CN1312645C - Piezoelectric conversion drive - Google Patents

Abstract

A piezoelectric conversion driving device is used for components or products which need to be driven at high voltage or low voltage. The device comprises: the driving module is composed of a single Pulse Width Modulation (PWM) control unit and a single driving unit, and outputs driving signals with the same phase and frequency to drive the plurality of conversion units, the plurality of piezoelectric units and the plurality of loads to act.

Description

Piezoelectric conversion drive

technical field

The present invention relates to a piezoelectric conversion drive device, especially a piezoelectric conversion drive device that uses a single pulse width modulation (PWM) control unit and a single drive unit to drive multiple conversion units, piezoelectric units and loads. .

Background technique

The light source required for the liquid crystal display (LCD) used in commercially available desktop and notebook computers, PDAs, and Webpads is driven by a driving device to drive cold cathode lamps (CCFL) with high voltage, so that the light is projected to the backlight panel. The user can clearly see the displayed picture.

Especially for LCD TVs or LCD displays with additional touch film, higher brightness is required to compensate for visual requirements. A general drive device for driving cold cathode lamps is shown in Figure 1. This device uses a single pulse width modulation (PWM) control unit to drive a single drive unit, and then uses a single drive unit to drive a transformer and a load (cold cathode lamp). The cold cathode lamp uses high voltage to light the lamp. When the tube current is higher, the brightness is brighter.

When the brightness and uniformity of the backlight are insufficient, multiple lamps are often used. At this time, the number of pulse width modulation control units, drive units, and transformers for driving and lighting also increases, resulting in larger circuit boards, resulting in difficulty in production and cost. Increase.

Contents of the invention

The main purpose of the present invention is to solve the defects of the above-mentioned prior art and avoid the existence of the defects. The present invention uses a single pulse width modulation (PWM) control unit and drive unit to drive multiple conversion units, piezoelectric units and load actions to reduce the number of parts and shrink the circuit board, making the production easier and the relative production cost also reduce.

In order to achieve the above-mentioned purpose, the piezoelectric conversion driving device of the present invention includes: a driving module composed of a single pulse width modulation (PWM) control unit and a single driving unit, and the output of the driving module is in the same phase and in the same phase. Frequency driving signals are used to drive a plurality of conversion units, a plurality of piezoelectric units, and a plurality of loads.

Description of drawings

The relevant technical content and structure of the present invention are now described in detail in conjunction with the accompanying drawings as follows.

FIG. 1 is a schematic circuit diagram of a conventional cold cathode lamp driving device.

Fig. 2 is a schematic diagram of the first embodiment of the present invention.

Fig. 3 is a schematic diagram of the second embodiment of the present invention.

Detailed ways

Referring to Fig. 2, it is a schematic diagram of the first embodiment of the present invention. As shown in the figure: the piezoelectric conversion driving device of the present invention is used for components or products that need to be driven by high voltage or low voltage. Driven conversion unit 2, a plurality of piezoelectric units 3 connected to the aforementioned plurality of conversion units 2 and driven synchronously, and a plurality of loads 4 connected to the aforementioned piezoelectric units 3 and driven synchronously, by means of the aforementioned driving module Generate a drive signal output with the same phase and frequency, so that the drive signal can drive multiple conversion units 2 and multiple piezoelectric units 3 to drive multiple loads 4 to act simultaneously. Since the number of parts is reduced, the circuit board is reduced, which makes the production easier, and the relative production cost is also reduced.

The drive module 1 mentioned above is composed of a single pulse width modulation (PWM) control unit 11 and a single drive unit 12. The aforementioned pulse width modulation (PWM) control unit 11 is driven by outputting signals with the same phase and frequency. Unit 12, the driving unit 12 is composed of a MOS metal oxide semiconductor element, after being driven by the same-phase and same-frequency signal output by the aforementioned pulse width modulation (PWM) control unit 11, it will generate a driving signal output.

Among the plurality of conversion units 2 , each conversion unit 2 is composed of an inductor for converting the signal output by the above-mentioned driving module 1 .

In the plurality of piezoelectric units 3, each piezoelectric unit 3 is composed of any one of a single plate or a laminated piezoelectric sheet or a transformer, and can be used as an output of boosting and stepping down. At the same time, any piezoelectric unit 3. Connect a voltage feedback to the above-mentioned pulse width modulation (PWM) control unit 11, and any load 4. Connect a current feedback to the pulse width modulation (PWM) control unit 11 to feed back a current to allow the pulse The PWM control unit 11 can sense the current of the load 4 so that the PWM control unit 11 can control the average current of the load 4 .

The loads 4 are components or products that need to be driven by high voltage or low voltage, such as cold cathode fluorescent lamps, ozone generators, negative ion generators, etc.

When the drive module 1 is activated by an external power supply, the pulse width modulation (PWM) control unit 11 outputs a signal with the same phase and frequency to drive the drive unit 12 to operate. After one conversion unit 2 is converted, it can drive multiple piezoelectric units 3, causing each piezoelectric unit 3 to drive each load 4 to act; at the same time, the load 4 is connected to a current feedback to the pulse width modulation (PWM) control The unit 11 senses the current of the load 4 so that the pulse width modulation (PWM) control unit 11 can control the average current of the load 4 so that the load 4 can be driven on average.

Referring to Fig. 3, it is a schematic diagram of the second embodiment of the present invention. As shown in the figure: this embodiment is roughly the same as the above-mentioned embodiment, the difference lies in that after the single pulse width modulation (PWM) control unit 11a of the drive module 1a drives the single drive unit 12a, the two-way conversion unit 2a is used And piezoelectric unit 3a to drive a single load 4a. At the same time, the two piezoelectric units 3a output a pair of voltages with opposite phases to the load 4a, so that the characteristics of uniform output current, larger power output and better impedance matching can be obtained, and a single pulse width modulation (PWM) control unit 11a can be used. Simultaneously drive multiple groups of loads 4a.

Claims (7)

1. piezoelectric type conversion driving device is characterized in that this device includes:

One drives module (1), in order to export a drive signal;

A plurality of converting units (2) are connected with above-mentioned driving module (1), and are driven the drive signal that module (1) exported and drive;

A plurality of piezoelectric units (3) are connected with above-mentioned a plurality of converting units (2), and the signal that exported by converting unit (2) drives;

A plurality of loads (4) be connected with above-mentioned a plurality of piezoelectric units (3), and the signal that exported by piezoelectric unit (3) drive;

The described a plurality of converting units of wherein said driving module driven in synchronism, a plurality of piezoelectric unit and a plurality of load;

Wherein said driving module (1) is made of single pulse-width modulation (PWM) control module (11) and single driver element (12); And

Wherein said pulse-width modulation (PWM) control module (11) is in order to the signal of output same-phase and same frequency.

2. piezoelectric type conversion driving device according to claim 1 is characterized in that, this driver element (12) is made of a MOS metal-oxide semiconductor element.

3. piezoelectric type conversion driving device according to claim 1 is characterized in that, this piezoelectric unit (3) adopts any structural design of individual layer or lamination.

4. piezoelectric type conversion driving device according to claim 1 is characterized in that this converting unit (2) is made of inductance.

5. piezoelectric type conversion driving device according to claim 1 is characterized in that described load is any in cold cathode fluorescent lamp pipe, ozone generation device, the anion generator.

6. piezoelectric type conversion driving device according to claim 1 is characterized in that, drives single load (4) with converting unit (2) and the piezoelectric unit (3) that drives module (1) driving two-way.

7. piezoelectric type conversion driving device according to claim 6 is characterized in that, this two piezoelectric unit (3) is exported the opposite voltage of a pair of phase place to load (4).

Images