CN212305191U

CN212305191U - Voice coil motor force control driving circuit

Info

Publication number: CN212305191U
Application number: CN202020573601.2U
Authority: CN
Inventors: 李天龙; 邹宇; 李思阳
Original assignee: Goal Technology Shenzhen Co ltd
Current assignee: Goal Technology Shenzhen Co ltd
Priority date: 2020-04-16
Filing date: 2020-04-16
Publication date: 2021-01-05
Anticipated expiration: 2030-04-16

Abstract

The utility model provides a voice coil motor force control driving circuit, which comprises a control module, a drive axle module, a power supply module, a current sampling module and a signal conditioning module; the drive axle module comprises an H axle drive unit and an H axle switch unit connected with the H axle drive unit, the control module outputs a PWM drive signal, and the H axle drive unit is used for amplifying the PWM drive signal; the power supply module provides a motor power supply for the voice coil motor through the H-bridge switch unit; the current sampling module comprises a current sampling unit, a filtering unit and a signal two-stage amplifying unit which are sequentially connected, the signal two-stage amplifying unit comprises an amplifier, the amplification factor of the amplifier to a current signal is more than or equal to 50 times, and the amplifier is connected with the control module; the signal conditioning module is connected with the control module and used for receiving motion information driven by the voice coil motor. Through the mode, the control module can accurately control the current of the voice coil motor, and the force control precision of the voice coil motor is improved.

Description

Voice coil motor force control driving circuit

Technical Field

The utility model relates to a motor drive technical field, more specifically say, relate to a voice coil motor power control drive circuit.

Background

The voice coil motor is used as an execution original which can be directly driven, and has the characteristics of simple structure, high-speed response and the like. Common driving methods for voice coil motors include linear driving and Pulse Width Modulation (PWM) driving. The linear driving control mode is simple, but the energy consumption is large, and the output efficiency is low; the PWM driving has low energy consumption, but the thrust of the output end of the PWM driving is jittered, the control precision of the force is low, and the dynamic performance of the voice coil motor is poor. In some devices with high force control requirements, such as automatic chip mounters, the traditional driving mode cannot meet the force control requirements, and therefore a force control driving circuit with higher precision is needed.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a voice coil motor power control drive circuit to solve the problem that traditional drive mode power control precision is low.

In order to achieve the above object, the utility model provides a voice coil motor force control driving circuit, which comprises a control module, a drive axle module, a power supply module, a current sampling module and a signal conditioning module; the drive axle module comprises an H-bridge drive unit and an H-bridge switch unit connected with the H-bridge drive unit, the control module outputs a PWM drive signal, and the H-bridge drive unit is used for amplifying the PWM drive signal; the power supply module provides a motor power supply for the voice coil motor through the H-bridge switch unit; the current sampling module comprises a current sampling unit, a filtering unit and a signal double-stage amplifying unit which are sequentially connected, the current sampling unit is used for collecting working current signals of the voice coil motor in real time, the signal double-stage amplifying unit comprises an amplifier, the amplification factor of the amplifier to the working current signals filtered by the filtering unit is greater than or equal to 50 times, and the amplifier is connected with the control module; the signal conditioning module is connected with the control module and used for receiving the motion information driven by the voice coil motor.

Preferably, the amplifier includes a first signal input end, a second signal input end, a first signal output end corresponding to the first signal input end and a second signal output end corresponding to the second signal input end, the first signal input end is connected to the filtering unit, the second signal input end is connected to the first signal output end, and the second signal output end is connected to the control module.

Preferably, the H-bridge driving unit includes a first driving chip and a second driving chip, the control module outputs a first complementary PWM driving signal and a second complementary PWM driving signal, the first driving chip is configured to amplify the first complementary PWM driving signal, and the second driving chip is configured to amplify the second complementary PWM driving signal.

Preferably, the H-bridge switch unit includes a first N-channel MOS transistor, a second N-channel MOS transistor, a third N-channel MOS transistor, and a fourth N-channel MOS transistor, a gate of the first N-channel MOS transistor is connected to the first output terminal of the first driver chip, a gate of the second N-channel MOS transistor is connected to the second output terminal of the first driver chip, the first N-channel MOS transistor and the second N-channel MOS transistor are connected in series between the power module and the ground, a common end of the first N-channel MOS transistor and the second N-channel MOS transistor is connected to one end of the voice coil motor, a gate of the third N-channel MOS transistor is connected to the first output terminal of the second driver chip, a gate of the fourth N-channel MOS transistor is connected to the second output terminal of the second driver chip, and the third N-channel MOS transistor and the fourth N-channel MOS transistor are connected in series between the power module and the ground, and the common end of the third N-channel MOS tube and the common end of the fourth N-channel MOS tube are connected with the other end of the voice coil motor.

Preferably, the current sampling unit includes a first sampling resistor and a second sampling resistor, the first sampling resistor is connected in series between the second N-channel MOS transistor and ground, and the second sampling resistor is connected in series between the fourth N-channel MOS transistor and ground.

Preferably, the filtering unit includes a first filtering circuit and a second filtering circuit; the first filter circuit comprises a first filter resistor, a first filter capacitor, a second filter resistor and the first sampling resistor which are sequentially connected to form an annular filter circuit; the second filter circuit comprises a third filter resistor, a second filter capacitor, a fourth filter resistor and a second sampling resistor which are sequentially connected to form an annular filter circuit.

Preferably, the current sampling module further includes a protection unit, the protection unit includes a first protection circuit and a second protection circuit, the first protection circuit is respectively connected to the amplifier and the control module, and the first protection circuit includes a first resistor, a second resistor, a first capacitor and a first switching diode unit; the second protection circuit is respectively connected with the amplifier and the control module, and comprises a third resistor, a fourth resistor, a second capacitor and a second switch diode unit.

Preferably, the control module includes a pulse width modulation unit, an analog-to-digital conversion unit and a pulse counting unit, the pulse width modulation unit outputs the PWM driving signal, the analog-to-digital conversion unit is connected to the current sampling module and the pulse width modulation unit, and the pulse counting unit is connected to the signal conditioning module and the pulse width modulation unit.

Preferably, the signal conditioning module includes a third filter circuit and a digital logic circuit.

Preferably, the voice coil motor force control driving circuit further comprises a display module and a function extension module, wherein the display module and the function extension module are connected with the control module, and the function extension module comprises a man-machine interaction and communication interface circuit.

Compared with the prior art, the utility model provides a voice coil motor power control drive circuit's current sampling module is including the current sampling unit, filtering unit and the signal doublestage amplification unit that connect gradually, current sampling unit is used for gathering in real time voice coil motor's operating current signal, the signal doublestage amplification unit includes the amplifier, the amplifier is to the warp the magnification of the operating current signal after the filtering unit filters is more than or equal to 50 times, the amplifier with control module connects. The amplifier is used for carrying out high-precision operational amplification on the collected working current signal (namely, the current sampling signal), so that the precision of the working current signal finally output to the control module is ensured, and the control module can accurately control the current of the voice coil motor, thereby realizing the output control of the voice coil motor and improving the force control precision of the voice coil motor.

Drawings

Fig. 1 is a block diagram of a power control driving circuit of a voice coil motor according to an embodiment of the present invention;

fig. 2 is a block diagram of a control module according to an embodiment of the present invention;

fig. 3 is a block diagram of a current sampling module according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a portion of a drive axle module according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of another portion of a drive axle module according to an embodiment of the present invention;

fig. 6 is a schematic diagram of a partial structure of a current sampling module according to an embodiment of the present invention;

fig. 7 is another structural block diagram of the voice coil motor force control driving circuit according to the embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1-6, an embodiment of the present invention provides a voice coil motor power control driving circuit 100, wherein the voice coil motor is connected to a mechanical system for driving the mechanical system to move, and a sensor for collecting motion information of the mechanical system is disposed on the mechanical system. The voice coil motor force control driving circuit 100 comprises a control module 1, a drive bridge module 2, a power supply module 3, a current sampling module 4 and a signal conditioning module 5.

Specifically, the drive axle module 2 includes an H-bridge drive unit 21 and an H-bridge switch unit 22. The input end of the H-bridge driving unit 21 is connected with the output end of the control module 1, and the output end of the H-bridge driving unit 21 is connected with the input end of the H-bridge switching unit 22. The control module 1 outputs a PWM driving signal, the H-bridge driving unit 21 is configured to amplify the PWM driving signal, and the amplified PWM driving signal is output to the H-bridge switching unit 22 to control on/off of the H-bridge switching unit 22. The power module 3 supplies motor power to the voice coil motor through the H-bridge switching unit 22. The current sampling module 4 includes a current sampling unit 41, a filtering unit 42, and a signal two-stage amplifying unit 43, which are connected in sequence. The current sampling unit 41 is configured to collect a working current signal (i.e., a current sampling signal) of the voice coil motor in real time, the filtering unit 42 is configured to filter the working current signal, and the signal dual-stage amplifying unit 43 is configured to amplify the filtered working current signal. The signal dual-stage amplifying unit 43 comprises an amplifier U3, and the amplification factor of the filtered working current signal by the amplifier U3 is greater than or equal to 50 times. The signal conditioning module 5 is connected with the control module 1, and is configured to receive motion information driven by the voice coil motor, that is, receive motion information of the mechanical system collected by the sensor, and feed back the motion information to the control module 1.

The utility model discloses an foretell amplifier U3 carries out high accuracy operational amplification to the working current signal (being current sampling signal) of gathering, has guaranteed the precision of final output to control module 1's working current signal, can realize control module 1 to the accurate control of voice coil motor electric current to the realization is to voice coil motor's the control of exerting oneself, improves voice coil motor's power accuse precision.

Further, the amplifier U3 includes a first signal input terminal (VINA-, VINA +, VINB-, VINB +), a second signal input terminal (VIND-, VIND +, VINC-, VINC +), and a first signal output terminal (VOUTA, VOUTB) corresponding to the first signal input terminal and a second signal output terminal (VOUTD, VOUTC) corresponding to the second signal input terminal. The first signal input terminal is connected to the output terminal of the filtering unit 42, the second signal input terminal is connected to the first signal output terminal, and the second signal output terminal is connected to the control module 1. The working current signal collected by the current sampling unit 41 enters the amplifier U3 through the first signal input end after being filtered by the filtering unit 42, then enters the amplifier U3 for the second time through the second signal input end after being output from the first signal output end, and finally is output to the control module 1 through the second signal output end.

Optionally, the amplifier U3 is a high precision operational amplifier MCP 6294.

Specifically, as shown in fig. 4 and 5, the H-bridge driving unit 21 includes a first driving chip U1 and a second driving chip U2. The control module 1 outputs a first complementary PWM driving signal and a second complementary PWM driving signal through logic operation, the first driving chip U1 is used for amplifying the first complementary PWM driving signal, and the second driving chip U2 is used for amplifying the second complementary PWM driving signal.

Optionally, the model of the first driver chip is LM5109 BMAX.

Optionally, the model of the second driver chip is LM5109 BMAX.

Specifically, as shown in fig. 4 and 5, the H-bridge switch unit 22 mainly includes a first N-channel MOS transistor Q1, a second N-channel MOS transistor Q2, a third N-channel MOS transistor Q3, and a fourth N-channel MOS transistor Q4. The gate of the first N-channel MOS transistor Q1 is connected to the first output terminal (corresponding to pin 7) of the first driver chip U1, and the gate of the second N-channel MOS transistor Q2 is connected to the second output terminal (corresponding to pin 5) of the first driver chip U1. The first N-channel MOS transistor Q1 and the second N-channel MOS transistor Q2 are connected in series between the power module 3(VCC _ BUS) and the ground, and the common terminal of the first N-channel MOS transistor Q1 and the second N-channel MOS transistor Q2 is connected to one end of the voice coil motor. The grid of the third N-channel MOS transistor Q3 is connected to the first output terminal (corresponding pin 7) of the second driver chip U2, the grid of the fourth N-channel MOS transistor Q4 is connected to the second output terminal (corresponding pin 5) of the second driver chip U2, the third N-channel MOS transistor Q3 and the fourth N-channel MOS transistor Q4 are connected in series between the power module 3(VCC _ BUS) and the ground, and the common terminal of the third N-channel MOS transistor Q3 and the fourth N-channel MOS transistor Q4 is connected to the other end of the voice coil motor. The power module 3 is a dc linear voltage-stabilized power supply, and outputs a motor power supply from the VCC _ BUS end after voltage conversion, voltage stabilization and the like.

The first complementary PWM driving signal comprises two complementary PWM driving signals L1+ and L1-, and the second complementary PWM driving signal comprises two complementary PWM driving signals L2+ and L2-. Signals L1+ and L1-are amplified by the first driving chip U1 and then input to the first N-channel MOS tube Q1 and the second N-channel MOS tube Q2 so as to control the connection and disconnection of the first N-channel MOS tube Q1 and the second N-channel MOS tube Q2 respectively. Signals L2+ and L2-are amplified by the second driving chip U2 and then input to the third N-channel MOS tube Q3 and the fourth N-channel MOS tube Q4 so as to control the on-off of the third N-channel MOS tube Q3 and the fourth N-channel MOS tube Q4 respectively. When the first N-channel MOS transistor Q1 and the fourth N-channel MOS transistor Q4 are turned on, the motor current (VCC _ BUS) flows through the first N-channel MOS transistor Q1, the voice coil motor, and the fourth N-channel MOS transistor Q4 in sequence, and the driving power L1 is output to the voice coil motor. When the second N-channel MOS transistor Q2 and the third N-channel MOS transistor Q3 are turned on, the motor current (VCC _ BUS) flows through the third N-channel MOS transistor Q3, the voice coil motor, and the second N-channel MOS transistor Q2 in sequence, and the driving power L2 is output to the voice coil motor.

Optionally, the model of the first N-channel MOS transistor Q1 is IRFR120 NTRPBF.

Optionally, the model of the second N-channel MOS transistor Q2 is IRFR120 NTRPBF.

Optionally, the model of the third N-channel MOS transistor Q3 is IRFR120 NTRPBF.

Optionally, the model of the fourth N-channel MOS transistor Q4 is IRFR120 NTRPBF.

Specifically, as shown with continued reference to fig. 4 and 5, the current sampling unit 41 includes a first sampling resistor R9 and a second sampling resistor R18. The first sampling resistor R9 is connected in series between the second N-channel MOS transistor Q2 and the ground, and the second sampling resistor R18 is connected in series between the fourth N-channel MOS transistor Q4 and the ground. As described above, when the motor current (VCC _ BUS) sequentially flows through the first N-channel MOS transistor Q1, the voice coil motor, and the fourth N-channel MOS transistor Q4, the current sampling signals PL2+ and PL 2-in the power supply circuit for driving the voice coil motor are output through the second sampling resistor R18. When the motor current (VCC _ BUS) sequentially flows through the third N-channel MOS transistor Q3, the voice coil motor, and the second N-channel MOS transistor Q2, current sampling signals PL1+ and PL 1-in the power supply circuit driving the voice coil motor are output through the first sampling resistor R9.

Optionally, the resistances of the first sampling resistor R9 and the second sampling resistor R18 are 0.01 Ω.

Specifically, as shown in fig. 6, the filtering unit 42 includes a first filtering circuit and a second filtering circuit. The first filter circuit comprises a first filter resistor R19, a first filter capacitor C5, a second filter resistor R20 and a first sampling resistor R9 which are sequentially connected to form a ring filter circuit. The second filter circuit comprises a third filter resistor R25, a second filter capacitor C8, a fourth filter resistor R26 and a second sampling resistor R18 which are sequentially connected to form a ring filter circuit. As mentioned above, the current sampling signals PL1+ and PL 1-are filtered by the first filter circuit, then respectively input to the amplifier U3 through the first signal input terminal VINA-and the first signal input terminal VINA +, then output from the first signal output terminal VOUTA, then input to the amplifier U3 through the second signal input terminal VIND-and the second signal input terminal VIND + for the second time, and finally output from the second signal output terminal VOUTD. Similarly, the current sampling signals PL2+ and PL 2-are filtered by the second filter circuit, then respectively pass through the first signal input terminal VINB-and the first signal input terminal VINB + and are input to the amplifier U3, and then pass through the second signal input terminal VINC-and the second signal input terminal VINC + and are input to the amplifier U3 for the second time after being output from the first signal output terminal VOUTB, and finally are output from the second signal output terminal VOUTC.

In particular, and with continued reference to fig. 3 and 6, the current sampling module 4 further includes a protection unit 44, where the protection unit 44 includes a first protection circuit and a second protection circuit. The first protection circuit mainly includes a first resistor R38, a second resistor R37, a first capacitor C13, and a first switching diode unit D7. The current sampling signals PL1+ and PL 1-are filtered by the first filter circuit and then input to the amplifier U3, amplified by the amplifier U3 and output from the second signal output terminal VOUTD, and input to the first protection circuit through the first resistor R38, and output to the control module 1 through the first protection circuit and finally output to the current sampling signal DSP _ ADCL 1. The second protection circuit mainly includes a third resistor R40, a fourth resistor R39, a second capacitor C14, and a second switching diode unit D8. The current sampling signals PL2+ and PL 2-are filtered by the second filter circuit, input to the amplifier U3, amplified by the amplifier U3, output from the second signal output terminal VOUTC, input to the second protection circuit through the third resistor R40, and output to the control module 1 through the second protection circuit, the final current sampling signal DSP _ ADCL 2.

Specifically, as shown in fig. 2, the control module 1 includes a pulse width modulation unit 11, an analog-to-digital conversion unit 12 whose output end is connected to the input end of the pulse width modulation unit 11, and a pulse counting unit 13. The output end of the pulse width modulation unit 11 is connected to the input end of the H-bridge driving unit 21, and is used for outputting a PWM driving signal. The input end of the analog-to-digital conversion unit 12 is connected with the output end of the current sampling module 4, and the input end of the pulse counting unit 13 is connected with the output end of the signal conditioning module 5.

Specifically, the signal conditioning module 5 includes a third filter circuit and a digital logic circuit (not shown).

Please refer to fig. 7, which is a block diagram of a power control driving circuit of a voice coil motor according to another embodiment of the present invention, the power control driving circuit of the voice coil motor mainly includes a DSP controller module (corresponding to the control module 1 in fig. 1), a driving bridge module (corresponding to the driving bridge module 2 in fig. 1) composed of an H-bridge driving chip (corresponding to the H-bridge driving unit 21 in fig. 1) and an H-bridge (corresponding to the H-bridge switching unit 22 in fig. 1), a dc power supply module (corresponding to the power supply module 3 in fig. 1), a current sampling circuit module (corresponding to the current sampling module 4 in fig. 1), and a signal conditioning module (corresponding to the signal conditioning module 5 in fig. 1). The DSP controller module provides PWM driving signals for the drive axle module, the direct current power supply module provides power for the voice coil motor through a switch of an H bridge, the current sampling circuit module collects real-time working current of the voice coil motor and feeds the real-time working current back to an ADC (analog-to-digital conversion) circuit of the DSP controller module, and the signal conditioning module feeds motion information collected by the sensor back to a QEP (pulse counting circuit) of the DSP controller module. In this embodiment, the functions and corresponding connection relationships of the modules are the same as those of the modules in the previous embodiment, and for brevity, are not described again here.

With continued reference to fig. 7, the voice coil motor force control driving circuit further includes a display module and a function expansion module connected to the DSP controller module, where the function expansion module includes a human-computer interaction and communication interface circuit.

The above embodiments of the present invention are only described, and it should be noted that, for those skilled in the art, modifications can be made without departing from the inventive concept, but these all fall into the protection scope of the present invention.

Claims

1. A voice coil motor force control driving circuit is characterized by comprising a control module, a drive bridge module, a power supply module, a current sampling module and a signal conditioning module; the drive axle module comprises an H-bridge drive unit and an H-bridge switch unit connected with the H-bridge drive unit, the control module outputs a PWM drive signal, and the H-bridge drive unit is used for amplifying the PWM drive signal; the power supply module provides a motor power supply for the voice coil motor through the H-bridge switch unit; the current sampling module comprises a current sampling unit, a filtering unit and a signal double-stage amplifying unit which are sequentially connected, the current sampling unit is used for collecting working current signals of the voice coil motor in real time, the signal double-stage amplifying unit comprises an amplifier, the amplification factor of the amplifier to the working current signals filtered by the filtering unit is greater than or equal to 50 times, and the amplifier is connected with the control module; the signal conditioning module is connected with the control module and used for receiving the motion information driven by the voice coil motor.

2. A voice coil motor force control driving circuit according to claim 1, wherein the amplifier comprises a first signal input terminal, a second signal input terminal, and a first signal output terminal corresponding to the first signal input terminal and a second signal output terminal corresponding to the second signal input terminal, the first signal input terminal is connected to the filtering unit, the second signal input terminal is connected to the first signal output terminal, and the second signal output terminal is connected to the control module.

3. The voice coil motor force-controlled driving circuit according to claim 1, wherein the H-bridge driving unit includes a first driving chip and a second driving chip, the control module outputs a first complementary PWM driving signal and a second complementary PWM driving signal, the first driving chip is configured to amplify the first complementary PWM driving signal, and the second driving chip is configured to amplify the second complementary PWM driving signal.

4. The voice coil motor force control driving circuit according to claim 3, wherein the H-bridge switching unit comprises a first N-channel MOS transistor, a second N-channel MOS transistor, a third N-channel MOS transistor, and a fourth N-channel MOS transistor, a gate of the first N-channel MOS transistor is connected to the first output terminal of the first driving chip, a gate of the second N-channel MOS transistor is connected to the second output terminal of the first driving chip, the first N-channel MOS transistor and the second N-channel MOS transistor are connected in series between the power module and the ground, a common terminal of the first N-channel MOS transistor and the second N-channel MOS transistor is connected to one end of the voice coil motor, a gate of the third N-channel MOS transistor is connected to the first output terminal of the second driving chip, and a gate of the fourth N-channel MOS transistor is connected to the second output terminal of the second driving chip, the third N-channel MOS tube and the fourth N-channel MOS tube are connected in series between the power module and the ground, and the common end of the third N-channel MOS tube and the common end of the fourth N-channel MOS tube are connected with the other end of the voice coil motor.

5. The voice coil motor force control driving circuit according to claim 4, wherein the current sampling unit comprises a first sampling resistor and a second sampling resistor, the first sampling resistor is connected in series between the second N-channel MOS transistor and the ground, and the second sampling resistor is connected in series between the fourth N-channel MOS transistor and the ground.

6. The voice coil motor force control driving circuit of claim 5, wherein the filtering unit comprises a first filtering circuit and a second filtering circuit; the first filter circuit comprises a first filter resistor, a first filter capacitor, a second filter resistor and the first sampling resistor which are sequentially connected to form an annular filter circuit; the second filter circuit comprises a third filter resistor, a second filter capacitor, a fourth filter resistor and a second sampling resistor which are sequentially connected to form an annular filter circuit.

7. The voice coil motor force control driving circuit according to claim 1, wherein the current sampling module further comprises a protection unit, the protection unit comprises a first protection circuit and a second protection circuit, the first protection circuit is respectively connected with the amplifier and the control module, and the first protection circuit comprises a first resistor, a second resistor, a first capacitor and a first switching diode unit; the second protection circuit is respectively connected with the amplifier and the control module, and comprises a third resistor, a fourth resistor, a second capacitor and a second switch diode unit.

8. The voice coil motor force control driving circuit according to claim 1, wherein the control module comprises a pulse width modulation unit, an analog-to-digital conversion unit and a pulse counting unit, the pulse width modulation unit outputs the PWM driving signal, the analog-to-digital conversion unit is respectively connected with the current sampling module and the pulse width modulation unit, and the pulse counting unit is respectively connected with the signal conditioning module and the pulse width modulation unit.

9. The voice coil motor force control driver circuit of claim 1, wherein the signal conditioning module comprises a third filter circuit and a digital logic circuit.

10. The voice coil motor force-controlled driving circuit according to claim 1, further comprising a display module and a function extension module connected with the control module, wherein the function extension module comprises a man-machine interaction and communication interface circuit.