A high-precision MEMS silicon resonant pressure sensor digitizing debugging device and a debugging method thereof

Abstract

The application relates to a high-precision MEMS silicon resonance pressure sensor digital debugging device which is composed of a silicon resonance pressure sensor, a single-chip interface circuit, a measuring device, an FPGA / MCU control board and an upper computer; a Zener breakdown tube is selected in the upper computer to adjust a unit array, a test target value is set according to actual characteristics of the sensor, serial test writing is carried out, the measuring device measures an electric parameter target value of the single-chip interface circuit after reading operation of the unit array is completed, actual value and the target value are consistent, debugging is finished, otherwise, the debugging is restarted. The application has the advantages that on-chip adjustment and solidification of the electric performance parameters of the circuit are realized without increasing additional cost and the size of the sensor, the whole debugging loop is digitized, the degree of automation is high, the debugging efficiency is high, and the application is easy to operate; the performance of the Zener breakdown tube is stable after reverse breakdown, there is no hidden danger of high-temperature leakage loss of the storage unit, and the reliability and engineering applicability are further improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of MEMS pressure sensors, in particular to a high-precision MEMS silicon resonant pressure sensor digital debugging method. BACKGROUND

[0002] A pressure sensor is a sensor for converting a measured pressure into an electric signal, wherein a MEMS silicon resonant pressure sensor is a sensor for directly outputting a frequency electric signal to represent a measured pressure based on a MEMS resonator closed-loop control principle. The MEMS silicon resonant pressure sensor is a pressure sensor with the highest comprehensive precision at present, and is widely applied in an aviation atmospheric data measurement system, a ground pressure controller and a meteorological measurement device due to the advantages of high precision, good stability and strong frequency output anti-interference capability.

[0003] The MEMS silicon resonant pressure sensor is generally composed of a sensor sensitive structure and an interface circuit. When the MEMS silicon resonant pressure sensor sensitive structure is manufactured, machining errors are difficult to avoid, and the resonant frequency, sensitivity and temperature characteristics of the sensitive structure are prone to deviation, and non-ideal factors such as output nonlinearity are caused, so that the parameter consistency of the sensor sensitive structure is poor, and individual differences exist to different degrees. Therefore, in the whole table debugging process of the pressure sensor sensitive structure and the interface circuit, the electric performance indexes of the sensor interface circuit are adjusted according to the parameter characteristics of the sensor sensitive structure, so that the sensitive structure and the interface circuit parameter design are matched, and the whole silicon resonant pressure sensor closed-loop system stable amplitude-stable frequency control is realized.

[0004] After searching the existing patents, a compensation method for a silicon resonant pressure sensor (publication number CN106932125B) is found. The silicon resonant pressure sensor is measured by using a single-chip microcomputer timer to realize synchronous frequency measurement, so that the frequencies of two resonators are synchronously collected, the measurement precision of the pressure sensor is improved, and a nonlinear model of a least square support vector machine is used to realize temperature compensation in a full temperature and full pressure range. The method is used for the temperature performance and nonlinear calibration and compensation link of the whole sensor, and belongs to a post-process debugging procedure. The present application mainly aims at the whole table debugging link of the pressure sensor sensitive structure and the interface circuit, can realize the parameter rapid adaptation between the sensor sensitive structure and the interface circuit, and belongs to a front-process debugging procedure. The traditional whole sensor debugging method is to repeatedly replace resistors and capacitors in the interface circuit to realize parameter adaptation. The debugging method has high cost and low debugging efficiency, and is not suitable for large-scale engineering production of the sensor. No similar high-precision MEMS silicon resonant pressure sensor whole table debugging method is found. SUMMARY

[0005] The application aims to provide a high-precision MEMS silicon resonant pressure sensor digital debugging device and a debugging method, which adjusts the electrical performance parameter indexes of the interface circuit in a digital manner, matches the sensor sensitive structure parameters, completes the solidification of the electrical performance parameters of the interface circuit, and stores the trimming coefficients on the chip, so as to realize the closed-loop control and stable work of the entire silicon resonant pressure sensor, greatly improve the parameter index adaptability of the sensor sensitive structure and the interface circuit, the adjustability and engineering applicability of the sensor whole meter, and effectively reduce the sensor whole meter debugging time and cost.

[0006] The technical solution adopted by the application to solve the technical problems is:

[0007] I. A high-precision MEMS silicon resonant pressure sensor digital debugging device, characterized by comprising a silicon resonant pressure sensor sensitive structure, a single-chip interface circuit, a measuring device, an FPGA / MCU control board, and an upper computer control module.

[0008] The upper computer control module comprises a test writing control module, a reading control module, and a burn writing control module.

[0009] The single-chip interface circuit comprises a capacitance detection circuit, a peak detection circuit, a PI control circuit, a phase-shifting circuit, and a driving circuit, a high-voltage charge pump and a temperature sensor, a filter circuit, a square wave signal circuit, a frequency output circuit, and a Zener diode trimming unit array.

[0010] The capacitance detection circuit converts the capacitance change of the silicon resonant pressure sensor sensitive structure into a sinusoidal voltage signal, the sinusoidal signal is subjected to full-wave rectification and amplitude stabilization control through the peak detection circuit and the PI control circuit, and finally the electrostatic excitation voltage signal is generated by the phase-shifting circuit and the driving circuit, and is fed back to the silicon resonant pressure sensor sensitive structure to realize the amplitude-stable and frequency-stable control of the entire resonant loop; another sinusoidal measurement signal is converted into a square wave signal through the filter circuit, the square wave signal circuit, and the frequency output circuit, and the frequency signal representing the pressure value detected by the sensor is output to the measuring device.

[0011] The high-voltage charge pump and the temperature sensor provide direct-current high voltage and temperature information for improving and compensating the detection sensitivity of the pressure sensor.

[0012] The Zener diode trimming unit array is composed of a group of Zener diode trimming units, which can trim the parameter indexes of each functional module in the single-chip interface circuit, including loop gain, loop phase compensation, filter characteristics, excitation voltage amplitude, and proportional integral coefficient.

[0013] 2) The Zener diode trimming unit is composed of a test writing module, a burn writing module, and a reading module.

[0014] The trial writing module comprises a first inverter and a second inverter, a third inverter and a fourth inverter, which form a state latch respectively, and a first switch tube to an eighth switch tube, which together form a register. The input and output ends of the first inverter and the second inverter are interconnected. The source of the first switch tube is grounded, and the drain is connected to the source of the second switch tube. The source of the second switch tube is connected to the input end of the first inverter. The output end of the first inverter is connected to the source of the third switch tube. The drain of the third switch tube is connected to the source of the fourth switch tube. The drain of the fourth switch tube is grounded. The gates of the first and fourth switch tubes are data input + and data input - respectively. The gates of the second and third switch tubes are trial writing control A respectively.

[0015] The input and output ends of the third inverter and the fourth inverter are interconnected. The source of the fifth switch tube is connected to the input end of the third inverter, and the drain is connected to the source of the sixth switch tube. The drain of the sixth switch tube is grounded. The source of the seventh switch tube is grounded, and the drain is connected to the source of the eighth switch tube. The drain of the eighth switch tube is connected to the output end of the third inverter as a unit output end. The gates of the fifth and eighth switch tubes are trial writing control B respectively. The gates of the sixth and seventh switch tubes are connected to the input end and the output end of the first inverter respectively.

[0016] The burning module is composed of an AND gate, a fourteenth switch tube, a Zener diode, a resistor, a thirteenth switch tube, a large current channel power supply and a logic level power supply. One input end of the AND gate is connected to the output end of the third inverter, and the other input end is burning control Z. The output end of the AND gate is connected to the gate of the fourteenth switch tube. The drain of the fourteenth switch tube is connected to the anode of the Zener diode, and the source is grounded. The cathode of the Zener diode is connected to the large current channel power supply and the logic level power supply. One end of the resistor is connected to the drain of the fourteenth switch tube, and the other end is connected to the gate of the thirteenth switch tube. The drain of the thirteenth switch tube is connected to the logic level power supply.

[0017] The reading module comprises a fifth inverter and a sixth inverter connected in series at the beginning and the end, and further comprises a ninth switch tube, a tenth switch tube, an eleventh switch tube and a twelfth switch tube. The source of the ninth switch tube is connected to the input end of the third inverter, and the drain is connected to the source of the tenth switch tube. The gate of the tenth switch tube is connected to the input end of the fifth switch tube inverter, and the drain is connected to the drain of the twelfth switch tube and grounded. The gate of the twelfth switch tube is connected to the output end of the fifth switch tube inverter, and the source is connected to the drain of the eleventh switch tube. The gate of the eleventh switch tube is connected to the gate of the ninth switch tube as reading control R2, and the drain is connected to the output end of the third switch tube inverter.

[0018] In addition, the 15th switch tube and the 16th switch tube are arranged, the drain of the 15th switch tube is connected with the drain of the 14th switch tube, the drain of the 16th switch tube is connected with the source of the 13th switch tube, the gates of the 15th switch tube and the 16th switch tube are connected in parallel as reading control R1, and the sources of the 15th switch tube and the 16th switch tube are grounded;

[0019] 4) the Zener breakdown tube trimming unit array is composed of at least two Zener breakdown tube trimming units, each Zener breakdown tube trimming unit comprises test writing control A / B, data input terminal + / -, power output terminal, burning writing control Z, reading control R1 / R2, the data input terminal + / - of the trimming unit 1 serves as the data input IN of the whole array, the unit output of each trimming unit serves as the data input terminal + / - of the next trimming unit, the unit output terminal of the last trimming unit 4 serves as the data state output of the whole array, the test writing control A / B of each trimming unit is connected in parallel as the test writing control W of the whole array, and the reading control R1 / R2 of each trimming unit is connected in parallel as the reading and writing control R of the whole array.

[0020] The output terminal of each trimming unit in the Zener breakdown tube trimming unit array is connected with the input terminal of the next trimming unit, so as to form a serially controlled data shift register. After the Zener breakdown tube trimming unit array is operated through test writing, reading, burning writing and testing, the states of the Zener breakdown tube trimming units are output in parallel.

[0021] Secondly, the application further provides a high-precision MEMS silicon resonant pressure sensor digital debugging method, which comprises the following steps:

[0022] S1, the high-precision MEMS silicon resonant pressure sensor digital debugging device is used.

[0023] S2, the upper computer control module is used to automatically or manually complete the debugging in sequence according to the debugging requirements;

[0024] S3, the upper computer control module and the FPGA / MCU control board establish a communication mechanism, and the FPGA / MCU control board starts the debugging work after receiving the debugging instruction of the upper computer;

[0025] S4, the FPGA / MCU control board and the single-chip interface circuit establish communication and initialize operation, the Zener breakdown tube trimming unit array in the single-chip interface circuit adopts a data serial test writing and parallel reading mode, if a plurality of Zener breakdown tube trimming units are operated in parallel, the difference between the tubes is easy to cause the phenomenon that individual Zener breakdown tubes cannot be reversely broken down, therefore, in order to ensure the success rate of the reverse breakdown conduction, the Zener breakdown tube trimming unit array is operated in the burning writing mode only once, that is, the reverse breakdown operation is performed on only one Zener breakdown tube at a time.

[0026] S5、In the host computer control module, select the Zener diode breakdown tube tuning unit array of tuning items, such as loop gain, phase compensation, filter characteristics, excitation voltage amplitude and proportional integral coefficient, while setting the test target value according to the actual characteristics of the sensor, such as the resonant frequency value of the silicon resonant pressure sensor, the detection sine wave amplitude, the excitation voltage amplitude, the detection-excitation signal phase difference, the resonant frequency value range 10kHz~40kHz, the detection sine wave amplitude range 0.5V~2V, the excitation voltage amplitude 2V~3.3V, and the detection-excitation signal phase difference range 0°~10°, start the serial test writing work;

[0027] The test writing data is written by the data input end + and the data input end - of the register, and the test writing control A signal and the test writing control B signal are two-phase non-overlapping clocks. After 1 clock period, 1 tuning unit test writing is completed. An array of n tuning units needs n clock periods to complete all test writing operations. During the entire test writing process, the reading module and the burning module do not work;

[0028] S6、When the test writing operation of the tuning unit array is completed, the FPGA / MCU control board establishes communication with the measuring device and initializes the operation, and sets the target value. The measuring device measures and monitors the electrical parameter target value of the single-chip interface circuit in real time, including the resonant frequency value, the detection sine wave amplitude, the excitation voltage amplitude, and the detection-excitation signal phase difference. The actual test result is returned to the FPGA / MCU control board. The actual test result and the set test target value are compared, and the comparison result is transmitted to the host computer control module. If the actual test result is consistent with the set test target value, it indicates that the test writing parameter meets the debugging requirements of the sensor whole table, and the test writing is successful. Otherwise, start the test writing operation again until the set test target value requirement is met;

[0029] S7、When the test writing operation of the tuning unit array is completed, start the burning operation. Before the burning control module works, the burning bit needs to be determined again, and the flag logic "1" is input through the data input end + / - of the shift register. When the burning control Z signal is "1" at the same time, the switch tube 14 in the burning module of the Zener tuning unit is turned on, and a 12V direct current large current channel power supply 1 is used to form a large current path, and the duration needs to be maintained for more than 150us. At this time, the Zener diode is reversely broken down. Note that the Zener diode burning operation is irreversible, and cannot be restored after reverse breakdown. Each Zener diode tuning unit can only perform a burning operation once;

[0030] S8, when the write operation of the trimming unit array is completed, the read operation is started, when the read control R1 signal and the read control R2 signal are both set to "1", the read control module starts to work, if the Zener diode is not reversely broken down, the output end of the Zener diode trimming unit outputs "0", otherwise, "1" is outputted;

[0031] S9, when the read operation of the trimming unit array is completed, the measuring device 3 measures the electrical parameter target value of the single-chip interface circuit 2 again, the output state of the trimming unit array is verified, and the actual test result is returned to the FPGA / MCU control board, the actual test result is compared with the set test target value, and the result is returned to the upper computer, if the actual test result is consistent with the set test target value, the debugging work is completed, otherwise, the write operation is started again, the above steps are repeated until the test target value requirement is met.

[0032] After the write operation, the write operation, the read operation and the test verification, the Zener diode trimming unit array is completed, and the trimming data storage function is also completed. After the MEMS silicon resonant pressure sensor is powered on again, the trimming unit outputs corresponding state information, and the state information is solidified. The high-precision MEMS silicon resonant pressure sensor digitalization debugging is completed. The trimming method can improve the debugging efficiency of the sensor and reduce the cost.

[0033] The high-precision MEMS silicon resonant pressure sensor digitalization debugging method based on the integrated circuit BCD (Bipolar-CMOS-DMOS) process, the Zener diode trimming basic unit and the array are integrated and constructed in the sensor single-chip interface circuit, the on-chip trimming and solidification of the circuit electrical performance parameters are realized without increasing the additional cost and the sensor size; the whole debugging loop is digitized and has high automation degree, high debugging efficiency and easy operation; meanwhile, the performance of the Zener diode is stable after being reversely broken down, and there is no hidden danger of high-temperature leakage of the storage unit, which further improves the reliability and engineering applicability of the high-precision MEMS silicon resonant pressure sensor. BRIEF DESCRIPTION OF DRAWINGS

[0034] The application will be further described below in combination with the drawings and embodiments:

[0035] Figure 1 is the Zener diode structure section view based on the integrated circuit BCD process of the application;

[0036] Figure 2 is the Zener diode trimming unit circuit structure diagram of the application;

[0037] Figure 3 is the 4-bit Zener diode trimming unit array schematic diagram of the application;

[0038] Figure 4 This is a schematic diagram of the structure of a high-precision MEMS silicon resonant pressure sensor digital debugging device according to the present invention. Implementation

[0039] Example 1: A high-precision MEMS silicon resonant pressure sensor digital debugging device, comprising the following components:

[0040] 1. For example Figure 4 As shown, the pressure sensor digital debugging device consists of a silicon resonant pressure sensor sensitive structure, a single-chip interface circuit, a measuring device, an FPGA / MCU control board, and a host computer control module, and the electrical connections are completed as required.

[0041] The sensitive structure of the silicon resonant pressure sensor oscillates under the influence of noise and electrostatic force, transmitting the detection signal to the monolithic interface circuit.

[0042] The single-chip interface circuit consists of a capacitance detection circuit, a peak detection circuit, a PI control circuit, a phase shifting circuit and a drive circuit, a high-voltage charge pump and a temperature sensor, a filter circuit, a square wave signal, a frequency output circuit, and a Zener breakdown tube adjustment unit array.

[0043] The capacitance change of the sensitive structure of the silicon resonant pressure sensor is converted into a sinusoidal voltage signal through a capacitance detection circuit. The sinusoidal signal is then rectified and amplitude stabilized by a peak detection circuit and a PI control circuit. Finally, an electrostatic excitation voltage signal is generated by a phase shift circuit and a drive circuit, and fed back to the sensitive structure of the silicon resonant pressure sensor to achieve amplitude-frequency stabilization control of the entire resonant closed loop. Another sinusoidal measurement signal is converted into a square wave signal through a filter circuit, a square wave signal, and a frequency output circuit, and outputs a frequency signal that represents the magnitude of the pressure value detected by the sensor.

[0044] A high-voltage charge pump and a temperature sensor provide DC high voltage and temperature information to improve and compensate for the detection sensitivity of the pressure sensor.

[0045] The Zener breakdown transistor tuning unit array has a total of 52 tuning units, which can tune the parameters of various functional modules in the monolithic interface circuit, including loop gain (10 to 200 times), loop phase compensation (0° to 90°), filtering characteristics (low-pass filter cutoff frequency range 10Hz to 10kHz), excitation voltage amplitude (2V to 3.3V), and proportional-integral coefficient (proportional coefficient 1 to 20 times).

[0046] The existing high-precision MEMS silicon resonant pressure sensor interface circuit mostly adopts analog discrete devices such as operational amplifiers, and is realized by building a PCB circuit board, which has problems such as large size, high power consumption, and high cost, and the adaptability of the analog circuit board to the sensitive structure of the pressure sensor and the adjustability of the whole watch also have limitations.

[0047] The monolithic interface circuit 2 of the application integrates the functions of the original interface circuit board and the Zener breakdown tube trimming unit array on the same chip, solving the problem of the MEMS silicon resonant pressure sensor engineering application.

[0048] 2, the cross-sectional structure of the Zener breakdown tube is shown in Figure 1 The P-type buried layer and the N-type epitaxial layer are grown on the P-type substrate, the N-well is formed by ion implantation, the breakdown tube cathode and the breakdown tube anode are formed, and the electrical isolation is realized by the field oxide layer. The Zener breakdown tube is in a reverse bias state during normal operation of the circuit, which is an open circuit, and the voltage across each Zener breakdown tube cannot exceed two-thirds of the junction breakdown voltage; after the burn-write operation, the Zener breakdown tube is short-circuited due to the large current reverse breakdown, so the Zener breakdown tube can be used as the core element of the circuit trimming unit. According to the trimming requirements of the sensor monolithic interface circuit, the Zener breakdown tube trimming unit and array are designed to adjust the electrical performance parameters of the sensor monolithic interface circuit, such as loop gain, loop phase compensation, filter characteristics, excitation voltage amplitude and proportional integral coefficient.

[0049] 3, the Zener breakdown tube trimming unit is shown in Figure 2 It is composed of three parts: a test writing module, a burn writing module and a reading module.

[0050] The test writing module includes a first inverter and a second inverter, a third inverter and a fourth inverter, which form a state latch respectively, and a first switch tube to an eighth switch tube, which together constitute a register. The input and output ends of the first inverter and the second inverter are interconnected, the source of the first switch tube is grounded, the drain is connected to the source of the second switch tube, the source of the second switch tube is connected to the input end of the first inverter, the output end of the first inverter is connected to the source of the third switch tube, the drain of the third switch tube is connected to the source of the fourth switch tube, the drain of the fourth switch tube is grounded, the gates of the first and fourth switch tubes are data input + and data input - respectively, and the gates of the second and third switch tubes are test writing control A.

[0051] The input and output ends of the third and fourth inverters are interconnected, the source of the fifth switch tube is connected to the input end of the third inverter, the drain of the fifth switch tube is connected to the source of the sixth switch tube, the drain of the sixth switch tube is connected to the ground, the source of the seventh switch tube is connected to the ground, the drain of the seventh switch tube is connected to the source of the eighth switch tube, the drain of the eighth switch tube is connected to the output end of the third inverter as a unit output end, the gates of the fifth and eighth switch tubes are respectively the test writing control B, and the gates of the sixth and seventh switch tubes are respectively connected to the input end and output end of the first inverter;

[0052] The test writing data is written by the data input end + / - of the register, the test writing control A signal and the test writing control B signal are two-phase non-overlapping clock signals, the test writing data is transmitted to the unit output end after one clock cycle, the test writing operation is completed, and the reading module and the burning module do not work during the whole test writing process.

[0053] The burning module is composed of an AND gate, a fourteenth switch tube, a Zener diode, a resistor, a thirteenth switch tube, a large current channel power supply and a logic level power supply, one input end of the AND gate is connected to the output end of the third inverter, the other input end is the burning control Z, the output end of the AND gate is connected to the gate of the fourteenth switch tube, the drain of the fourteenth switch tube is connected to the anode of the Zener diode, the source is connected to the ground, the cathode of the Zener diode is connected to the large current channel power supply and the logic level power supply, one end of the resistor is connected to the drain of the fourteenth switch tube, the other end is connected to the gate of the thirteenth switch tube, the drain of the thirteenth switch tube is connected to the logic level power supply.

[0054] Before the burning module works, it is necessary to confirm the burning operation again. The logic high level direct current power required by the power supply is provided, and the logic high level "1" representing the burning operation flag is input through the register data input end + / - in the test writing module. When the burning control Z signal is set to the logic high level "1", the output of the AND gate is the logic high level "1" at this time, the switch tube 14 is turned on, the direct current high voltage is provided by the large current channel power supply 1 to form a large current path, and the Zener diode will be reversely broken down. Since the Zener diode burning operation is irreversible, it cannot be restored after being reversely broken down, so each Zener diode trimming unit can only perform a burning operation.

[0055] The reading module comprises a 5th inverter and a 6th inverter connected in series, and further comprises a 9th switch tube, a 10th switch tube, an 11th switch tube and a 12th switch tube, the source of the 9th switch tube is connected to the input of the 3rd inverter, the drain of the 9th switch tube is connected to the source of the 10th switch tube, the gate of the 10th switch tube is connected to the input of the 5th inverter, the drain of the 10th switch tube is connected to the drain of the 12th switch tube and grounded, the gate of the 12th switch tube is connected to the output of the 5th inverter, the source of the 12th switch tube is connected to the drain of the 11th switch tube, the gate of the 11th switch tube is connected to the gate of the 9th switch tube as a reading control R2, and the drain of the 11th switch tube is connected to the output of the 3rd inverter;

[0056] In addition, a 15th switch tube and a 16th switch tube are further provided, the drain of the 15th switch tube is connected to the drain of the 14th switch tube, the drain of the 16th switch tube is connected to the source of the 13th switch tube, the gates of the 15th switch tube and the 16th switch tube are connected in parallel as a reading control R1, and the sources of the 15th switch tube and the 16th switch tube are grounded;

[0057] When the reading control R1 signal and the reading control R2 signal are both set to a logic high level "1", the reading module 3 starts to work. If the Zener diode breakdown tube 1 is not reversely broken down, the Zener diode breakdown tube trimming unit output end outputs "0", otherwise, "1" is output.

[0058] After the trial writing operation, the burning writing operation and the reading operation, the Zener diode breakdown tube trimming unit works completely, and the Zener diode breakdown tube trimming unit output trimming state result is written into the register solidification after the circuit is powered on again, so that the storage function of the trimming data is realized.

[0059] In order to improve the robustness of the high-precision MEMS silicon resonant pressure sensor and the Zener diode breakdown tube trimming unit, and shorten the reading time of the circuit trimming state result and the response time of the sensor, the Zener diode breakdown tube trimming unit array adopts a structure of serial trial writing, parallel reading and 1-bit burning writing, the number of the trimming units is determined by the trimming demand of the single-chip interface circuit, 1 trimming unit controls 1 trimming switch, so as to control the number and size of the resistors and capacitors connected in the function modules of the single-chip interface circuit.

[0060] 4, the Zener diode breakdown tube trimming unit array of the embodiment is as shown in Figure 3As shown, the tuning units 1, 2, 3, and 4 are composed, each of which includes a test write control A / B, a data input terminal + / -, a power output terminal, a burn write control Z, a read control R1 / R2, the data input terminal + / - of the tuning unit 1 serving as the data input IN of the whole array, the unit output of each tuning unit serving as the data input terminal + / - of the next tuning unit, the unit output terminal of the last tuning unit 4 serving as the data state output of the whole array, the test write control A / B of each tuning unit serving as the test write control W of the whole array in parallel, and the read control R1 / R2 of each tuning unit serving as the read / write control R of the whole array in parallel.

[0061] The output terminal of each tuning unit in the tuning array is connected to the input terminal of the next tuning unit, thereby forming a serially controlled data shift register. After the Zener diode tuning unit array is operated through test writing, reading, burn writing, and testing, the states of the Zener diode tuning units are output in parallel.

[0062] II. Embodiment Two

[0063] The application also provides a high-precision MEMS silicon resonant pressure sensor digital debugging method, as shown in the accompanying drawings, comprising the following steps: Figure 4 As shown, the method comprises the following steps:

[0064] S1. A high-precision MEMS silicon resonant pressure sensor digital debugging device according to Embodiment 1 is used.

[0065] S2. The debugging is implemented by the upper computer control module 5, which includes three parts, i.e., a test write control module 5.1, a read control module 5.2, and a burn write control module 5.3, and can be automatically or manually completed in sequence according to the debugging needs.

[0066] S3. The upper computer control 5 and the FPGA / MCU control board 4 establish a communication mechanism, and the debugging work is started after the FPGA / MCU control board 4 receives the debugging instruction from the upper computer.

[0067] S4. The FPGA / MCU control board 4 establishes communication with the single-chip interface circuit 2 and initializes the operation. The Zener diode tuning unit array in the single-chip interface circuit 2 adopts a data serial test writing and parallel reading mode. If multiple tuning units are operated in parallel, it is easy to cause the phenomenon that individual Zener diodes cannot be reversely broken down due to the difference between the diodes. Therefore, in order to ensure the success rate of the reverse breakdown conduction, only one tuning unit in the Zener diode tuning unit array is operated for burn writing each time, i.e., only one Zener diode is operated for reverse breakdown each time.

[0068] S5, in the host computer control module 5, the selection of zener breakdown tube trimming unit array of trimming project, such as loop gain, phase compensation, filter characteristics, excitation voltage amplitude and proportional integral coefficient, etc., while according to the sensor actual characteristic set test target value, such as silicon resonant pressure sensor resonant frequency value, detection of sinusoidal amplitude, excitation voltage amplitude, detection-excitation signal phase difference, etc., the resonant frequency value range 10kHz~40kHz, the detection of sinusoidal amplitude range 0.5V~2V, the excitation voltage amplitude 2V~3.3V, the detection-excitation signal phase difference range 0°~10°, start to write serially work;

[0069] The test write data is written by the data input end + and the data input end of the register, and the test write control A signal and the test write control B signal are two-phase non-overlapping clock. After 1 clock period, 1 trimming unit test write is completed. The array composed of n trimming units needs n clock periods to complete all test write operations. During the whole test write process, the reading module and the burning module do not work.

[0070] S6, when the test write operation of the trimming unit array is completed, the FPGA / MCU control board 4 establishes communication with the measuring device 3 and initializes the operation, and sets the target value. The measuring device 3 measures and monitors the electrical parameter target value of the single-chip interface circuit 2 in real time, including the resonant frequency value, the detection of sinusoidal amplitude, the excitation voltage amplitude, and the detection-excitation signal phase difference. The actual test result is returned to the FPGA / MCU control board 4. The actual test result and the set test target value are compared, and the comparison result is transmitted to the host computer control module 5. If the actual test result is consistent with the set test target value, it indicates that the test write parameter meets the debugging requirements of the sensor whole table, and the test write is successful. Otherwise, the test write operation is restarted until the set test target value requirement is met.

[0071] S7, when the test write operation of the trimming unit array is completed, the burning operation is started. Before the burning control module works, the burning bit needs to be determined again, and the flag logic "1" is input through the data input end + / - of the shift register. When the burning control Z signal is "1" at the same time, Figure 2 The switch tube 14 in the formula is turned on, and a 12V DC power supply 1 is used to form a large current path, and the duration needs to be kept for more than 150us. At this time, the zener breakdown tube is reversely broken down. It is noted that the zener breakdown tube burning operation is irreversible, and cannot be restored after reverse breakdown. Therefore, each zener breakdown tube trimming unit can only be burned once;

[0072] S8, when the write operation of the trimming unit array is completed, the read operation is started. When the read control R1 signal and the read control R2 signal are both set to "1", the read control module starts to work. If the Zener diode is not reversely broken down, the Zener diode trimming unit output end outputs "0", otherwise, it outputs "1";

[0073] S9, when the read operation of the trimming unit array is completed, the measuring device 3 measures the electrical parameter target value of the single-chip interface circuit 2 again, and verifies the output state of the trimming unit array, and returns the actual test result to the FPGA / MCU control board 4. The actual test result is compared with the set test target value, and then returned to the upper computer. If the actual test result is consistent with the set test target value, the debugging work is completed, otherwise, the write operation is started again, and the above steps are repeated until the test target value requirement is met.

[0074] After the write operation, the write operation, the read operation and the test verification, the Zener diode trimming unit array completes the debugging operation, and also completes the trimming data storage function. After the MEMS silicon resonant pressure sensor is powered on again, each trimming unit outputs corresponding state information, and the state information is solidified. The high-precision MEMS silicon resonant pressure sensor completes the whole table digital debugging. The trimming method can improve the debugging efficiency of the sensor whole table and reduce the cost.

[0075] The above is only a preferred embodiment of the present application, and does not limit the present application in any form; any person skilled in the art can use the above disclosed method and technical content to make many possible changes and modifications to the technical solution of the present application, or modify it into equivalent embodiments. Therefore, any simple modification, equivalent replacement, equivalent change and modification of the above embodiments according to the technical essence of the present application, all still belong to the protection scope of the present application.

Claims

1. A high-precision MEMS silicon resonant pressure sensor digital debugging device, characterized in that... It consists of a silicon resonant pressure sensor sensing structure, a single-chip interface circuit, a measuring device, an FPGA / MCU control board, and a host computer control module; The host computer control module includes three parts: a trial writing control module, a reading control module, and a burning control module. The monolithic interface circuit consists of a capacitance detection circuit, a peak detection circuit, a PI control circuit, a phase shifting circuit and a drive circuit, a high-voltage charge pump and a temperature sensor, a filter circuit, a square wave signal circuit, a frequency output circuit, and a Zener breakdown tube adjustment unit array. The capacitance detection circuit converts the capacitance change of the sensitive structure of the silicon resonant pressure sensor into a sinusoidal voltage signal. The sinusoidal signal is then rectified and amplitude stabilized by the peak detection circuit and the PI control circuit. Finally, the phase shift circuit and the drive circuit generate an electrostatic excitation voltage signal, which is fed back to the sensitive structure of the silicon resonant pressure sensor to achieve amplitude-frequency stabilization control of the entire resonant closed loop. Another sinusoidal measurement signal is converted into a square wave signal by the filter circuit, the square wave signal circuit and the frequency output circuit, and outputs a frequency signal that represents the magnitude of the pressure value detected by the sensor to the measuring device. A high-voltage charge pump and a temperature sensor provide DC high voltage and temperature information to improve and compensate for the detection sensitivity of the pressure sensor. The Zener diode tuning unit array, composed of a group of Zener diode tuning units, can tune the parameters of various functional modules in a monolithic interface circuit, including loop gain, loop phase compensation, filtering characteristics, excitation voltage amplitude, and proportional-integral coefficient. The Zener breakdown tube adjustment unit consists of three parts: a trial writing module, a programming module, and a reading module. The test write module includes inverters 1, 2, 3, and 4, which together form a state latch and, together with switches 1 through 8, constitute a register. The input and output terminals of inverters 1 and 2 are interconnected. The source of switch 1 is grounded and its drain is connected to the source of switch 2. The source of switch 2 is connected to the input terminal of inverter 1. The output terminal of inverter 1 is connected to the source of switch 3. The drain of switch 3 is connected to the source of switch 4. The drain of switch 4 is grounded. The gates of switches 1 and 4 are the data input + and data input - terminals, respectively. The gates of switches 2 and 3 are the test write control A terminals. The input and output terminals of the 3rd and 4th inverters are interconnected. The source of the 5th switch is connected to the input terminal of the 3rd inverter, and its drain is connected to the source of the 6th switch. The drain of the 6th switch is grounded. The source of the 7th switch is grounded, and its drain is connected to the source of the 8th switch. The drain of the 8th switch is connected to the output terminal of the 3rd inverter as the unit output terminal. The gates of the 5th and 8th switches are respectively the test write control B. The gates of the 6th and 7th switches are respectively connected to the input and output terminals of the 1st inverter. The programming module consists of an AND gate, a 14th switch transistor, a Zener diode, a resistor, a 13th switch transistor, a high-current channel power supply, and a logic level power supply. One input of the AND gate is connected to the output of the 3rd inverter, and the other input is the programming control Z. The output of the AND gate is connected to the gate of the 14th switch transistor. The drain of the 14th switch transistor is connected to the anode of the Zener diode, and the source is grounded. The cathode of the Zener diode is connected to the high-current channel power supply and the logic level power supply. One end of the resistor is connected to the drain of the 14th switch transistor, and the other end is connected to the gate of the 13th switch transistor. The drain of the 13th switch transistor is connected to the logic level power supply. The read module includes a 5th inverter and a 6th inverter connected in series, and also includes a 9th switch, a 10th switch, an 11th switch, and a 12th switch. The source of the 9th switch is connected to the input of the 3rd inverter, and its drain is connected to the source of the 10th switch. The gate of the 10th switch is connected to the input of the 5th inverter, and its drain is connected to the drain of the 12th switch and grounded. The gate of the 12th switch is connected to the output of the 5th inverter, and its source is connected to the drain of the 11th switch. The gate of the 11th switch is connected to the gate of the 9th switch as read control R2, and its drain is connected to the output of the 3rd inverter. Additionally, a 15th switch and a 16th switch are provided. The drain of the 15th switch is connected to the drain of the 14th switch, and the drain of the 16th switch is connected to the source of the 13th switch. The gates of the 15th and 16th switches are connected in parallel as read control R1, and the sources of the 15th and 16th switches are grounded. The Zener breakdown tube adjustment unit array consists of at least two Zener breakdown tube adjustment units. Each Zener breakdown tube adjustment unit includes a test write control A / B, a data input terminal + / -, a power output terminal, a burn control Z, and a read control R1 / R2. The data input terminal + / - of the adjustment unit (4) serves as the data input IN of the entire array. The unit output of each adjustment unit serves as the data input terminal + / - of the next adjustment unit. The unit output of the last adjustment unit (4) serves as the data status output of the entire array. The test write control A / B of each adjustment unit is connected in parallel as the test write control W of the entire array. The read control R1 / R2 of each adjustment unit is connected in parallel as the read write control R of the entire array. In the Zener breakdown tube adjustment unit array, the output of each adjustment unit is connected to the input of the next adjustment unit, forming a serially controlled data shift register. After the Zener breakdown tube adjustment unit array is operated through the functions of test writing, reading, burning, and testing, the status of each Zener breakdown tube adjustment unit is output in parallel.

2. A digital debugging method for a high-precision MEMS silicon resonant pressure sensor, comprising the following steps: S1. A high-precision MEMS silicon resonant pressure sensor digital debugging device as described in claim 1; S2, is implemented uniformly by the host computer control module and is completed automatically or manually as needed for debugging. S3. A communication mechanism is established between the host computer control module and the FPGA / MCU control board. After the FPGA / MCU control board receives the debugging command from the host computer, the debugging work starts. S4. The FPGA / MCU control board establishes communication with the single-chip interface circuit and initializes the operation. The Zener breakdown transistor adjustment unit array in the single-chip interface circuit adopts the method of serial data writing and parallel reading. Each time, only one adjustment unit in the Zener breakdown transistor adjustment unit array is burned. S5. In the host computer control module, select the adjustment items of the Zener breakdown tube adjustment unit array, including loop gain, phase compensation, filter characteristics, excitation voltage amplitude and proportional-integral coefficient. At the same time, set the test target value according to the actual characteristics of the sensor. Then, set the resonant frequency value, detection sine wave amplitude, excitation voltage amplitude, and detection-excitation signal phase difference of the silicon resonant pressure sensor. The resonant frequency value range is 10kHz~40kHz, the detection sine wave amplitude range is 0.5V~2V, the excitation voltage amplitude range is 2V~3.3V, and the detection-excitation signal phase difference range is 0°~10°. Start the serial test writing work. The test data is written from the register's data input terminals + and -. The test control signal A and test control signal B are two non-overlapping clocks. One trimming unit completes the test writing after one clock cycle. An array of n trimming units requires n clock cycles to complete all test writing operations. During the entire test writing process, the read module and the burn module do not work. S6. After completing the trial writing operation of the adjustment unit array, the FPGA / MCU control board establishes communication with the measurement equipment, initializes the operation, and sets the target value. The measurement equipment measures and monitors the target values ​​of the electrical parameters of the single-chip interface circuit in real time, including the resonant frequency value, the amplitude of the detection sine wave, the amplitude of the excitation voltage, and the phase difference between the detection and excitation signals. The actual test results are returned to the FPGA / MCU control board, and the actual test results are compared with the set test target values. The comparison results are then transmitted to the host computer control module. If the actual test results are consistent with the set test target values, it indicates that the trial writing parameters meet the debugging requirements of the entire sensor, and the trial writing is successful. Otherwise, the trial writing operation is restarted until the set test target value requirements are met. S7. After completing the trial writing operation of the trim unit array, the burning operation begins. Before the burning control module works, the burning bit needs to be determined again, and the flag logic "1" is input through the data input terminal + / - of the shift register. When the burning control Z signal is set to "1", the switch 14 in the burning module of the Zener trim unit is turned on, and the 12V DC high current channel power supply 1 is used to form a high current path. The duration needs to be maintained for more than 150us. At this time, the Zener breakdown tube is reversed and broken down. Each Zener breakdown tube trim unit can only perform one burning operation. S8. After the programming operation of the trim unit array is completed, the reading operation begins. When both the reading control R1 signal and the reading control R2 signal are set to "1", the reading control module starts to work. If the Zener breakdown tube is not broken down in the reverse direction, the Zener breakdown tube trim unit outputs "0", otherwise it outputs "1". S9. After completing the reading operation of the trim unit array, the measuring device (3) measures the electrical parameter target value of the single-chip interface circuit (2) again, verifies the output status of the trim unit array, and returns the actual test result to the FPGA / MCU control board. The actual test result is compared with the set test target value and then returned to the host computer. If the actual test result is consistent with the set test target value, the entire debugging work is over. Otherwise, the trial writing operation is restarted and the above steps are repeated until the test target value requirement is met.

3. The digital debugging method for a high-precision MEMS silicon resonant pressure sensor according to claim 2, characterized in that, After trial writing, burning, reading and testing, the entire Zener breakdown tube adjustment unit array completed the debugging operation and also completed the storage function of adjustment data. After the MEMS silicon resonant pressure sensor was powered on again, each adjustment unit output the corresponding status information and the status information was solidified. The digital debugging of the high-precision MEMS silicon resonant pressure sensor was completed.

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