3 square wave pulses is more than 40ns or not is judged, if yes, the MCU judges that the sampling needle is in contact with the liquid level, and meanwhile, a motion stop signal is sent to the motion module.
The working principle is as follows: the signal generating circuit generates a signal with fixed frequency, the signal is shaped and filtered by the Schmidt inverter and then is respectively input into the oscillating circuit and the sampling needle static capacitance matching circuit, a capacitance effect exists between the inner wall of the sampling needle and a casing (ground), the capacitance, the inductance and the resistance form an RLC oscillating circuit, the signal waveform change of the oscillating circuit caused by the sampling needle static capacitance is offset and matched by the sampling needle static capacitance matching circuit, thus after the signal enters the Schmidt inverter, the signal of the sampling needle static capacitance and the signal of the sampling needle static capacitance do not have phase offset, and the signal with the pulse width approximate to 0 is output in the logic operation circuit; when the sampling needle contacts the liquid surface, the capacitance can generate pF level increase change, the change affects the rising and falling time of a signal waveform input to the oscillating circuit, the change is converted into phase deviation of the signal waveform by utilizing the characteristics of threshold judgment and waveform holding of the Schmidt inverter, when the sampling needle contacts the liquid surface, the signal of the static capacitance matching circuit of the sampling needle generates a phase difference of about 50ns after passing through the Schmidt inverter, the phase difference outputs a square wave signal with a pulse width of about 50ns after passing through an XOR gate in the logic operation circuit, and the pulse width detection is carried out by the rear end circuit to judge whether the sampling needle contacts the liquid surface.
Finally, it should be noted that: the above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and the embodiments are examples, wherein the details that are not described are all the common general knowledge of those skilled in the art, and the technical solutions described in the foregoing embodiments can be modified or some technical features can be equivalently replaced by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A liquid level detection device characterized by: the device comprises a signal generating circuit, a sampling needle static capacitance matching circuit, an oscillating circuit, a logic operation circuit and a rear-end processing circuit, wherein the signal generating circuit is respectively and electrically connected with the sampling needle static capacitance matching circuit and the oscillating circuit, the sampling needle static capacitance matching circuit and the oscillating circuit are respectively and electrically connected with the logic operation circuit, the logic operation circuit is electrically connected with the rear-end processing circuit, and the oscillating circuit is electrically connected with a sampling needle.
2. A liquid level detection device as claimed in claim 1, wherein: the signal generating circuit comprises a time-base chip U1, a Schmidt phase inverter U3, a capacitor C1 and a resistor R13, wherein a pin 4 of the time-base chip U1 is grounded, and a pin 5 of the time-base chip U1 is connected with one input pin 6 of the Schmidt phase inverter U3; the resistor R13 is a configuration resistor of the output frequency of the time-base chip U1, one end of the resistor R is connected with the pin 3 of the time-base chip U1, and the other end of the resistor R is connected with a GND power supply network; the capacitor C1 is a power supply decoupling capacitor of the time-base chip U1, one end of the capacitor C is connected with a pin 1 of the time-base chip U1 and a 5V power supply network, and the other end of the capacitor C is connected with a pin 2 of the time-base chip U1 and a GND power supply network.
3. A liquid level detection device as claimed in claim 2, wherein: the model of the time base chip U1 is LTC1799CS5# PBF, and the model of the Schmitt inverter U3 is SN74LVC3G14DCUR.
4. A liquid level detection device as claimed in claim 3, wherein: the signal generating circuit further comprises a capacitor C3, a resistor R1 and a resistor R2, and a pin 4 of the Schmidt inverter U3 is connected with a GND power supply network; one path of carrier signal output pin 2 of the Schmidt inverter U3 is respectively connected with one ends of a resistor R1 and a resistor R2, the other end of the resistor R1 is connected with an oscillating circuit, and the other end of the resistor R2 is connected with a sampling needle static capacitance matching circuit.
5. A liquid level detection device as claimed in claim 4, wherein: and the capacitor C3 is a power supply decoupling capacitor of the Schmidt inverter U3, one end of the capacitor C is connected with a GND power supply network, and the other end of the capacitor C is connected with a power supply pin 8 and a 5V power supply network of the Schmidt inverter U3.
6. A liquid level detection device as claimed in claim 5, wherein: the signal generating circuit further comprises a diode V1 and a diode V2, a common anode pin of the diode V1 is connected with a GND power supply network, a common cathode pin 3 of the diode V2 is connected with a 5V power supply network, and two cathode pins 1 and 2 of the diode V1 are respectively connected with two anode pins 1 and 2 of the diode V2 to form a 0V-5V clamping circuit.
7. A liquid level detection device as claimed in claim 6, wherein: the oscillation circuit comprises a resistor R14 and an inductor L4, one end of the resistor R14 is connected with one input pin 1 of the Schmidt inverter U3, and the other end of the resistor R14 is connected with one end of the inductor L4; the other end of the inductor L4 is connected with the inner wall of the sampling needle J0.
8. A liquid level detection device as claimed in claim 7, wherein: the static capacitance matching circuit of the sampling needle comprises a capacitor C2, one end of the capacitor C2 is connected with a GND power supply network, and the other end of the capacitor C2 is connected with one signal input pin 3 of a Schmidt phase inverter U3.
9. A liquid level detection device as claimed in claim 8, wherein: the logic operation circuit comprises an exclusive-OR gate U2 and a capacitor C4, wherein the capacitor C4 is a power supply decoupling capacitor of the exclusive-OR gate U2, one end of the capacitor C4 is connected with a GND power supply network, and the other end of the capacitor C4 is connected with a power supply pin 5 and a 5V power supply network of the exclusive-OR gate U2; one path of oscillation circuit signal output pin 7 of the Schmidt inverter U3 is connected with the signal input pin 1 of the exclusive-OR gate U2; a signal output pin 5 of a static capacitance matching circuit of a sampling needle of the Schmidt phase inverter U3 is connected with a signal input pin 2 of the exclusive-OR gate U2; a pin 3 of the exclusive-OR gate U2 is connected with a GND power supply network; the output pin 4 of the exclusive or gate is connected with a back-end processing circuit.
10. A liquid level detection device as claimed in claim 9, wherein: the type of the exclusive-OR gate U2 is TC7S86F, and the back-end processing circuit comprises an MCU of which the type is STM32F103CBT 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310010570.8A CN115790777B (en) | 2023-01-05 | 2023-01-05 | Liquid level detection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310010570.8A CN115790777B (en) | 2023-01-05 | 2023-01-05 | Liquid level detection device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115790777A true CN115790777A (en) | 2023-03-14 |
| CN115790777B CN115790777B (en) | 2023-05-02 |
Family
ID=85428548
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310010570.8A Active CN115790777B (en) | 2023-01-05 | 2023-01-05 | Liquid level detection device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115790777B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08220161A (en) * | 1995-02-16 | 1996-08-30 | A & T:Kk | Detecting device of capacitance and sensor using the device |
| CN204373736U (en) * | 2015-01-19 | 2015-06-03 | 南昌百特生物高新技术股份有限公司 | Based on the detecting liquid level circuit of phaselocked loop |
| CN205808504U (en) * | 2016-05-30 | 2016-12-14 | 深圳市锦瑞生物科技有限公司 | A kind of aspirating needle liquid level sensor |
| CN109579943A (en) * | 2019-01-25 | 2019-04-05 | 广州眺望电子科技有限公司 | A kind of liquid detection device and method |
| CN114264351A (en) * | 2021-12-15 | 2022-04-01 | 嘉兴凯实生物科技股份有限公司 | Capacitance liquid level detection system based on crystal oscillation method |
-
2023
- 2023-01-05 CN CN202310010570.8A patent/CN115790777B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08220161A (en) * | 1995-02-16 | 1996-08-30 | A & T:Kk | Detecting device of capacitance and sensor using the device |
| CN204373736U (en) * | 2015-01-19 | 2015-06-03 | 南昌百特生物高新技术股份有限公司 | Based on the detecting liquid level circuit of phaselocked loop |
| CN205808504U (en) * | 2016-05-30 | 2016-12-14 | 深圳市锦瑞生物科技有限公司 | A kind of aspirating needle liquid level sensor |
| CN109579943A (en) * | 2019-01-25 | 2019-04-05 | 广州眺望电子科技有限公司 | A kind of liquid detection device and method |
| CN114264351A (en) * | 2021-12-15 | 2022-04-01 | 嘉兴凯实生物科技股份有限公司 | Capacitance liquid level detection system based on crystal oscillation method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115790777B (en) | 2023-05-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102866322B (en) | A kind of touching device detection method | |
| CN102902393B (en) | Detecting electrode Array Control Circuit, control method and touch detection system thereof | |
| CN110286246A (en) | Secondary speed detection method and device | |
| CN105675725A (en) | Ultrasonic pulse transmitting-receiving system based on FPGA control | |
| CN109995356A (en) | A kind of signal-isolated transmission circuit based on capacitor | |
| CN109581272A (en) | A kind of direct current energy meter detection system | |
| CN202757999U (en) | Frequency and phase position detector for AC power supply | |
| CN210721039U (en) | Calibration device and measurement system of time interval measurement equipment | |
| CN115790777B (en) | Liquid level detection device | |
| CN104678134B (en) | AC constant-current source, internal resistance of cell detection means and cell tester | |
| CN110058087A (en) | A kind of fully differential structure small capacitance detection chip of strong anti-interference super low-power consumption | |
| CN102609122B (en) | There is two contactor control device and the method for piezoelectricity touch-control and electromagnetic touch | |
| CN107101596A (en) | Range sensor and 3D rendering sensor | |
| CN104270219B (en) | A kind of device for analyzing IRIG-B time symbols | |
| CN102979948A (en) | Electromagnetic valve closing-time moment detection circuit of diesel engine electric control system | |
| CN110345973A (en) | Current vortex sensor and detection method | |
| CN212321713U (en) | High-speed tube voltage drop detection circuit based on parallel capacitor | |
| CN101576524B (en) | Detection device for dynamical contacting impedance of magnetic reed pipe and detection method thereof | |
| CN203204073U (en) | Digital phase-difference measuring instrument | |
| CN202282326U (en) | Digital frequency meter applied to radio frequency multipole rod | |
| CN202677617U (en) | Motor vehicle characteristic data acquisition analyzer | |
| CN211206631U (en) | Four-phase orthogonal square wave signal generating device | |
| CN106597067B (en) | The voltage or current measuring device and method of a kind of random waveform arbitrary point | |
| CN104697605A (en) | Intelligent liquid level induction circuit and device | |
| CN111025114A (en) | Full-automatic testing arrangement of integrated circuit high frequency electric parameter characteristic |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |