Ultrasonic output current stabilization time regulation and control circuit board, regulation and control method and driving circuit

Abstract

The invention discloses an ultrasonic output current stabilization time regulation and control circuit board, a regulation and control method and a driving circuit. The circuit board comprises a multiplexing module and an operational amplification module. Wherein the multiplexing module comprises a multiplexer and a plurality of capacitors; the capacitance values of the plurality of capacitors are gradually increased; and the operational amplification module is connected with the multiplexer. According to the sound output current stabilization time regulation and control circuit board, the regulation and control method and the driving circuit, the welding quality can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of ultrasonic welding of bonding machines, and in particular to an ultrasonic output current stabilization time control circuit board, a control method and a driving circuit. Background Art

[0002] A bonder is a device used in semiconductor chip manufacturing. Its working principle is to weld metal wires, usually aluminum or gold, to metal pins on the surface of the chip. These metal wires are used to connect different parts on the chip to form a circuit.

[0003] Piezoelectric ultrasonic transducer is an energy converter that uses piezoelectric ceramics to convert electrical energy into mechanical energy. It can convert alternating electrical signals into mechanical vibrations of a certain frequency and amplitude, which are then transmitted to the welding head through a set of amplitude-changing rod devices that can change the amplitude. The welding head transmits the received vibration energy to the joint of the workpiece to be welded, thereby realizing ultrasonic welding.

[0004] Since the ultrasonic transducer has equivalent capacitance and inductance, when the ultrasonic wave is output, it takes a period of stabilization time for the current to rise from 0 mA to the set value. In the related art, the stabilization time of the ultrasonic wave output is not adjusted.

[0005] The main impacts of the stabilization time of ultrasonic output that cannot be adjusted are:

[0006] 1. When the output stabilization time is short, the current rises quickly, which easily forms a huge overshoot, causing over-welding when the solder joint contacts, severe deformation, and poor final forming of the welding surface;

[0007] 2. When the stabilization time is long, the current rises slowly. For some scenarios with short single welding time, such as when the welding material is thick aluminum wire, the stabilization time occupies a considerable proportion of the total time, and the current during the stabilization time is much smaller than the stabilization current, resulting in insufficient total welding power and weak welds.

[0008] Also, when welding metal wires of different materials, different current rise speeds are often expected. For example, gold wires require a relatively long stabilization time to smoothly reach the set value. Aluminum wires require a faster current rise speed to quickly achieve a higher power output. However, in current related ultrasonic technologies, there is no way to adjust the current stabilization time. Summary of the invention

[0009] The technical problem to be solved by the present invention is to solve the problem that the current stabilization time cannot be adjusted in the current related ultrasonic technology.

[0010] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0011] A circuit board for regulating the stable time of ultrasonic output current comprises a multiplexing module (210) and an operational amplifier module (220); wherein the multiplexing module (210) comprises a multiplexer U3 and a plurality of capacitors; and the capacitance values ​​of the plurality of capacitors gradually increase; and the operational amplifier module (220) is connected to the multiplexer U3;

[0012] Wherein, the plurality of capacitors include capacitors CS1, CS2, CS3, CS4, CS5, CS6, CS7 and capacitor CS8;

[0013] One end of capacitor CS1 is connected to pin 5 of multiplexer U3;

[0014] One end of capacitor CS2 is connected to the 4th pin of multiplexer U3;

[0015] One end of the capacitor CS3 is connected to the second pin of the multiplexer U3;

[0016] One end of capacitor CS4 is connected to pin 1 of multiplexer U3;

[0017] One end of capacitor CS5 is connected to pin 15 of multiplexer U3;

[0018] One end of capacitor CS6 is connected to pin 14 of multiplexer U3;

[0019] One end of capacitor CS7 is connected to pin 13 of multiplexer U3;

[0020] One end of capacitor CS8 is connected to pin 12 of multiplexer U3;

[0021] And the other ends of capacitors CS1, CS2, CS3, CS4, CS5, CS6, CS7, and capacitor CS8 are connected.

[0022] In one embodiment of the present invention, the operational amplifier module (220) includes an operational amplifier U5;

[0023] The inverting input terminal of the operational amplifier U5 is connected to the third pin of the multiplexer U3, and the output terminal of the operational amplifier U5 is connected to the 12th pin of the multiplexer U3.

[0024] In one embodiment of the present invention, the operational amplifier module (220) further includes resistors R15, R16, capacitors C11 and C13;

[0025] One end of the resistor R15 is connected to the inverting input end of the operational amplifier U5, and the other end is connected to the feedback port of the actual signal value output by the ultrasonic transducer;

[0026] One end of the resistor R16 is connected to the in-phase input terminal of the operational amplifier U5, and the other end is connected to the port for setting the signal value output by the ultrasonic transducer;

[0027] After the positive power supply terminal of the operational amplifier U5 is connected to the power supply, it is also connected to the capacitor C11, and the capacitor C11 is also grounded;

[0028] One end of the capacitor C13 is connected to the non-inverting input terminal of the operational amplifier U5, and the other end is grounded.

[0029] In one embodiment of the present invention, the three ports A, B and C of the multiplexer U3 are all connected to the single-chip microcomputer MCU.

[0030] The present invention also provides a method for regulating a circuit board for regulating ultrasonic output current stabilization time, comprising:

[0031] Adjust the levels of the three ports A, B, and C of the multiplexer U3 to open eight different paths respectively, forming a multi-channel analog switch;

[0032] The eight different paths are connected to capacitors of different sizes. By selecting the corresponding path, the corresponding capacitor can be connected to the circuit of the multiplexer U3.

[0033] After the capacitor is connected to the circuit of the multiplexer U3, it forms an integral operation circuit with the operational amplifier module (220) to perform integral compensation control of current feedback;

[0034] When the connected capacitors are of different sizes, the integral compensation makes the actual signal value output by the ultrasonic transducer equal to the set signal value output by the ultrasonic transducer, and the time required is also different, so that the circuit output has different stabilization times.

[0035] The present invention also provides an ultrasonic output current stabilization time control circuit board, comprising the ultrasonic output current stabilization time control circuit board, and also comprising a single-chip microcomputer MCU, a DAC module (420) and a constant voltage and constant current switching module (300); the single-chip microcomputer MCU is connected to the DAC module (420); the output end of the DAC module (420) and the output end of the constant voltage and constant current switching module (300) are connected to the input end of the ultrasonic output current stabilization time control circuit board.

[0036] In one embodiment of the present invention, a constant voltage and constant current switching module (300) comprises an analog switch (310), an AC-DC converter module and an integral operation circuit module; depending on the product in which the analog switch (310) is used, the connection relationship between the analog switch (310), the AC-DC converter module and the integral operation circuit module is different, and the number of the AC-DC converter modules and the integral operation circuit modules is also different.

[0037] In one embodiment of the present invention, when the analog switch (310) is an analog single-pole double-throw switch, and the analog single-pole double-throw switch is located at the end of the constant voltage and constant current switching module (300):

[0038] The AC-DC module comprises a first AC-DC module (321) and a second AC-DC module (322) having the same structure; the integral operation circuit module comprises a first integral operation circuit module (331) and a second integral operation circuit module (332) having the same structure;

[0039] The current feedback output by the ultrasonic transducer is connected in sequence to the first AC-DC conversion module (321) and the first integral operation circuit module (331) to form a constant current branch;

[0040] The voltage feedback output by the ultrasonic transducer is connected in sequence to the second AC-DC conversion module (322) and the second integral operation circuit module (332) to form a constant voltage branch;

[0041] The outputs of the constant voltage branch and the constant current branch are connected to the input end of the simulated single-pole double-throw switch, and the output end of the simulated single-pole double-throw switch is connected to the input end of the ultrasonic output current stabilization time control circuit board.

[0042] In one embodiment of the present invention, the A1 port of the simulated single-pole double-throw switch is connected to the output end of the constant current branch; the A2 port of the simulated single-pole double-throw switch is connected to the output end of the constant voltage branch; the ENB port of the simulated single-pole double-throw switch is connected to the single-chip microcomputer MCU;

[0043] Simulate the B port output selection signal of a single-pole double-throw switch;

[0044] The single-chip microcomputer MCU sends a control signal to select the A1 port or the A2 port of the simulated single-pole double-throw switch to connect to the B port of the simulated single-pole double-throw switch.

[0045] In one embodiment of the present invention, when the analog switch (310) is an analog dual-channel single-pole double-throw switch:

[0046] The input end of the analog dual-channel single-pole double-throw switch is respectively connected to the current feedback and voltage feedback output by the ultrasonic transducer; the output end of the analog dual-channel single-pole double-throw switch is connected to the AC-to-DC module and the integral operation circuit module in sequence; the output end of the integral operation circuit module is connected to the input end of the ultrasonic output current stabilization time control circuit board.

[0047] In one embodiment of the present invention, the output end of the voltage feedback output by the ultrasonic transducer is respectively connected to the NO1 port and the CN2 port of the analog dual-way single-pole double-throw switch; the output end of the current feedback output by the ultrasonic transducer is respectively connected to the NC1 port and the NO2 port of the analog dual-way single-pole double-throw switch;

[0048] And the COM2 port of the simulated dual-channel single-pole double-throw switch is connected to the AC-to-DC module; the single-chip microcomputer MCU is connected to the IN1 port and the IN02 port of the simulated dual-channel single-pole double-throw switch; the COM2 port of the simulated dual-channel single-pole double-throw switch outputs a selection signal, and the single-chip microcomputer MCU controls the voltage feedback or current feedback to be connected to the COM2 port of the simulated dual-channel single-pole double-throw switch.

[0049] In one embodiment of the present invention, when the analog switch (310) is an analog single-pole double-throw switch, and the analog single-pole double-throw switch is located at the head end of the constant voltage and constant current switching module (300):

[0050] The AC-to-DC module comprises a third AC-to-DC module (323) and a fourth AC-to-DC module (324) having the same structure;

[0051] The current feedback output by the ultrasonic transducer is connected to the third AC-DC conversion module (323) and then connected to the input end of the analog single-pole double-throw switch;

[0052] The voltage feedback output by the ultrasonic transducer is connected to the fourth AC-DC module (324) and then connected to the input end of the analog single-pole double-throw switch;

[0053] The output end of the analog single-pole double-throw switch is connected to the integral operation circuit module, and the output end of the integral operation circuit module is connected to the input end of the ultrasonic output current stabilization time control circuit board.

[0054] In one embodiment of the present invention, the A1 port of the simulated single-pole double-throw switch is connected to the current feedback output by the ultrasonic transducer; the A2 port of the simulated single-pole double-throw switch is connected to the voltage feedback output by the ultrasonic transducer; the single-chip microcomputer MCU is connected to the ENB port of the simulated single-pole double-throw switch; the B port of the simulated single-pole double-throw switch outputs a selection signal; the single-chip microcomputer MCU sends a control signal to select the A1 port or the A2 port of the simulated single-pole double-throw switch to connect to the B port of the simulated single-pole double-throw switch.

[0055] Compared with the prior art, the present invention has the following beneficial effects:

[0056] Current stabilization time control circuit:

[0057] The control of the current rise time is realized, and the current rise time can be controlled by the device settings. It can be controlled in multiple gears, and at least 8 gears can be set for control. The output effect corresponding to the gear is stable: the value of the same gear always remains stable, and will not change with use, affecting the consistency of the solder joints. Low hardware complexity: only one multiplexer and a few capacitors need to be added to realize the function, and it takes up little space and has little impact on other layouts of the ultrasonic drive circuit. Low cost: The additional cost of a single board is less than 1 yuan / PCS, which is suitable for mass production. Different gears can be selected according to the type of material to be welded to obtain better ultrasonic welding effects. Compared with switching devices such as relays, the multiplexer circuit used has the characteristics of multi-channel, easy control, low power consumption, and fast response.

[0058] Parameter calibration:

[0059] The current calibration is realized, and the current output of each circuit board is consistent. In the constant current mode, the welding effect is stable and the solder joints are consistent. The voltage calibration is realized, and the voltage output of each circuit board is consistent. In the constant voltage mode, the welding effect is stable and the solder joints are consistent. The impedance calibration is realized to maintain the consistency of the transducer impedance measurement.

[0060] The hardware complexity is low, the operation is simple and easy to use, and few peripherals are required. Current calibration only requires an oscilloscope, and voltage and impedance only require a 10-ohm standard resistor to complete the calibration. The calibrated parameter values ​​are fixed and saved in the memory storage chip. Only one calibration is required, and it can be used normally thereafter.

[0061] Constant voltage and constant current switching circuit:

[0062] The switching of two welding output functions, constant current and constant voltage, can be realized, and two functions, constant current frequency sweep and constant voltage frequency sweep, can be realized. The hardware does not need to use devices such as dial switches and relays, and the corresponding functions can be selected through software. Conventional software control: there is a delay. After waiting for the feedback data to be collected, the software adjusts the parameters, and then continues to collect feedback data, and repeats over and over again. The software setting of the present invention: there is no delay, and the constant current or constant voltage is set in advance, and the software does not need to calculate when working. Low hardware complexity: only one multiplexer and several capacitors need to be added to realize the function, and the space occupied is small, and the impact on other layouts of the ultrasonic drive circuit is small. Low cost: the cost of a single board is less than 1 yuan / PCS, which is suitable for mass production. Constant voltage or constant current function can be selected according to the type of material to be welded to obtain better ultrasonic welding effect. Using an analog switch instead of a relay can avoid the instantaneous signal jitter of the relay switch, and at the same time avoid the heating and unreliable hidden dangers of the relay being kept closed for a long time, and at the same time greatly reduce the delay time of switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 The present invention is a schematic diagram of a circuit board for regulating the stabilization time of ultrasonic output current according to an embodiment of the present invention.

[0064] Figure 2 The figure is a specific circuit diagram of a current stabilization time control circuit board according to an embodiment of the present invention.

[0065] Figure 3 Schematic diagram of the adjustment principle of an embodiment of the present invention.

[0066] Figure 4 FIG. 4 is a schematic diagram of a multiplexer according to an embodiment of the present invention.

[0067] Figure 5 FIG. 4 is a schematic diagram of part of the control codes of the multiplexer according to an embodiment of the present invention.

[0068] Figure 6 FIG. 4 is a schematic diagram of a driving circuit according to an embodiment of the present invention.

[0069] Figure 7 FIG. 4 is a schematic diagram of a memory storage chip according to an embodiment of the present invention.

[0070] Figure 8 Schematic diagram of a parameter calibration device according to an embodiment of the present invention.

[0071] Fig. 9 Schematic diagram of a sampling module according to an embodiment of the present invention.

[0072] Fig.10 Schematic diagram of an AC-to-DC amplifying module and a filtering module according to an embodiment of the present invention.

[0073] Fig.11 Schematic diagram of a bonding machine calibration system according to an embodiment of the present invention.

[0074] Fig.12 Schematic diagram of output current measured before calibration of the ultrasonic transducer according to an embodiment of the present invention.

[0075] Fig.13 Schematic diagram of the output current measured after calibration of the ultrasonic transducer according to an embodiment of the present invention.

[0076] Fig.14 Schematic diagram of an AC to DC module according to an embodiment of the present invention.

[0077] Fig.15 Schematic diagram of an integral operation circuit module according to an embodiment of the present invention.

[0078] Fig.16 The analog switch of the embodiment of the present invention is a schematic diagram of an analog single-pole double-throw switch.

[0079] Fig.17 Schematic diagram of a simulated single-pole double-throw switch according to an embodiment of the present invention.

[0080] Fig.18 The analog switch of the embodiment of the present invention is a schematic diagram of an analog dual-channel single-pole double-throw switch.

[0081] Fig.19 Schematic diagram of a simulated dual-channel single-pole double-throw switch according to an embodiment of the present invention.

[0082] Fig. 20 The analog switch of another embodiment of the present invention is a schematic diagram of an analog single-pole double-throw switch.

[0083] Fig.21 Schematic diagram of control connection of a simulated single-pole double-throw switch according to an embodiment of the present invention.

[0084] Fig. 22 Schematic diagram of a radio frequency amplifier module according to an embodiment of the present invention. DETAILED DESCRIPTION

[0085] In order to facilitate those skilled in the art to understand the technical solution of the present invention, the technical solution of the present invention is further described in conjunction with the accompanying drawings of the specification.

[0086] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0087] Example 1

[0088] See also Figure 2 As shown, the present invention provides an ultrasonic output current stabilization time control circuit board, including a multiplexing module 210 and an operational amplifier module 220.

[0089] In one embodiment of the present invention, the multiplexing module 210 includes a multiplexer U3 and a plurality of capacitors, and the capacitances of the plurality of capacitors gradually increase.

[0090] The plurality of capacitors include capacitors CS1, CS2, CS3, CS4, CS5, CS6, CS7 and capacitor CS8. One end of capacitor CS1 is connected to the 5th pin of multiplexer U3, one end of capacitor CS2 is connected to the 4th pin of multiplexer U3, one end of capacitor CS3 is connected to the 2nd pin of multiplexer U3, one end of capacitor CS4 is connected to the 1st pin of multiplexer U3, one end of capacitor CS5 is connected to the 15th pin of multiplexer U3, one end of capacitor CS6 is connected to the 14th pin of multiplexer U3, one end of capacitor CS7 is connected to the 13th pin of multiplexer U3, one end of capacitor CS8 is connected to the 12th pin of multiplexer U3, and the other ends of capacitors CS1, CS2, CS3, CS4, CS5, CS6, CS7 and capacitor CS8 are connected.

[0091] In one embodiment of the present invention, the multiplexing module 210 further includes a resistor RX1, one end of which is connected to the 16th pin of the multiplexer U3, and the other end of which is connected to the power supply. The resistor RX1 is used to limit the power input of the multiplexer U3.

[0092] In one embodiment of the present invention, the INH port, VEE port and VSS port of the multiplexer U3 are grounded, and the three ports A, B and C of the multiplexer U3 are connected to the single-chip microcomputer MCU, specifically to the GPIO ports PD4, PD5 and PD6 of the single-chip microcomputer. Specifically, the model of the multiplexer U3 is CD4051BNM96.

[0093] In one embodiment of the present invention, the operational amplifier module 220 is used to form an integral operation circuit to implement integral compensation in feedback control. Specifically, the operational amplifier module 220 includes an operational amplifier U5, resistors R15, R16, and capacitors C11 and C13.

[0094] In this embodiment, the inverting input terminal of the operational amplifier U5 is connected to the third pin of the multiplexer U3, and the output terminal of the operational amplifier U5 is connected to the twelfth pin of the multiplexer U3.

[0095] One end of the resistor R15 is connected to the inverting input end of the operational amplifier U5, and the other end is connected to the feedback port of the actual signal value output by the ultrasonic transducer. Figure 7 As shown, in another embodiment, the output end of the constant voltage and constant current switching module 200 is connected to the other end of the resistor R15. The ultrasonic transducer 10 is switched to constant current output or constant voltage output. After switching, the actual signal value output by the ultrasonic transducer 10, that is, the actual signal value is a current signal or a voltage signal, is output to the operational amplifier U5.

[0096] One end of the resistor R16 is connected to the non-inverting input end of the operational amplifier U5, and the other end is connected to the port for setting the signal value output by the ultrasonic transducer. Figure 7 As shown, in another embodiment, the DAC module 420 sets the setting signal value of the ultrasonic transducer output. And, if the constant voltage and constant current switching module 200 switches the ultrasonic transducer 10 to constant voltage output, the setting signal value of the DAC module 420 is a voltage value, and the constant voltage and constant current switching module 200 switches the ultrasonic transducer 10 to constant current output, then the setting signal value of the DAC module 420 is a current value. For example, the DAC module 420 can convert a digital signal into a voltage signal. For example, if you want a voltage of 200mV now, let the microcontroller MCU send a digital signal to the DAC module 420, and the data contains 200mV of data. After receiving the data, the DAC chip will output 200mV.

[0097] After the positive power supply terminal of the operational amplifier U5 is connected to the power supply, it is also connected to the capacitor C11, and the capacitor C11 is also grounded. One end of the capacitor C13 is connected to the non-inverting input terminal of the operational amplifier U5, and the other end is grounded.

[0098] In this embodiment, the ultrasonic transducer output can be a constant current output or a constant voltage output, so the actual signal value of the ultrasonic transducer output described here can be a current or a voltage. The set signal value output by the ultrasonic transducer can also be a set current setting value or a set voltage setting value.

[0099] When the actual signal value output by the ultrasonic transducer is not equal to the set signal value output by the ultrasonic transducer, the integration circuit adjusts the output voltage or current so that the ultrasonic transducer outputs current until the actual signal value output by the ultrasonic transducer is equal to the set signal value output by the ultrasonic transducer, thereby achieving the effect of controlling the current value.

[0100] See also Figures 3 to 5 As shown, in one embodiment of the present invention, the control principle is: the integral operation circuit plays a regulating role mainly by relying on the capacitor C, see Figure 3 As shown. Different circuits can be selected through the multiplexer U3, thereby selecting different capacitors to access the circuit. Figure 4 shown.

[0101] Multiplexer U3 is a digitally controlled analog switch with low ON impedance and very low OFF leakage current. It has three binary inputs, A, B, and C, and an INH control terminal. The three binary signals select 1 of the 8 channels to be turned on and connect one of the 8 inputs to the output. A partial program code example is shown below. Figure 5 shown.

[0102] Brief description of the code driving principle: The communication signal is sent by the host computer, such as the microcontroller MCU, which is divided into three signals A, B, and C after analysis, and then output by 3 GPIOs.

[0103] See also Figures 1 to 5 As shown, the present invention also provides a method for regulating a circuit board for regulating the stable time of ultrasonic output current, comprising:

[0104] The single-chip microcomputer MCU controls the levels of the three ports A, B, and C of the multiplexer U3, which can open eight different paths respectively to form a multi-channel analog switch.

[0105] The 8 paths are connected to capacitors of different sizes respectively. The capacitor can be connected to the circuit by selecting the corresponding path.

[0106] After the capacitor is connected to the circuit, it forms an integral operation circuit with the operational amplifier module 220 to perform integral compensation control in current feedback. When the size of the connected capacitor is different, the integral compensation makes the actual signal value output by the ultrasonic transducer equal to the set signal value output by the ultrasonic transducer, and the time required is also different, so that the circuit output has different stabilization time.

[0107] Example 2

[0108] There are errors in the consistency of electronic components themselves and the quality of welding. For example, there are certain deviations between the actual values ​​of resistors and capacitors and the standard values. These deviations will lead to inconsistent results such as voltage division and filtering. Since the signal has undergone multiple operational amplifications, the cumulative errors of each level of operational amplifiers will lead to different final output results. Since there are certain differences in the hardware of the driving circuit of each ultrasonic transducer, the voltage, current, impedance and other parameters measured by each ultrasonic driver board are different. In the related art, there is no unified calibration of the parameters of the ultrasonic driver board. Failure to calibrate will mainly cause the following effects:

[0109] 1. Under the same parameters, the output current value of each circuit board is different, which affects the welding effect;

[0110] 2. The impedance measured on each circuit board has certain differences, which affects the evaluation of the temperature rise performance of the transducer;

[0111] 3. If the voltage, current and impedance of each circuit board are different, the actual output voltage and current will be different in constant voltage, constant current and other modes, affecting the welding firmness and solder joint type under the preset parameters.

[0112] When the ultrasonic transducer is working, the impedance will change with the temperature; to ensure that each solder joint has good consistency, there are mainly two control methods: constant current and constant voltage.

[0113] Taking constant current as an example, the output process current remains stable, the envelope is straight, and each welding point maintains the same output current, thus achieving better consistency. In some other scenarios, maintaining a stable voltage is more effective than a stable current, and the constant voltage control mode is required.

[0114] The existing technology usually uses software to make adjustments by collecting the current voltage / current and comparing it with the set value. This adjustment method has several defects:

[0115] 1. There is a certain delay in software control, and when the welding load changes drastically, it cannot be adjusted and stabilized in time;

[0116] 2. The hardware circuit only supports one of constant voltage or constant current. During the power-on self-test, only one of constant voltage or constant current can be used for frequency sweep, which cannot meet the needs of multiple scenarios. For example, when the load impedance is large, constant voltage frequency sweep will result in very small current, which seriously affects the frequency sweep accuracy;

[0117] 3. Unable to switch between constant current and constant voltage modes.

[0118] In view of the above problems, the present invention also provides a driving circuit, including a single-chip microcomputer MCU, a DDS module 410, a DAC module 420, a current stabilization time adjustment module 200, a radio frequency amplifier module 430, a constant voltage and constant current switching module 300 and a memory storage chip U1. Among them, the current stabilization time adjustment module 200 is mainly an ultrasonic output current stabilization time control circuit board.

[0119] See also Figures 6 to 13 As shown, in one embodiment of the present invention, the memory storage chip U1 is connected to the single-chip microcomputer MCU for communication. The memory storage chip U1 has parameter calibration data written therein, and the parameter calibration data is used to calibrate the voltage, current and impedance of the ultrasonic drive circuit.

[0120] In this embodiment, a memory storage chip U1 with ferroelectric memory is used, and the memory storage chip U1 (FRAM) has the characteristic of not losing data after power failure. The calibrated data can be written into the memory storage chip U1 through I2C communication, and read after each power-on. Therefore, it is only necessary to calibrate once to obtain data, and there is no need to repeat the calibration later.

[0121] Since the internal data of the memory chip is generally "0xFF" when it leaves the factory, a judgment will be made each time it is read to ensure that the read value is accurate and to avoid misreading during the first use.

[0122] In the embodiment, the memory storage chip U1 is provided with resistors R4, RS1, and capacitor C5. The resistor R4 is connected to the SDA port of the memory storage chip U1, and the resistor RS1 is connected to the SCL port of the memory storage chip U1. The two ends of the capacitor C5 are respectively connected to the VCC port and the A0 port of the memory storage chip U1. And the communication port of the single-chip microcomputer MCU is respectively connected to the SDA port and the SCL port of the memory storage chip U1, and the parameter calibration data is written into the memory storage chip U1 through I2C communication.

[0123] The single-chip microcomputer MCU and the memory storage chip U1 communicate through the I2C protocol. The single-chip microcomputer MCU can perform data operations such as writing, erasing, and reading data on the memory storage chip U1. Resistors R4 and RS1 are pull-up resistors to ensure that the I2C communication line maintains a high-level pull-up state when no data is transmitted. Capacitor C5 is a filter capacitor to stabilize the power input of the memory storage chip U1 and reduce ripple interference.

[0124] In one embodiment of the present invention, parameter calibration data is obtained by a parameter calibration device. The parameter calibration device includes: a sampling module 110, an AC-to-DC amplification module 120, a filtering module 130, an ADC chip 140 and a standard resistor connected in sequence. Specifically, the ADC chip 140 is MAX1300.

[0125] In this embodiment, the sampling module 110 includes a voltage sampling capacitor C1, a voltage dividing capacitor C4, a voltage signal transformer T1, a current signal transformer T2, and a resistor R9.

[0126] The voltage sampling capacitor C1 and the voltage dividing capacitor C4 are connected in series, and the two ends of the series branch of the voltage sampling capacitor C1 and the voltage dividing capacitor C4 are provided with a connection terminal d1 and a connection terminal d2. The voltage signal transformer T1 is connected in parallel with the voltage sampling capacitor C1, the current signal transformer T2 is connected in parallel with the resistor R9, and the resistor R9 is connected with the connection terminal d2.

[0127] The voltage signal transformer T1 senses and outputs the voltage across the voltage sampling capacitor C1, and the output signal is V_BACK. The current signal transformer T2 senses and outputs the voltage across the resistor R9, and the output signal is I_BACK. The transformer is essentially a small transformer, a voltage-type device, which can sense and output the voltage across the resistor R9 in a fixed ratio, such as 1:1. Here, the resistance value of resistor R9 is known. For example, the resistor R9 is 1Ω. In this way, if the induced voltage is 100mV, its current is 100mA. In this way, the voltage is obtained and the current is calculated. In addition, the output signal V_BACK and the output signal I_BACK are both AC signals.

[0128] The voltage sampling capacitor C1 and the voltage dividing capacitor C4 form a voltage dividing circuit to prevent all voltages from being applied to the voltage sampling capacitor C1, so that the voltage dividing capacitor C4 has a certain equivalent capacitive reactance to prevent excessive current from flowing through the voltage signal transformer T1. Resistor R9 is a sampling resistor with a relatively small resistance value, which does not affect normal operation.

[0129] In one embodiment of the present invention, the AC-to-DC amplification module 120 includes: an operational amplifier U2A, an operational amplifier U2B, resistors R1, R2, R3, R5, R6, R7, R10, R11, capacitors C2, C3, C6, and diodes D1 and D2.

[0130] The output port of the voltage signal transformer T1 or the output end of the current signal transformer T2 is connected in series with the resistor R6 and then connected to the inverting input end of the operational amplifier U2B. The resistor R10 is connected to the non-inverting input end of the operational amplifier U2B and then grounded. The cathode of the diode D1 is connected to the inverting input end of the operational amplifier U2B, and the anode is connected to the output end of the operational amplifier U2A.

[0131] After resistor R5 and resistor R7 are connected in parallel, one end is connected to the anode of diode D2, and the other end is connected to the inverting input terminal of operational amplifier U2B. The cathode of diode D2 is connected to the anode of diode D1, and one end of resistor R3 is connected to the inverting input terminal of operational amplifier U2B, and the other end is connected to the anode of diode D2.

[0132] After the resistor R2 and the capacitor C2 are connected in parallel, the two ends are respectively connected to the inverting input and output of the operational amplifier U2A; and the non-inverting input of the operational amplifier U2A is connected to the resistor R11 and then grounded.

[0133] One end of the resistor R1 is connected to the output port of the voltage signal transformer T1 or the output end of the current signal transformer T2, and the other end is connected to the resistor R2.

[0134] The power supply terminal of the operational amplifier U2A is connected to the power supply, and the positive power supply terminal of the operational amplifier U2A is also connected to the capacitor C3 and then grounded. Also, the negative power supply terminal of the operational amplifier U2B is also connected to the capacitor C6 and then grounded.

[0135] In one embodiment of the present invention, the filter module 130 includes a resistor R8 and a capacitor C7. One end of the resistor R8 is connected to the output end of the operational amplifier U2B, and the other end is connected to the capacitor C3 and the ADC chip 140. The capacitor C3 is also grounded.

[0136] In this embodiment, the data measured by the ADC chip 140 is sent to the single-chip microcomputer MCU, so that the single-chip microcomputer MCU knows the actual value of the current measured data, specifically MAX1600.

[0137] In one embodiment of the present invention, the calibration method of the parameter calibration device includes a voltage calibration method, a current calibration method and an impedance calibration method. After the signal output by the transformer passes through the AC to DC circuit composed of an operational amplifier, the high-frequency interference is filtered out by an RC filter, and the output is a DC voltage OUT_AVERAGE. The ADC chip 140 performs voltage acquisition, and the following relationship can be obtained:

[0138] Y=kx+b, where x is the effective value output by the voltage signal transformer T1 and the current signal transformer T2, Y is the effective value of OUT_AVERAGE, k is a fixed conversion coefficient, and b is a fixed bias value, which is a constant.

[0139] Specifically, the voltage calibration method includes:

[0140] Set the initial model for voltage calibration: Y1=k1x1+b1.

[0141] The input port and output port of the ultrasonic transducer 10 are connected to the connection terminal d1 and the connection terminal d2 respectively, and connected to the AC power supply. The ultrasonic transducer 10 is an external output device, which is the ultrasonic source during ultrasonic welding, and the ultrasonic transducer 10 is driven by AC power. In this embodiment, there is no doubt that the ultrasonic transducer 10 has a built-in driving circuit.

[0142] First, when there is no current in the ultrasonic transducer 10, the output signal of the voltage signal transformer T1 is 0. The independent variable X1 in the voltage calibration initial model is 0. The value measured by the ADC chip 140 is the value of the constant b1 in the voltage calibration initial model.

[0143] Subsequently, the ultrasonic transducer 10 is removed, and the two ends of the standard resistor are connected to the terminal d1 and the terminal d2 respectively. According to the resistance value of the standard resistor and the set output current value of the ultrasonic transducer 10, the effective voltage value of the output end of the voltage signal transformer T1 is obtained. In this embodiment, for the convenience of calculation, the resistance value of the standard resistor is 1Ω, and the set output current value of the ultrasonic transducer 10 is 100mA. Specifically, the output current value of the ultrasonic transducer 10 is set by the bonding machine. The ultrasonic transducer 10 is set in the bonding machine. The bonding machine relies on the transducer vibration of the ultrasonic transducer 10 to perform ultrasonic bonding of the gold wire. Therefore, the output current of the bonding machine is actually the output current of the output current of the ultrasonic transducer 10.

[0144] The output signal of the voltage signal transformer T1 is converted into DC power by the AC-DC amplifier module 120, and after amplification, it is filtered by the filter module 130, and the ADC chip 140 is a sampling chip to measure the actual voltage value. The ratio of the actual voltage value and the effective voltage value measured by the ADC chip 140 is used as the fixed conversion coefficient K1 of the initial model of voltage calibration. In this embodiment, since the standard resistor has no equivalent capacitance and inductance, its voltage must be equal to 10Ω*100mA=1V, that is, the effective value of V_BACK, and then the value of OUT_AVERAGE at this time is measured, and the fixed conversion coefficient K1 can be calculated.

[0145] Finally, the obtained fixed conversion coefficient K1 and constant b1 are brought into the initial voltage calibration model to obtain the optimal voltage calibration model.

[0146] In one embodiment of the present invention, the current calibration method includes:

[0147] Set the initial model for current calibration: Y2=k2x2+b2.

[0148] The input port and the output port of the ultrasonic transducer 10 are respectively connected to the connection terminal d1 and the connection terminal d2, and connected to an AC power source.

[0149] First, when there is no current in the ultrasonic transducer 10, the output signal of the current signal transformer T2 is 0. The independent variable X2 in the current calibration initial model is 0. The value measured by the ADC chip 140 is the value of the constant b2 in the current calibration initial model;

[0150] Then, the ultrasonic transducer 10 is removed, and the two ends of the standard resistor are connected to the terminal d1 and the terminal d2 respectively; according to the resistance value of the standard resistor and the set output current value of the ultrasonic transducer 10, the effective current value of the output end of the current signal transformer T2 is obtained.

[0151] The output signal of the current signal transformer T2 is converted into DC power by the AC to DC amplifier module 120, and then amplified, and then filtered by the filter module 130, and the ADC chip 140 measures the actual current value.

[0152] The ratio of the actual current value and the effective current value measured by the ADC chip 140 is used as the fixed conversion coefficient K2 of the current calibration initial model.

[0153] Finally, the obtained fixed conversion coefficient K2 and constant b2 are brought into the initial current calibration model to obtain the optimal current calibration model.

[0154] In one embodiment of the present invention, after the voltage and current are calibrated, the ultrasonic transducer 10 is driven to output, and the impedance of the ultrasonic transducer 10 is obtained by dividing the collected voltage value by the current value. Specifically, the impedance calibration method includes:

[0155] After obtaining the optimal voltage calibration model and the optimal current calibration model;

[0156] The ultrasonic transducer 10 is connected to the wiring terminal d1 and the wiring terminal d2 to drive the ultrasonic transducer 10 to output, and the AC-DC amplification module 120 is respectively connected to the output port of the voltage signal transformer T1 or the output end of the current signal transformer T2. The voltage value measured by the ADC chip 140 is brought into the optimal voltage calibration model to obtain the calibration voltage. The current value measured by the ADC chip 140 is brought into the optimal current calibration model to obtain the calibration current.

[0157] The calibration impedance is obtained according to the calibration voltage and the calibration current.

[0158] The present invention also provides an embodiment. In the above embodiment, a set of sampling modules 110 is used to simultaneously collect voltage and current, and then an AC-to-DC amplification module 120, a filter module 130, an ADC chip 140 and a standard resistor are used to calibrate the voltage, current and impedance. However, the method for calibrating the current is relatively inconvenient. In the above embodiment, it has been explained that the ultrasonic transducer 10 is mounted in the bonding machine, and a calibration system is set in the bonding machine system, see the attached Fig.11 Therefore, in combination with an oscilloscope, the present invention also provides a method for calibrating current, which measures the actual current through an oscilloscope, observes the actual value, and then manually inputs it into the calibration system for compensation. Specifically, the method for calibrating current includes:

[0159] The ultrasonic transducer 10 is connected to an AC power source.

[0160] The current probe of the oscilloscope is clamped on the circuit of the ultrasonic transducer 10, and a calibration current value is set, and the calibration current value is output as the output current value of the ultrasonic transducer 10, and the oscilloscope measures the current at this time as the actual current value. At this time, the calibration current value is set by the bonding machine, and the calibration current value is specifically 60mA, which is the calibration-specific current size.

[0161] Using a bonding machine system equipped with the ultrasonic transducer 10 , the actual current value is input into a calibration system of the bonding machine system to perform current calibration.

[0162] The calibration system sends the actual current value to the driving circuit board of the ultrasonic transducer 10. After receiving the data, the driving circuit board of the ultrasonic transducer 10 performs "more reduction and less supplement" to make it equal to the calibration current value. In this embodiment, "more reduction and less supplement" means that if the current is greater than 60mA, some current is subtracted accordingly, and if the current is less than 60mA, a little current is added to make the current value close to 60mA.

[0163] See also Figures 7 to 13 As shown, in one embodiment of the present invention, the parameter calibration device utilizes the transformer principle of the mutual inductor to sense the voltage and current when the ultrasonic transducer is working; the sensed signal is an AC signal, which needs to be converted into a DC signal through an operational amplifier circuit, and then filtered through an RC filter and input into the ADC acquisition chip.

[0164] The voltage / current value of the ultrasonic transducer is in a fixed ratio to the value output by the transformer. The ratio of the transformer output value to the DC signal is also fixed. Therefore, the actual voltage / current value of the transducer can be calculated based on the data obtained by the ADC chip 140.

[0165] During calibration, when the output is 0, the bias value of the initial model is measured; an external 10-ohm standard resistor is used instead of the transducer to allow the voltage and current to reach a fixed value, such as 1V, and the fixed conversion coefficients are calculated in turn.

[0166] The obtained calibration data is written into the memory storage chip U1 through the I2C protocol. The data will be read each time the power is turned on, and will not be lost, so there is no need to recalibrate.

[0167] See also Fig.12 and Fig.13 As shown, the output current of the ultrasonic transducer 10 is set to 60mA. Fig.12 The actual current measured before calibration is 59.13mA. Fig.13 The actual current measured after calibration is 59.96mA.

[0168] The current value here is the effective value of the actual work done by the alternating current (59.13mA, 59.96mA). The error between the actual current value and the set value is generally required to be within 0.5mA. In this way, when each circuit board is set to the same value, the actual output current is close in size and has good consistency.

[0169] If it is not calibrated, the same setting value may result in some boards having large output values ​​and others having small output values, resulting in different solder joint sizes from different machines. It may even happen that two machines have the same settings, but one has too small output and the wire falls off, while the other has too large output and the wire is flattened.

[0170] See also Figure 6 As shown, in one embodiment of the present invention, the single-chip microcomputer MCU is connected to the DDS module 410 and the DAC module 420, and the output end of the DAC module 420 and the output end of the constant voltage and constant current switching module 300 are connected to the input end of the current stabilization time adjustment module 200. The output end of the DDS module 410 and the output end of the current stabilization time adjustment module 200 are connected to the input end of the RF amplifier module 430. Specifically, the model of the DDS module 410 is AD9833, and the DAC module 420 is SGM5348.

[0171] See also Figure 6 , Figures 14 to 22 As shown, in one embodiment of the present invention, the constant current and constant voltage switching module 300 includes an analog switch 310, an AC to DC module and an integral operation circuit module. According to different products using the analog switch 310, the connection relationship between the analog switch 310, the AC to DC module and the integral operation circuit module is different, and the number of the AC to DC module and the integral operation circuit module is also different.

[0172] In this embodiment, the AC-to-DC module includes an operational amplifier U11B, resistors R21, R22, R23, R24, R25, R28, and diodes D5 and D6.

[0173] One end of the resistor R24 ​​is connected to the inverting input terminal of the operational amplifier U11B, and the diodes D5 and D6 are connected in series and connected in parallel with the resistor R22, and the cathode of the diode D5 is connected to the inverting input terminal of the operational amplifier U11B. The resistors R23 and R24 are connected in parallel, and one end of the resistors R23 and R24 connected in parallel is connected to the anode of the diode D6, and the other end is connected to the resistor R21, and the resistor R21 is connected to the other end of the resistor R24, and one end of the resistor R28 is connected to the non-inverting input terminal of the operational amplifier U11B, and the other end is grounded.

[0174] In this embodiment, the integration operation circuit module includes an operational amplifier U6, resistors R17, R18, and capacitors CS9, C15, and C14.

[0175] Resistor R17 is connected to the inverting input terminal of the operational amplifier U6, resistor R18 is connected to the non-inverting input terminal of the operational amplifier U6, both ends of capacitor CS9 are connected to the inverting input terminal and output terminal of the operational amplifier U6 respectively, one end of capacitor C15 is connected to the non-inverting input terminal of the operational amplifier U6, and the other end is grounded, one end of capacitor C14 is connected to the positive power supply terminal of the operational amplifier U6, and the other end is grounded. Fig.15As shown, in this embodiment, in the integral operation circuit, the actual value of the feedback can be understood as the output current signal value or voltage value of the ultrasonic transducer 10. The setting value of the DAC output can be understood as the setting value output by the DAC module 420. And, when the "output current signal value or voltage value of the electric ultrasonic transducer 10" is not equal to the "setting value output by the DAC module 420", the integral operation circuit adjusts the output voltage / current, so that the electric ultrasonic transducer 10 outputs the voltage / current until the "output current signal value or voltage value of the electric ultrasonic transducer 10" is equal to the "setting value output by the DAC module 420", thereby achieving the effect of controlling the voltage / current value. In this embodiment, the adjustment is performed by capacitor CS9, but there is no gear for adjustment. In another embodiment of the present invention, the control voltage / current value can also be adjusted, and the current stabilization time adjustment module 200 is applied to achieve the gear adjustment of the current stabilization time.

[0176] In one embodiment of the present invention, see Fig.16 As shown, when the analog switch 310 is an analog single-pole double-throw switch, and the analog single-pole double-throw switch is located at the end of the switching circuit:

[0177] The AC-DC module includes a first AC-DC module 321 and a second AC-DC module 322 with the same structure, which can be understood as two AC-DC modules. The first AC-DC module 321 and the second AC-DC module 322 are defined only for the convenience of description. The integral operation circuit module includes a first integral operation circuit module 331 and a second integral operation circuit module 332 with the same structure, which can be understood as two integral operation circuit modules. The first integral operation circuit module 331 and the second integral operation circuit module 332 are defined only for the convenience of description.

[0178] The current feedback output by the ultrasonic transducer is connected to the first AC-to-DC module 321 and the first integral operation circuit module 331 in sequence to form a constant current branch.

[0179] The voltage feedback output by the ultrasonic transducer is connected to the second AC-DC converter module 322 and the second integral operation circuit module 332 in sequence to form a constant voltage branch.

[0180] The outputs of the constant voltage branch and the constant current branch are connected to an analog single-pole double-throw switch.

[0181] In one embodiment of the present invention, see Fig.17 As shown, the A1 port of the simulated single-pole double-throw switch is connected to the output end of the constant current branch, and the A2 port of the simulated single-pole double-throw switch is connected to the output end of the constant voltage branch.

[0182] The ENB port of the simulated single-pole double-throw switch is connected to the MCU, specifically, to the PA1 port of the GPIO port of the MCU, and the B port of the simulated single-pole double-throw switch outputs a selection signal. The MCU sends a control signal to select the A1 port or A2 port of the simulated single-pole double-throw switch to connect to the B port of the simulated single-pole double-throw switch. That is, when the MCU control signal Choose is a high-level logic 1, the current signal STATIC_I is selected to be connected to the B pin output to achieve constant current control. When the MCU control signal Choose is a low-level logic 0, the voltage signal STATIC_U is selected to be connected to the B pin output to achieve constant voltage control.

[0183] See Fig.18 As shown, in one embodiment of the present invention, when the analog switch 310 is an analog dual-channel single-pole double-throw switch:

[0184] The input end of the analog dual-channel single-pole double-throw switch is respectively connected to the current feedback and voltage feedback output by the ultrasonic transducer. The output end of the analog dual-channel single-pole double-throw switch is sequentially connected to the AC-DC conversion module and the integral operation circuit module, and the output end of the integral operation circuit module is connected to the input end of the current stabilization time adjustment module 200.

[0185] See Fig.19 As shown, the output ends of the voltage feedback output of the ultrasonic transducer are respectively connected to the NO1 port and the CN2 port of the analog dual-channel single-pole double-throw switch, and the output ends of the current feedback output of the ultrasonic transducer are respectively connected to the NC1 port and the NO2 port of the analog dual-channel single-pole double-throw switch.

[0186] The COM2 port of the simulated dual-channel single-pole double-throw switch is connected to the AC-DC module, and the single-chip microcomputer MCU is connected to the IN1 port and IN02 port of the simulated dual-channel single-pole double-throw switch, specifically, connected to the PC1 port and PC2 port in the GPIO port of the single-chip microcomputer MCU. The COM2 port of the simulated dual-channel single-pole double-throw switch outputs a selection signal, and the single-chip microcomputer MCU controls the voltage feedback or current feedback to be connected to the COM2 port of the simulated dual-channel single-pole double-throw switch.

[0187] The internal analog single-pole double-throw switch is controlled by the IN1 port and the IN2 port to determine two states: connecting the voltage feedback to the output for constant voltage. Connecting the current feedback to the output for constant current. In addition, the voltage feedback output by the ultrasonic transducer is sensed by the voltage signal transformer T3, and the current feedback output by the ultrasonic transducer is sensed by the current signal transformer T4.

[0188] In one embodiment of the present invention, see Fig. 20 and Fig.21As shown, when the analog switch 310 is an analog single-pole double-throw switch, and the analog single-pole double-throw switch is located at the head end of the constant voltage and constant current switching module 300:

[0189] The AC-DC module includes a third AC-DC module 323 and a fourth AC-DC module 324 having the same structure.

[0190] The current feedback output by the ultrasonic transducer is connected to the third AC-DC conversion module 323 and then connected to the input end of the analog single-pole double-throw switch.

[0191] The voltage feedback output by the ultrasonic transducer is connected to the fourth AC-DC module 324 and then connected to the input end of the analog single-pole double-throw switch.

[0192] The output end of the analog single-pole double-throw switch is connected to the integral operation circuit module, and the output end of the integral operation circuit module is connected to the input end of the current stabilization time adjustment module 200 .

[0193] In this embodiment, the A1 port of the simulated single-pole double-throw switch is connected to the current feedback output by the ultrasonic transducer; the A2 port of the simulated single-pole double-throw switch is connected to the voltage feedback output by the ultrasonic transducer. The single-chip microcomputer MCU is connected to the ENB port of the simulated single-pole double-throw switch, and the B port of the simulated single-pole double-throw switch outputs a selection signal. The single-chip microcomputer MCU sends a control signal to select the A1 port or the A2 port of the simulated single-pole double-throw switch to connect to the B port of the simulated single-pole double-throw switch.

[0194] In this embodiment, the single chip microcomputer MCU selects a signal, selects STATIC_I or STATIC_U signal, connects to the integral operation circuit module, selects "STATIC_I" to realize the constant current function, and selects "STATIC_U" to realize the constant voltage function.

[0195] See also Fig. 22 As shown, in one embodiment of the present invention, the RF amplifier module 430 includes a RF amplifier U4, resistors R12, R13, R14, and capacitors C8, C9, C10, and C12.

[0196] After the output end of the DDS module is connected to the resistor R12, the resistor R12 is connected to the 3rd pin of the RF amplifier U4. The output end of the current stabilization time adjustment module 200 is connected to the 1st pin of the RF amplifier U4. One end of the resistor R13 is connected to the power supply, and the other end is connected to the 2nd pin of the RF amplifier U4. One end of the resistor R14 is connected to the 2nd pin of the RF amplifier U4, and the other end is grounded. After the capacitors C8 and C9 are connected in parallel, one end is connected to the 8th pin of the RF amplifier U4, and the other end is grounded. After the capacitors C10 and C12 are connected in parallel, one end is connected to the 6th pin of the RF amplifier U4, and the other end is grounded. And, the 5th pin and the 7th pin of the RF amplifier U4 are connected and then output, and connected to the ultrasonic transducer 10. Wherein. Between the RF amplifier module 430 and the ultrasonic transducer 10, for example, an operational amplifier and a power amplifier are sequentially arranged. The operational amplifier filters the output signal of the RF amplifier module 430, amplifies the current signal or the voltage signal, and then inputs it to the power amplifier. The power amplifier does not change the voltage or current, nor does it change the frequency, but improves the driving capability and transmits it to the ultrasonic transducer 10 for output.

[0197] In one embodiment of the present invention, the DDS module 410 generates a fixed frequency signal and communicates with the microcontroller MCU via SPI.

[0198] See also Figures 1 to 22 As shown, the present invention also provides a driving method of a driving circuit, comprising:

[0199] The single-chip microcomputer MCU is powered on and runs, and reads the parameter calibration digital data written in the memory storage chip U1. The DDS module 410, the DAC module 420, the current stabilization time adjustment module 200, the RF amplifier module 430, and the constant voltage and constant current switching module 300 are calibrated through the parameter calibration digital data.

[0200] After the calibration is completed, the single-chip microcomputer MCU sends instructions to the DDS module 410 and the DAC module 420; after the DDS module 410 and the DAC module 420 receive the signals, the DDS module 410 outputs an AC frequency signal, and the DAC module 420 outputs a setting signal.

[0201] When the constant voltage and constant current switching module 300 switches to output a voltage signal, the DAC module 420 outputs a setting signal as a DC voltage signal. When the constant voltage and constant current switching module 300 switches to output a current signal, the DAC module 420 outputs a setting signal as a current signal.

[0202] The current stabilization time adjustment module 200 regulates the output signal of the constant voltage and constant current switching module 300 and the output setting signal of the DAC module 420 to make the output signal of the constant voltage and constant current switching module 300 equal to the output setting signal of the DAC module 420 and output a stable voltage or current signal.

[0203] The stable voltage or current signal and the AC frequency signal serve as inputs to the RF amplifier module 430 , and the RF amplifier module 430 outputs both a controlled frequency and a controlled voltage or current AC signal to the ultrasonic transducer.

[0204] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention, and any reference numerals in the claims should not be regarded as limiting the claims involved.

[0205] The above-described embodiments merely represent implementation methods of the invention. The protection scope of the present invention is not limited to the above-described embodiments. For those skilled in the art, several modifications and improvements may be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A circuit board for regulating the stable time of ultrasonic output current, characterized in that: include: A multiplexing module (210) and an operational amplifier module (220); wherein the multiplexing module (210) comprises a multiplexer U3 and a plurality of capacitors; and the capacitance values ​​of the plurality of capacitors gradually increase; and the operational amplifier module (220) is connected to the multiplexer U3; Wherein, the plurality of capacitors include capacitors CS1, CS2, CS3, CS4, CS5, CS6, CS7 and capacitor CS8; One end of capacitor CS1 is connected to pin 5 of multiplexer U3; One end of capacitor CS2 is connected to the 4th pin of multiplexer U3; One end of the capacitor CS3 is connected to the second pin of the multiplexer U3; One end of capacitor CS4 is connected to pin 1 of multiplexer U3; One end of capacitor CS5 is connected to pin 15 of multiplexer U3; One end of capacitor CS6 is connected to pin 14 of multiplexer U3; One end of capacitor CS7 is connected to pin 13 of multiplexer U3; One end of capacitor CS8 is connected to pin 12 of multiplexer U3; And the other ends of capacitors CS1, CS2, CS3, CS4, CS5, CS6, CS7, and capacitor CS8 are connected.

2. The ultrasonic output current stabilization time control circuit board according to claim 1, characterized in that: The operational amplifier module (220) includes an operational amplifier U5; The inverting input terminal of the operational amplifier U5 is connected to the third pin of the multiplexer U3, and the output terminal of the operational amplifier U5 is connected to the 12th pin of the multiplexer U3.

3. The ultrasonic output current stabilization time control circuit board according to claim 2, characterized in that: The operational amplifier module (220) further includes resistors R15, R16, capacitors C11 and C13; One end of the resistor R15 is connected to the inverting input end of the operational amplifier U5, and the other end is connected to the feedback port of the actual signal value output by the ultrasonic transducer; One end of the resistor R16 is connected to the in-phase input terminal of the operational amplifier U5, and the other end is connected to the port for setting the signal value output by the ultrasonic transducer; After the positive power supply terminal of the operational amplifier U5 is connected to the power supply, it is also connected to the capacitor C11, and the capacitor C11 is also grounded; One end of the capacitor C13 is connected to the non-inverting input terminal of the operational amplifier U5, and the other end is grounded.

4. The ultrasonic output current stabilization time control circuit board according to claim 1, characterized in that: The three ports A, B and C of the multiplexer U3 are all connected to the microcontroller MCU.

5. A method for regulating a circuit board for regulating ultrasonic output current stabilization time according to any one of claims 1 to 4, characterized in that: include: Adjust the levels of the three ports A, B, and C of the multiplexer U3 to open eight different paths respectively, forming a multi-channel analog switch; The eight different paths are connected to capacitors of different sizes. By selecting the corresponding path, the corresponding capacitor can be connected to the circuit of the multiplexer U3. After the capacitor is connected to the circuit of the multiplexer U3, it forms an integral operation circuit with the operational amplifier module (220) to perform integral compensation control of current feedback; When the connected capacitors are of different sizes, the integral compensation makes the actual signal value output by the ultrasonic transducer equal to the set signal value output by the ultrasonic transducer, and the time required is also different, so that the circuit output has different stabilization times.

6. A driving circuit, characterized in that: The invention comprises the ultrasonic output current stabilization time control circuit board as described in any one of claims 1 to 4, and also comprises a single-chip microcomputer MCU, a DAC module (420) and a constant voltage and constant current switching module (300); the single-chip microcomputer MCU is connected to the DAC module (420); the output end of the DAC module (420) and the output end of the constant voltage and constant current switching module (300) are connected to the input end of the ultrasonic output current stabilization time control circuit board.

7. The driving circuit according to claim 6, characterized in that: The constant voltage and constant current switching module (300) comprises an analog switch (310), an AC-DC conversion module and an integral operation circuit module; depending on the product in which the analog switch (310) is used, the connection relationship between the analog switch (310), the AC-DC conversion module and the integral operation circuit module is different, and the number of the AC-DC conversion modules and the integral operation circuit modules is also different.

8. The driving circuit according to claim 7, characterized in that: When the analog switch (310) is an analog single-pole double-throw switch, and the analog single-pole double-throw switch is located at the end of the constant voltage and constant current switching module (300): The AC-DC module comprises a first AC-DC module (321) and a second AC-DC module (322) having the same structure; the integral operation circuit module comprises a first integral operation circuit module (331) and a second integral operation circuit module (332) having the same structure; The current feedback output by the ultrasonic transducer is connected in sequence to the first AC-to-DC module (321) and the first integral operation circuit module (331) to form a constant current branch; The voltage feedback output by the ultrasonic transducer is connected in sequence to the second AC-DC conversion module (322) and the second integral operation circuit module (332) to form a constant voltage branch; The outputs of the constant voltage branch and the constant current branch are connected to the input end of the simulated single-pole double-throw switch, and the output end of the simulated single-pole double-throw switch is connected to the input end of the ultrasonic output current stabilization time control circuit board.

9. The driving circuit according to claim 8, characterized in that: The A1 port of the simulated single-pole double-throw switch is connected to the output end of the constant current branch; the A2 port of the simulated single-pole double-throw switch is connected to the output end of the constant voltage branch; the ENB port of the simulated single-pole double-throw switch is connected to the single-chip microcomputer MCU; Simulate the B port output selection signal of a single-pole double-throw switch; The single-chip microcomputer MCU sends a control signal to select the A1 port or the A2 port of the simulated single-pole double-throw switch to connect to the B port of the simulated single-pole double-throw switch.

10. The driving circuit according to claim 7, characterized in that: When the analog switch (310) is an analog dual-channel single-pole double-throw switch: The input end of the analog dual-channel single-pole double-throw switch is respectively connected to the current feedback and voltage feedback output by the ultrasonic transducer; the output end of the analog dual-channel single-pole double-throw switch is connected to the AC-to-DC module and the integral operation circuit module in sequence; the output end of the integral operation circuit module is connected to the input end of the ultrasonic output current stabilization time control circuit board.

11. The driving circuit according to claim 10, characterized in that: The output ends of the voltage feedback output by the ultrasonic transducer are respectively connected to the NO1 port and the CN2 port of the analog dual-channel single-pole double-throw switch; the output ends of the current feedback output by the ultrasonic transducer are respectively connected to the NC1 port and the NO2 port of the analog dual-channel single-pole double-throw switch; And the COM2 port of the simulated dual-channel single-pole double-throw switch is connected to the AC-to-DC module; the single-chip microcomputer MCU is connected to the IN1 port and the IN02 port of the simulated dual-channel single-pole double-throw switch; the COM2 port of the simulated dual-channel single-pole double-throw switch outputs a selection signal, and the single-chip microcomputer MCU controls the voltage feedback or current feedback to be connected to the COM2 port of the simulated dual-channel single-pole double-throw switch.

12. The driving circuit according to claim 7, characterized in that: When the analog switch (310) is an analog single-pole double-throw switch, and the analog single-pole double-throw switch is located at the head end of the constant voltage and constant current switching module (300): The AC-to-DC module comprises a third AC-to-DC module (323) and a fourth AC-to-DC module (324) having the same structure; The current feedback output by the ultrasonic transducer is connected to the third AC-DC conversion module (323) and then connected to the input end of the analog single-pole double-throw switch; The voltage feedback output by the ultrasonic transducer is connected to the fourth AC-DC module (324) and then connected to the input end of the analog single-pole double-throw switch; The output end of the analog single-pole double-throw switch is connected to the integral operation circuit module, and the output end of the integral operation circuit module is connected to the input end of the ultrasonic output current stabilization time control circuit board.

13. The driving circuit according to claim 12, characterized in that: The A1 port of the simulated single-pole double-throw switch is connected to the current feedback output by the ultrasonic transducer; the A2 port of the simulated single-pole double-throw switch is connected to the voltage feedback output by the ultrasonic transducer; the single-chip microcomputer MCU is connected to the ENB port of the simulated single-pole double-throw switch; the B port of the simulated single-pole double-throw switch outputs a selection signal; the single-chip microcomputer MCU sends a control signal to select the A1 port or the A2 port of the simulated single-pole double-throw switch to be connected to the B port of the simulated single-pole double-throw switch.

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