CN104183531B - Lead wire clamping system - Google Patents

Abstract

The invention provides a lead wire clamping system, which includes a piezoelectric micro-gripper and a piezoelectric drive system. The piezoelectric drive system includes a microprocessor module, a D/A waveform generation module, a high-voltage operational amplifier module, a power Amplifying module, high-voltage bootstrap power supply module and power-on sequence control module. The lead wire clamping system of the invention is not susceptible to electromagnetic interference, is simple to assemble, and is not easy to burn the voice coil motor.

Description

Lead Clamping System

technical field

The invention relates to the field of semiconductor packaging, in particular to a lead clamping system.

Background technique

IC/LED wire bonding machine is used for welding LED, triode, and IC integrated circuit internal leads, and is an important equipment for semiconductor packaging production line. The lead wire gripper is the core part of the IC/LED wire bonding machine, and an electromagnetic micro gripper is generally used. One end of the electromagnetic micro-gripper is a fixed clamping arm, and the other end is driven by a voice coil motor. Its advantages are low control voltage, easy installation and fixed lead-in holes, and its disadvantages are susceptible to electromagnetic interference, complicated assembly, and It is easy to burn the voice coil motor when it is disturbed by external force.

Contents of the invention

The purpose of the present invention is to provide a lead wire clamping system, which is used to solve the problems that the existing lead wire clamper is susceptible to electromagnetic interference, complex in assembly and easy to burn out the voice coil motor.

In order to solve the above-mentioned technical problems, the present invention provides a lead clamping system, including a piezoelectric micro-gripper and a piezoelectric drive system, the piezoelectric drive system includes a microprocessor module, a D/A waveform generation module, A high-voltage operational amplifier module, a power amplification module, a high-voltage bootstrap power supply module and a power-on sequence control module, a D/A waveform generation module connected to the microprocessor module and a high-voltage operational amplifier module, and the high-voltage bootstrap power supply module and The power-on sequence control module, the high-voltage operational amplifier module and the power amplification module are all connected, the power amplification module is also connected with the high-voltage operational amplifier module and the piezoelectric micro-holder, and the microprocessor module is also connected with the upper The electrical timing control module is connected.

Preferably, the microprocessor module includes a microprocessor, a power-on indicator light, keys, a serial data bus and a JTAG emulation interface.

Preferably, the microprocessor module is a DSP microprocessor chip.

Preferably, the D/A waveform generation module includes an address planning inverter, an AND-OR gate circuit, a D/A waveform generation circuit, and an external trigger circuit for an IO port.

Preferably, the high-voltage operational amplifier module includes at least one high-voltage operational amplifier.

Preferably, the power amplification module includes a power amplification chip, an overcurrent protection element, and a bootstrap boost power circuit.

Preferably, the bootstrap boost power circuit has a complementary MOSFET group, and the complementary MOSFET group is arranged between the DC power supply and the capacitor.

Preferably, the high-voltage bootstrap power supply module includes a transformer, a switch tube, and a control chip.

Preferably, the power-on sequence control module includes a relay module and a drive module.

The lead clamping system of the present invention includes a piezoelectric micro-gripper and a piezoelectric drive system, and the piezoelectric drive system includes a microprocessor module, a D/A waveform generation module, a high-voltage operational amplifier module, a power amplifier module, a high-voltage automatic Lifting power supply module and power-on sequence control module are not susceptible to electromagnetic interference, easy to assemble, and not easy to burn out the voice coil motor.

Description of drawings

Fig. 1 is the schematic block diagram of lead clamping system of the present invention;

Fig. 2 is a schematic block diagram of the piezoelectric drive system in Fig. 1;

Fig. 3 is a schematic diagram of the power-on process of the lead clamping system of the present invention;

Fig. 4 is a schematic circuit diagram of a bootstrap boost power circuit of the high-voltage bootstrap voltage module in Fig. 2;

Fig. 5 is a schematic diagram of the comparison of output waveforms before and after the ZV time lag filter is introduced in the present invention.

detailed description

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Please refer to FIG. 1 , the present invention provides a wire clamping system, including a piezoelectric micro-gripper 100 and a piezoelectric driving system 200 . The piezoelectric micro-gripper 100 mainly relies on the piezoelectric ceramic stack material embedded in the flexible hinge to provide clamping force. The piezoelectric ceramic stack material mainly works on the principle of inverse piezoelectric effect. The size of the voltage, the piezoelectric micro-gripper expands and contracts in a corresponding scale, and the advantage of the piezoelectric material is that the driving voltage and the output distance present a linear relationship.

Please refer to FIG. 2, the piezoelectric drive system 200 includes a microprocessor module 210, a D/A waveform generation module 220, a high-voltage operational amplifier module 230, a power amplifier module 240, a high-voltage bootstrap power supply module 250 and a power-on sequence control module 260 .

The D/A waveform generation module 220 is connected to the microprocessor module 210 and the high-voltage op-amp module 230, the high-voltage bootstrap power supply module 250 and the power-on sequence control module 260, the high-voltage op-amp module 230 and the power amplifier module 240 are connected, the power amplification module 240 is also connected with the high-voltage operational amplifier module 230 and the piezoelectric micro-gripper 100 , and the microprocessor module 210 is also connected with the power-on sequence control module 260 .

The microprocessor module 210 includes a microprocessor, a power-on indicator light, keys, a serial data bus and a JTAG emulation interface.

The DSP microprocessor chip used in the microprocessor module is TMS320F2812PGFA, which has the advantages of high computing speed and strong real-time controllability. This chip is a mature control chip designed by TI in the field of industrial control, which is used to control the power-on sequence of the waveform generation chip DAC and relay. The embedded control algorithm constitutes the core of the piezoelectric drive system, and the CAN control bus and serial data bus chip are externally expanded, which can realize the bus control and serial communication control functions of the computer upper computer.

The DSP microprocessor chip only needs to be connected to a 30M crystal oscillator to provide a working clock. Due to the oscillating circuit and phase-locked loop inside the DSP microprocessor chip, the frequency multiplication coefficient of the PLL can be controlled by the PLLCR register, and can also be dynamically modified by the software in real time, so that the CPU can work at a working frequency of 150M, and its clock cycle is 6.67 ns, can provide faster work efficiency and extremely high computing speed. At the same time, it can embed the timer function and external register interface (XINTF) to write data periodically to the D/A input waveform of the digital-to-analog converter. It also has address and data peripheral functions, which can easily enable the peripheral D/A circuit to output stable waveforms. . It saves the planning of complex CPLD control peripheral circuit logic, reduces circuit cost, and has better usability. And it has two-way SCI serial port communication, which can realize the communication interface of RS232 and RS485, and can realize the compatibility of the data communication interface of industrial control.

The D/A waveform generation module 220 includes an address planning inverter, an AND-OR gate circuit, a D/A waveform generation circuit and an external trigger circuit for an IO port.

The high-voltage operational amplifier module 230 includes at least one high-voltage operational amplifier.

The power amplifier module 240 includes a power amplifier chip, an overcurrent protection element, and a bootstrap boost power circuit.

The high-voltage bootstrap power module 250 includes a transformer, a switch tube, and a control chip.

The power-on sequence control module 260 includes a relay module and a driver module.

The components of the piezoelectric drive system 200 require a high-voltage 220V DC switching power supply and a DC power supply for the control part, including control circuit levels of 12V, -12V, 5V, and 3.3V. Since the power supply conditions and power accuracy requirements of the components of the entire piezoelectric driving system 200 are different, a good power-on sequence and work efficiency are required. If the power-on sequence is wrong, the high-voltage circuit will form an instantaneous potential difference to the ground on the control part of the chip, which will easily damage the chip of the control circuit.

Please refer to FIG. 3 , the power-on method of the piezoelectric drive system 200 includes the following steps:

Step S1: system initialization, and the piezoelectric drive system 200 is powered on.

Step S2: supply power to the switching power supply, the high-voltage bootstrap power module 250 works, and starts charging.

Step S3: Supply 3.3V direct current to the peripheral equipment.

Step S4: supplying 1.8V direct current to the DSP microprocessor chip.

The power supply of the control circuit core TMS320F2812PGFA chip is 1.8V, and the power supply level of the peripheral equipment is 3.3V. First supply 3.3V to the peripheral equipment, and then supply 1.8V to the core circuit. The interval between them should not exceed 1ms, otherwise the chip will heat up. If the working time is too long, the life of the chip will be shortened and the chip will be burned. ,

Step S5: When the high-voltage bootstrap power supply module 250 is fully charged, if the voltage reaches 219V, send a charging completion signal to the DSP microprocessor chip.

Step S6: After the DSP microprocessor chip receives the charging completion signal, it sends out a driving signal.

Step S7: Control the isolation of the power amplifier module 240, the microprocessor module 210 and the relay module of the power-on sequence control module 260.

Step S8: The high-voltage operational amplifier module 230 and the power amplifier module 240 start working.

Step S9: Driving the piezoelectric micro-gripper 100 .

Such a good control of the power-on sequence enables good power-on control and avoids the interference of the high-voltage power supply on the control circuit.

Please refer to Figure 4. In order to better suppress the vibration amplitude of the system when it is on or off, the bootstrap boost power circuit uses a complementary MOSFET group output to enable the piezoelectric ceramics and flexible amplification to respond quickly, enabling The piezoelectric microgripper 100 opens and closes rapidly.

The bootstrap boost power circuit includes an operational amplifier U1, resistors R1-R3, a complementary MOSFET group, a capacitor C1 and two diodes D1-D2 that relatively clamp positive and negative 20V voltages.

The positive input terminal of the operational amplifier U1 is connected to the input voltage V-in, the negative input terminal is grounded through the resistor R1, and the output terminal is connected to the anode of the diode D1. The cathode of the diode D1 is connected to the cathode of the diode D2, and the anode of the diode D2 is connected to the negative input terminal of the operational amplifier U1 through the resistors R3 and R2 in turn. The intersection between the resistor R3 and the resistor R2 is grounded through the capacitor C1.

The complementary MOSFET group includes a set of N-channel HEXFET MOS transistors Q1 and a set of P-channel HEXFET MOS transistors Q2. The drain of the NMOS transistor Q1 is connected to the 5V DC power supply VDD, the source is connected to the drain of the PMOS transistor Q2, and the gate is connected to the gate of the PMOS transistor Q2. The source of the PMOS transistor Q2 is grounded.

The NMOS transistor Q1 is used to increase the output power; since the piezoelectric ceramic is equivalent to a capacitive load, the PMOS transistor Q2 is used for a fast discharge circuit.

The charging current provided by the NMOS tube Q1 in this circuit is I1, which improves the driving capability of the operational amplifier and makes the charging time of the piezoelectric ceramic faster; the PMOS tube Q2 provides a discharge circuit for the piezoelectric ceramic, and the discharge current is I2, so that the charging of the piezoelectric ceramic The charge can be released quickly. The charging and discharging speed of the piezoelectric ceramic is accelerated through the output of the complementary MOSFET group, so that the piezoelectric ceramic and the flexible amplifying mechanism can respond quickly, so that the piezoelectric micro-holder 100 can be quickly opened and closed. In this way, the dynamic response of the machine is improved, and at the same time, it can provide the basis for fast time response for the embedding of the input shaping algorithm in this paper, which can improve the power effect and make the charge of the piezoelectric ceramic be released quickly.

Adding clamping voltage diodes D1-D2 in the circuit enables the NMOS transistor Q1 and the PMOS transistor Q2 to be fully turned on.

In order to make the circuit more stable, the circuit can also realize the superposition of power through multiple sets of NMOS transistors and PMOS transistors, so that the output quick response is further improved.

The power boost and fast discharge structure can achieve power boost and discharge effects through complementary MOSFET groups, and the transient charge and discharge currents provided by the power supply to the piezoelectric ceramic actuator load can be accumulated in parallel. The ground, peak output current and peak output power can be doubled by using multiple sets of parallel power amplifier circuit control circuits, then the output power of the drive power supply can be obtained:

W=∫I(t)V(t)dt;

Therefore, adding a complementary MOSFET group can effectively increase the power of the power supply, and improve the charging efficiency, so that the charging time of the capacitor is greatly reduced, and a higher current can be provided. Adding a complementary MOSFET group, the power boost circuit can increase the response speed from the charging time of 1.96ms to 250us.

Please refer to FIG. 5 , the effect of the existing micro gripper in the open state when driven by a 20HZ square wave with a peak value of 120V is shown in curve C-o. The front-end sinusoidal attenuation oscillation is the vibration effect of the rising edge of the square wave. Due to the shaking of the rising edge of the driving waveform, the amplitude of the velocity vibration curve is relatively large. The edge is trembling, so the impact response is relatively large when it is closed, and the amplitude of its speed curve is large when it is closed, forming a large closing force, resulting in a lot of noise and serious jitter when it is working. This waveform is not suitable for analysis. The actual wiring process.

The present invention embeds a ZV time-lag filter on the rising edge of the output waveform, so that a faster response speed can be obtained at the rising time of charging, and the system has the best vibration suppression effect, so a suitable ZV time-lag filter is selected on the rising edge , and the overall waveform is in a stable output effect by adopting the form of trapezoidal wave drop when it is turned off. The output effect after shaping is shown in the curve C-n. It can be seen that the vibration amplitude of the system can be well suppressed at the same time in the open and closed state, so that the vibration time of the micro gripper vibration control system is reduced from 25ms to 700us, which greatly reduces the vibration energy of the system. The falling form of trapezoidal wave reduces the vibration energy of the system, and the maximum vibration velocity energy is reduced by 90%. Reduced the residual vibration of the gripper in the open and closed state.

The lead clamping system of the present invention adopts a piezoelectric micro-gripper 100 and a piezoelectric drive system 200, and the piezoelectric drive system 200 adopts a microprocessor module 210, a D/A waveform generation module 220, a high-voltage op-amp module 230, The power amplification module 240, the high-voltage bootstrap power supply module 250 and the power-on sequence control module 260 are not susceptible to electromagnetic interference, easy to assemble, and difficult to burn out the voice coil motor.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (9)

1. A lead clamping system, comprising a piezoelectric micro-gripper and a piezoelectric drive system, characterized in that the piezoelectric drive system comprises a microprocessor module, a D/A waveform generation module, a high-voltage operational amplifier module, a power amplification module, a high-voltage bootstrap power supply module, and a power-on sequence control module. The D/A waveform generation module is connected to the microprocessor module and the high-voltage op-amp module. The electrical sequence control module, the high-voltage operational amplifier module and the power amplification module are all connected, and the power amplification module is also connected with the high-voltage operational amplifier module and the piezoelectric micro-holder, and the microprocessor module is also connected with the power-on sequence control module. The modules are connected. 2. The wire clamping system according to claim 1, wherein the microprocessor module comprises a microprocessor, a power-on indicator light, buttons, a serial data bus and a JTAG emulation interface. 3. The wire clamping system according to claim 2, wherein the microprocessor module is a DSP microprocessor chip. 4. The wire clamping system according to claim 1, wherein the D/A waveform generation module includes an address planning inverter, an AND-OR gate circuit, a D/A waveform generation circuit and an external trigger circuit of the IO port . 5. The lead clamping system according to claim 1, wherein the high-voltage operational amplifier module comprises at least one high-voltage operational amplifier. 6. The wire clamping system according to claim 1, wherein the power amplifier module comprises a power amplifier chip, an overcurrent protection element, and a bootstrap boost power circuit. 7. The wire clamping system according to claim 6, wherein the bootstrap boost power circuit has a complementary MOSFET group, and the complementary MOSFET group is arranged between the DC power supply and the capacitor. 8. The wire clamping system according to claim 1, wherein the high-voltage bootstrap power module comprises a transformer, a switching tube, and a control chip. 9. The wire clamping system according to claim 1, wherein the power-on sequence control module comprises a relay module and a drive module.