TWI483537B - Driving circuit and driving method with energy recovery - Google Patents

Description

Driving circuit and driving method with energy recovery

The present invention relates to a driving circuit, and more particularly to a driving circuit with energy recovery.

According to FIG. 1A, it is a schematic diagram of a driving circuit 1a of a conventional piezoelectric device Z1. During a driving cycle, the switch Q2 is turned on, and the current I1 provided by the DC signal DC forms a driving circuit via the resistor R1, the piezoelectric device Z1 and the switch Q2 to drive the piezoelectric device Z1 to operate. However, in the driving circuit 1a, when the switch Q2 is turned on, there is a current I2. Therefore, regardless of whether the piezoelectric device Z1 operates or not, the current I2 flows through the resistor R2 and the switch Q2, and thus, the driving circuit 1a is not caused. The necessary power loss.

In order to improve the disadvantage of the drive circuit 1a, another drive circuit 1b is proposed. As shown in FIG. 1B, it is a schematic diagram of another driving circuit 1b of the conventional piezoelectric device Z2. During a driving cycle, the switches T1 and T4 are turned on, and the current I3 provided by the DC signal DC forms a driving circuit via the switch T1, the piezoelectric device Z2, and the switch T4 to drive the piezoelectric device Z2 to operate. During another driving cycle, the switches T2 and T3 are turned on, and the current I4 provided by the DC signal DC forms another driving circuit via the switch T2, the piezoelectric device Z2, and the switch T3 to drive the piezoelectric device Z2 to operate.

However, in the above-mentioned driving circuits 1a, 1b, only the piezoelectric elements of the piezoelectric devices Z1, Z2 are supplied with driving energy, and the piezoelectric elements are used to convert electrical energy into mechanical energy, so that the piezoelectric elements are deformed to achieve driving. purpose. However, the drive circuits 1a and 1b are ignored. When the supply of the drive energy to the piezoelectric devices Z1 and Z2 is stopped, the piezoelectric element is returned from the deformed state to the initial piezoelectric effect (direct piezoelectric effect). Characteristics of electrical energy). In other words, the conventional driving circuit 1a, 1b utilizes only the inverse piezoelectric effect of the piezoelectric element, but ignores the piezoelectric effect that the piezoelectric element returns from the deformed state to the initial state, that is, The electric energy generated by the piezoelectric element returning to the initial state from the deformed state is ignored. Of course, the driving circuits 1a and 1b cannot recover the electric quantity generated by the piezoelectric element in the piezoelectric effect, thereby achieving the purpose of power saving.

Therefore, how to provide a driving circuit and a driving method with energy recovery can have the advantages of energy recovery and have the effect of saving electricity, and has become one of important topics.

In view of the above problems, an object of the present invention is to provide a driving circuit capable of energy recovery and having a power saving effect and a driving method with energy recovery.

To achieve the above object, a driving circuit according to the present invention drives a piezoelectric device and includes a driving unit and a control unit. The driving unit is electrically connected to the piezoelectric device and has an energy storage component. The control unit is electrically connected to the driving unit and controls the driving unit to cause the piezoelectric device to emit a quantity of electricity to the energy storage element, so as to reflow the electric quantity and drive the piezoelectric device.

In an embodiment of the invention, the piezoelectric device has at least one piezoelectric element, and the driving circuit outputs a driving signal to deform the piezoelectric element to drive the piezoelectric device to operate.

In an embodiment of the invention, the piezoelectric device outputs a quantity of electricity when the piezoelectric element is deformed and the shape returns to the initial state.

In an embodiment of the invention, the driving unit further has a first switch and a second switch, and the first ends of the energy storage components are respectively powered by the first switch and the second switch. The piezoelectric device is connected.

In an embodiment of the invention, the control unit turns on one of the first switch and the second switch to store the power to the energy storage element and to reflow the power and drive the piezoelectric device.

In an embodiment of the invention, the piezoelectric element has a first electrical connection end and a second electrical connection end, and the driving signal is input to the first electrical connection end and the second electrical connection end to drive the pressure. Electrical device.

In one embodiment of the present invention, the first ends of the first switch and the second switch are electrically connected to the first electrical connection end and the second electrical connection end of the piezoelectric device, respectively.

In an embodiment of the invention, the first end of the energy storage component is electrically connected to the second end of the first switch and the second switch, and the second end of the energy storage component is electrically grounded.

In an embodiment of the present invention, the driving unit further has a third switch, a fourth switch, a fifth switch, and a sixth switch, and the direct current signal is respectively input to the first end of the third switch and the fourth switch. The second ends of the third switch and the fourth switch are electrically connected to the first electrical connection end and the second electrical connection end of the piezoelectric device, respectively.

In one embodiment of the present invention, the first ends of the fifth switch and the sixth switch are electrically connected to the second end of the third switch and the fourth switch, respectively, and the first electrical connection end and the second end of the piezoelectric device The electrical connection ends, the second ends of the fifth switch and the sixth switch are respectively grounded.

In an embodiment of the invention, the control unit simultaneously turns on the third switch and the sixth switch, so that the direct current signal is input to the first electrical connection end of the piezoelectric device via the third switch, and the second electrical property of the piezoelectric device The connection terminal is grounded via a sixth switch.

In an embodiment of the invention, the control unit simultaneously turns on the fourth switch and the fifth switch, so that the DC signal is input to the second electrical connection end of the piezoelectric device via the fourth switch, and the first electrical property of the piezoelectric device The connection terminal is grounded via the fifth switch.

In an embodiment of the invention, the control unit simultaneously turns on the first switch and the sixth switch to store the power to the energy storage element.

In an embodiment of the invention, the control unit simultaneously turns on the second switch and the fifth switch to cause the power to flow back and drive the piezoelectric device.

In an embodiment of the invention, the control unit simultaneously turns on the second switch and the fifth switch to store the power to the energy storage element.

In an embodiment of the invention, the control unit simultaneously turns on the first switch and the sixth switch to cause the power to flow back and drive the piezoelectric device.

In order to achieve the above object, a driving method with energy recovery according to the present invention is applied to a driving circuit for driving a piezoelectric device. The driving circuit has a first switch, a second switch, and a third switch. a fourth switch, a fifth switch, a sixth switch and an energy storage component, the driving method comprises the steps of: driving the piezoelectric device by turning on the third switch and the sixth switch; The switch and the sixth switch are configured to cause the piezoelectric device to discharge one of the power to the energy storage device; and to turn on the second switch and the fifth switch to cause the stored energy of the energy storage device to reflow and drive the piezoelectric device.

In an embodiment of the invention, the piezoelectric device has a piezoelectric element, and the driving circuit outputs a driving signal to deform the piezoelectric element to drive the piezoelectric device to operate.

In an embodiment of the invention, the piezoelectric device outputs a quantity of electricity when the piezoelectric element is deformed and the shape returns to the initial state.

In an embodiment of the invention, the control unit turns on one of the first switch and the second switch to store the power to the energy storage element and to reflow the power and drive the piezoelectric device.

In an embodiment of the invention, when the first switch and the sixth switch are simultaneously turned on, the power is stored to the energy storage element.

In an embodiment of the invention, when the second switch and the fifth switch are simultaneously turned on, the power is reflowed and the piezoelectric device is driven.

In an embodiment of the invention, when the second switch and the fifth switch are simultaneously turned on, the power is stored to the energy storage element.

In an embodiment of the invention, when the first switch and the sixth switch are turned on at the same time, the power is reflowed and the piezoelectric device is driven.

In an embodiment of the invention, the driving method further comprises the step of driving the piezoelectric device to act by turning on the fourth switch and the fifth switch.

In an embodiment of the invention, the driving method further comprises the step of: storing the power generated by the piezoelectric device to the energy storage element by turning on the second switch and the fifth switch.

In an embodiment of the invention, the driving method further comprises the steps of: turning on the first switch and the sixth switch to cause the stored energy of the energy storage element to reflow and drive the piezoelectric device.

According to the above description, a driving circuit and an energy recovery driving method according to the present invention drive a piezoelectric device, and the control unit controls the driving unit to store a quantity of electricity generated by the piezoelectric device to the driving unit. Inside the energy storage component. Additionally, the control unit can control the drive unit to cause the charge to reflow and drive the piezoelectric device. Thereby, the power generated by the piezoelectric effect of the piezoelectric device can be stored to the energy storage device through the driving circuit and the energy recovery driving method of the present invention, and the power stored in the energy storage device can be stored in the next driving cycle. Output to drive the piezoelectric device. Therefore, the driving circuit and the energy recovery driving method of the present invention have the advantages of energy recovery, and have power saving to achieve power saving effect. In addition, in an embodiment of the present invention, the driving circuit of the present invention and the driving method with energy recovery can increase the flow rate of the piezoelectric micropump output as compared with the prior art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a driving circuit in accordance with a preferred embodiment of the present invention will be described with reference to the accompanying drawings, wherein the same elements will be described with the same reference numerals.

2 and FIG. 3, wherein FIG. 2 is a functional block diagram of a driving circuit 2 according to a preferred embodiment of the present invention, and FIG. 3 is a circuit diagram of the driving unit 21 of FIG.

The drive circuit 2 includes a drive unit 21 and a control unit 22. The driving circuit 2 is used to drive a piezoelectric device 3, and the piezoelectric device 3 can be a portable or fixed device. Here, a portable piezoelectric micropump is taken as an example. Not limited to this. In addition, if the piezoelectric device 3 is a piezoelectric micropump, it can be applied to a small amount (ml or microliter) and a liquid or gas transport requiring precise flow control, and is not limited to which liquid or gas is used for transporting, As long as the liquid or gas delivered does not contain chemically reactive or aggressive components of the piezoelectric micropump itself. In addition, the piezoelectric micropump can be used for, but not limited to, only one drug delivery, and can also be applied to the mixing and dispensing of micropharmaceuticals.

The driving unit 21 is electrically connected to the piezoelectric device 3. The piezoelectric device 3 has at least one piezoelectric element 31. Here, a piezoelectric element 31 is taken as an example. Among them, the piezoelectric element 31 can generate an inverse piezoelectric effect (converted from mechanical energy into mechanical energy) and a positive piezoelectric effect (converted from mechanical energy into electrical energy). The piezoelectric element 31 is a piezoelectric material, and the piezoelectric material may be, for example, lead zirconate Titanate (PZT).

The driving circuit 2 outputs a driving signal DS to cause the piezoelectric element 31 to be deformed, thereby driving the piezoelectric device 3 to operate. In other words, as shown in FIG. 4A or FIG. 4B, in the present embodiment, the piezoelectric device 3 has a body 32, and the piezoelectric element 31 is disposed on the body 32. The body 32 can have at least one chamber R, and the piezoelectric element 31 is correspondingly disposed above the chamber R. In addition, the piezoelectric device 3 further has an actuating diaphragm 33 which covers the top of the chamber R and the piezoelectric element 31 is disposed above the actuating diaphragm 33. Here, the actuating diaphragm 33 is located between the piezoelectric element 31 and the chamber R. Wherein, the actuating diaphragm 33 is a thin glass with a high Young's modulus, and can completely accept the inverse piezoelectric effect of the piezoelectric element 31, and can generate sufficient thrust to deform the corresponding chamber R, thereby improving The back pressure of the piezoelectric device 3. In addition, the piezoelectric element 31 is closely adhered to the actuating diaphragm 33 by a conductive and viscous material such as a conductive silver paste.

As shown in FIG. 4A, the piezoelectric element 31 is deformed by the voltage application of the driving signal DS, and the actuating diaphragm 33 is interlocked to be bent upward. Alternatively, as shown in FIG. 4B, when the voltage of the driving signal DS is reversed, the piezoelectric element 31 is deformed by the voltage loading of the driving signal DS, and the actuating diaphragm 33 is interlocked to be bent downward. Therefore, when the piezoelectric element 31 is deformed by the driving of the driving signal DS, the actuating diaphragm 33 can be deformed, and the volume of the chamber R of the body 32 can be deformed. In this manner, the piezoelectric device 3 can be driven by the driving signal DS (here, the piezoelectric device 3 is a piezoelectric micropump) so that the fluid can be stably outputted through the piezoelectric device 3.

Regardless of the aspect of FIG. 4A or FIG. 4B, the driving signal DS produces an inverse piezoelectric effect on the piezoelectric element 31, causing the piezoelectric element 31 to be deformed. However, when the driving signal DS is removed, when the piezoelectric element 31 is returned to the initial flat state by the deformed state of FIG. 4A or FIG. 4B, it is known from the piezoelectric effect that the piezoelectric element 31 can emit a power E.

Referring to FIG. 2 again, the control unit 22 is electrically connected to the driving unit 21. The drive unit 21 has an energy storage component C. Here, the energy storage element C is a capacitor. The control unit 22 can control the drive unit 21 to store the amount of electricity E emitted from the piezoelectric device 3 to the energy storage element C. In addition, the control unit 22 can control the drive unit 21 to cause the electric quantity E to reflow and drive the piezoelectric device 3.

Referring to FIG. 3 again, it is further explained how the driving circuit 2 of the present invention recovers the amount of electricity E emitted from the piezoelectric device 3 and how the piezoelectric device 3 is driven by the amount of electricity E.

The driving unit 21 has a first switch S1 and a second switch S2, and the first end C1 of the energy storage device C is electrically connected to the piezoelectric device 3 through the first switch S1 and the second switch S2, respectively. The first end C1 of the energy storage device C is electrically connected to the second end S12 of the first switch S1 and the second end S22 of the second switch S2, and the second end C2 of the energy storage element C is electrically grounded. In addition, the control unit 22 can control the first switch S1 and the second switch S2 to be turned on or off. The control unit 22 turns on one of the first switch S1 and the second switch S2 to store the electric quantity E to the energy storage element C, and recirculates the electric quantity E and drives the piezoelectric device 3.

The piezoelectric element 31 has a first electrical connection end 311 and a second electrical connection end 312, and the driving signal DS is input to the first electrical connection end 311 and the second electrical connection end 312 to drive the piezoelectric device. 3. The first ends S11 and S21 of the first switch S1 and the second switch S2 are electrically connected to the first electrical connection end 311 and the second electrical connection end 312 of the piezoelectric device 3, respectively.

The driving unit 21 further has a third switch S3, a fourth switch S4, a fifth switch S5 and a sixth switch S6. A DC signal DC is input to the first ends S31 and S41 of the third switch S3 and the fourth switch S4, respectively. The second ends S32 and S42 of the third switch S3 and the fourth switch S4 are electrically connected to the first electrical connection end 311 and the second electrical connection end 312 of the piezoelectric device 3, respectively. The first ends S51 and S61 of the fifth switch S5 and the sixth switch S6 are electrically connected to the second ends S32 and S42 of the third switch S3 and the fourth switch S4, respectively, and the first electrical connection end 311 of the piezoelectric device 3 And the second electrical connection end 312, and the second ends S52 and S62 of the fifth switch S5 and the sixth switch S6 are respectively grounded.

Hereinafter, a method in which the driving unit 21 of the present invention drives the piezoelectric device 3, recovers the electric quantity E emitted from the piezoelectric device 3, and uses the electric quantity E to drive the piezoelectric device 3 will be described with reference to FIGS. 3 and 5. FIG. 5 is a flowchart of a driving method of the driving circuit 2 of the present invention.

The driving method of the present invention includes steps P01 to P03.

Step P01 is to drive the piezoelectric device 3 to operate by turning on the third switch S3 and the sixth switch S6 during a first driving cycle. The control unit 22 simultaneously turns on the third switch S3 and the sixth switch S6 so that the DC signal DC is input to the first electrical connection end 311 of the piezoelectric device 3 via the third switch S3, and the piezoelectric device 3 The two electrical connections 312 are grounded via a sixth switch S6. In other words, the control unit 22 simultaneously turns on the third switch S3 and the sixth switch S6 so that the current I5 provided by the DC signal DC can flow through the switch S3, the piezoelectric element 31, and the switch S6 to drive the piezoelectric device 3 to The piezoelectric element 31 is deformed.

Step P02 is to store the electric energy E emitted from the piezoelectric device 3 to the energy storage element C by turning on the first switch S1 and the sixth switch S6. Here, the control unit 22 simultaneously turns on the first switch S1 and the sixth switch S6 so that the electric energy E generated by the piezoelectric device 3 due to the piezoelectric effect (mechanical energy converted into electric energy) can be stored to the energy storage element. C.

Next, in step P03, the second switch S2 and the fifth switch S5 are turned on during a second driving cycle to cause the amount E stored in the energy storage device C to reflow and drive the piezoelectric device 3. The control unit 22 turns on the second switch S2 and the fifth switch S5 at the same time to recirculate the electric quantity E stored in the energy storage element C in the first driving period, and is used to drive the piezoelectric device 3. Since the amount of electricity E stored in the energy storage element C is the amount of electricity generated by the positive voltage effect of the piezoelectric device 3, the amount of electricity E is insufficient to fully drive the piezoelectric device 3 during the second driving cycle.

In addition, please also see Figure 3 and Figure 6. The driving method of the present invention may further include the step P04 of driving the piezoelectric device 3 by turning on the fourth switch S4 and the fifth switch S5. In this case, the control unit 22 simultaneously turns on the fourth switch S4 and the fifth switch S5, so that the DC signal DC is input to the second electrical connection terminal 312 of the piezoelectric device 3 via the fourth switch S4, and the piezoelectric device 3 is The one-piece connection terminal 311 is grounded via the fifth switch S5. In other words, the control unit 22 simultaneously turns on the fourth switch S4 and the fifth switch S5, so that the current I6 provided by the DC signal DC can flow through the switch S4, the piezoelectric element 31 and the switch S5 to drive the piezoelectric device 3 to operate. The electric quantity E of the step P03 is supplemented to drive the insufficient portion of the piezoelectric device 3.

Furthermore, the driving method may further include the step P05 of: storing the electric quantity E emitted from the piezoelectric device 3 to the energy storage element C by turning on the second switch S2 and the fifth switch S5. Here, the control unit 22 simultaneously turns on the second switch S2 and the fifth switch S5 so that the electric energy E generated by the positive voltage effect of the piezoelectric device 3 after the step P05 is driven can be stored to the energy storage element C.

Next, the driving method may further include step P06: turning on the first switch S1 and the sixth switch S6 to cause the amount E stored by the energy storage element C to reflow and drive the piezoelectric device 3. The control unit 22 turns on the first switch S1 and the sixth switch S6 at the same time, so that the electric quantity E stored in the energy storage element C in step P05 is recirculated and used to drive the piezoelectric device 3.

After step P06, step P01 to step P06 can be repeated, and the control unit 22 can control the third switch S3 to the sixth switch S6 of the driving unit 21 to be turned on and off in each driving cycle, so that the DC signal DC input voltage is pressed. The electric device 3 is operated to drive the piezoelectric device 3. In addition, the control unit 22 can simultaneously turn on the first switch S1 and the sixth switch S6 or the second switch S2 and the fifth switch S5 to recover the amount of electric energy E emitted when the piezoelectric element 31 returns to the initial state. In addition, the control unit 22 can simultaneously turn on the second switch S2 and the fifth switch S5 or the first switch S1 and the sixth switch S6 to reflow and drive the piezoelectric device 3 to recover the amount of electricity E recovered in the previous driving cycle.

In addition, it has been experimentally proved that when the driving circuit 2 with energy recovery of the present invention and the driving method thereof are used to drive a piezoelectric micro-pump operation, since the electric energy E stored in the energy storage element C is first reflowed to drive the piezoelectric micro-pump, Therefore, in the next driving cycle, when the current supplied by the DC signal DC drives the piezoelectric device 3, the flow rate of the piezoelectric micropumping fluid can be increased. In other words, when the piezoelectric signal micro-pump is driven by the DC signal DC of the same voltage level, the energy recovery drive circuit 2 and the driving method thereof can effectively improve the piezoelectric micro-pump transmission and distribution. Traffic.

In summary, a driving circuit and an energy recovery driving method according to the present invention drive a piezoelectric device, and the control unit controls the driving unit to store one of the power generated by the piezoelectric device to the driving unit. Inside the energy storage component. Additionally, the control unit can control the drive unit to cause the charge to reflow and drive the piezoelectric device. Thereby, the power generated by the piezoelectric effect of the piezoelectric device can be stored to the energy storage device through the driving circuit and the energy recovery driving method of the present invention, and the power stored in the energy storage device can be stored in the next driving cycle. Output to drive the piezoelectric device. Therefore, the driving circuit and the energy recovery driving method of the present invention have the advantages of energy recovery, and have power saving to achieve power saving effect. In addition, in an embodiment of the present invention, the driving circuit of the present invention and the driving method with energy recovery can increase the flow rate of the piezoelectric micropump output as compared with the prior art.

The above is intended to be illustrative only and not limiting. Any equivalent modifications or alterations to the spirit and scope of the invention are intended to be included in the scope of the appended claims.

1a, 1b, 2‧‧‧ drive circuits

21‧‧‧ drive unit

22‧‧‧Control unit

3. Z1, Z2‧‧‧ piezoelectric devices

31‧‧‧Piezoelectric components

311, 312, C1, C2, S11, S12, S21, S22, S31, S32, S41, S42, S51, S52, S61, S62‧‧‧

32‧‧‧Ontology

33‧‧‧ actuation diaphragm

C‧‧‧ Energy storage components

DC‧‧‧DC signal

DS‧‧‧ drive signal

E‧‧‧Power

I1~I6‧‧‧ Current

P01~P06‧‧‧Steps

Q1, Q2, S1~S6, T1~T4‧‧‧ switch

R‧‧‧室

R1, R2‧‧‧ resistance

1A is a schematic diagram of a driving circuit of a conventional piezoelectric device;

1B is a schematic diagram of a driving circuit of another piezoelectric device;

2 is a functional block diagram of a driving circuit according to a preferred embodiment of the present invention;

3 is a schematic circuit diagram of the driving unit of FIG. 2; FIG. 4A to FIG. 4B are schematic diagrams showing the operation of the piezoelectric device of the present invention; FIG. 5 is a flowchart of a driving method of the driving circuit of the present invention; A flowchart of another driving method of the driving circuit.

twenty one. . . Drive unit

31. . . Piezoelectric element

311, 312, C1, C2, S11, S12, S21, S22, S31, S32, S41, S42, S51, S52, S61, S62. . . end

C. . . Energy storage component

DC. . . DC signal

E. . . Electricity

I5, I6. . . Current

S1 ~ S6. . . switch

Claims (25)

A driving circuit for driving a piezoelectric device, comprising: a driving unit electrically connected to the piezoelectric device, and having a first switch, a second switch, a third switch, and a fourth switch, a fifth switch, a sixth switch, and an energy storage component; and a control unit electrically connected to the driving unit, the control unit turns on the first switch and the sixth switch to enable the piezoelectric device to emit One of the power is stored to the energy storage component, and the control unit further turns on the second switch and the fifth switch to cause the power to flow back and drive the piezoelectric device. The driving circuit of claim 1, wherein the piezoelectric device has at least one piezoelectric element, and the driving circuit outputs a driving signal to deform the piezoelectric element to drive the piezoelectric device to operate. The driving circuit of claim 2, wherein the piezoelectric device outputs the electric quantity when the piezoelectric element is deformed and the shape returns to an initial state. The driving circuit of claim 2, wherein the first end of the energy storage element is electrically connected to the piezoelectric device by the first switch and the second switch, respectively. The driving circuit of claim 4, wherein the control unit turns on one of the first switch and the second switch to store the power to the energy storage component, and to reflow and drive the power The piezoelectric device. The driving circuit of claim 4, wherein the piezoelectric element has a first electrical connection end and a second electrical connection end, and the driving signal is input to the first electrical connection end and the first Two electrical terminals are used to drive the piezoelectric device. The driving circuit of claim 6, wherein the first end of the first switch and the second switch are electrically connected to the first electrical connection end of the piezoelectric device and the second electrical property, respectively Connection end. The driving circuit of claim 7, wherein the first end of the energy storage element is electrically connected to the first end of the first switch and the second switch, and the second end of the energy storage element is electrically connected Sexual grounding. The driving circuit of claim 6, wherein the direct current signal is respectively input to the first end of the third switch and the fourth switch, and the second end of the third switch and the fourth switch are respectively respectively The first electrical connection end and the second electrical connection end of the piezoelectric device are connected. The driving circuit of claim 9, wherein the first end of the fifth switch and the sixth switch are electrically connected to the third end of the third switch and the fourth switch, respectively, and the piezoelectric device The first electrical connection end and the second electrical connection end, the fifth switch and the second end of the sixth switch are respectively grounded. The driving circuit of claim 9, wherein the control unit turns on the third switch and the sixth switch, so that the DC signal is input to the first electrical connection end of the piezoelectric device via the third switch. And the second electrical connection end of the piezoelectric device is grounded via the sixth switch. The driving circuit of claim 9, wherein the control unit turns on the fourth switch and the fifth switch, so that the DC signal is input to the second electrical connection end of the piezoelectric device via the fourth switch. And the first electrical connection end of the piezoelectric device is grounded via the fifth switch. The driving circuit of claim 9, wherein the control unit further turns on the second switch and the fifth switch to store the power to the energy storage element. The driving circuit of claim 9, wherein the control unit further turns on the first switch and the sixth switch to cause the power to flow back and drive the piezoelectric device. A driving method with energy recovery is applied to a driving circuit for driving a piezoelectric device. The driving circuit has a first switch, a second switch, a third switch, a fourth switch, and a fifth a driving method, comprising: switching the third switch and the sixth switch to drive the piezoelectric device to operate; and turning on the first switch and the a sixth switch for causing the piezoelectric device to discharge a quantity of power to the energy storage element; and by turning on the second switch and the fifth switch to cause the amount of electricity stored by the energy storage element to reflow and drive the pressure Electrical device. The driving method of claim 15, wherein the piezoelectric device has a piezoelectric element, and the driving circuit outputs a driving signal The piezoelectric element is deformed to drive the piezoelectric device to operate. The driving method of claim 16, wherein the piezoelectric device outputs the electric quantity when the piezoelectric element is deformed and the shape returns to an initial state. The driving method of claim 15, wherein the control unit turns on one of the first switch and the second switch to store the power to the energy storage element, and to reflow and drive the power The piezoelectric device. The driving method of claim 15, wherein the electric quantity is stored to the energy storage element when the first switch and the sixth switch are turned on. The driving method of claim 15, wherein when the second switch and the fifth switch are turned on, the electric quantity reflows and drives the piezoelectric device. The driving method of claim 15, wherein the electric quantity is stored to the energy storage element when the second switch and the fifth switch are turned on. The driving method of claim 15, wherein when the first switch and the sixth switch are turned on, the electric quantity reflows and drives the piezoelectric device. The driving method of claim 15, further comprising: driving the piezoelectric device by turning on the fourth switch and the fifth switch. The driving method of claim 15, further comprising: storing the electric quantity emitted by the piezoelectric device to the energy storage element by turning on the second switch and the fifth switch. The driving method of claim 15, further comprising: turning on the first switch and the sixth switch to cause the amount of electricity stored by the energy storage element to reflow and drive the piezoelectric device.