JPH0622590A - Load driver - Google Patents

Abstract

PURPOSE:To prevent generation of through current by providing voltage level converting means and pulse generating means for supplying different pulses to control terminals of a switching element from a reference signal and a control signal. CONSTITUTION:A control circuit 60 for executing a pulse width modulation of a pulse generator 21 has differential amplifiers in pulse generators 21. Any one reference signal is input to any one of its non-inverting input terminal and an inverting input terminal, and one control signal is input to the other one of the non-inverting and inverting input terminals. At the times of forward and reverse driving a load driver 30 by transistors 1-4, pulse width modulation drive is conducted by using the transistors 2, 4. At the time of reflux, the transistor 3 is turned ON at the time of forward driving, the transistor 1 is turned ON at the time of reverse driving, thereby bypassing the reflux to a power source through flywheel diodes 7-10. As a result, generation of through current in the case of driving can be easily prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load body drive device, and more particularly, to a load body drive device such as a motor in the case of switching the recirculation of the load body and changing the drive direction. The present invention relates to a load body drive device having a function of preventing a through current flowing through a drive circuit composed of transistors and the like.

[0002]

2. Description of the Related Art Conventionally, when a load driving device such as a motor is driven to rotate or slide, a plurality of switching elements such as transistors are arranged and each switching element is appropriately selected to turn on / off. A method of driving the load driving body by, for example, generating an induction magnetic field or a rotating magnetic field by turning off and supplying a predetermined current in a predetermined direction has been generally adopted. .

That is, as shown in FIG. 4, for example, when the load driving device is a DC motor, the first power source (Vc
The first transistor Q1 and the second transistor Q2 are arranged in series with each other between c) and the second power supply (GND), and the first power supply and the second power supply are connected to each other. The third transistor Q3 and the fourth transistor Q4 are connected to each other in series, and the first transistor Q1 and the second transistor Q2 are connected to each other. The first terminal T1 and the second terminal T2 of the motor M are respectively connected between the node portion N1 and the node portion N2 to which the third transistor Q3 and the fourth transistor Q4 are connected. It consists of things.

Then, for example, the first transistor Q1 and the fourth transistor Q4 are turned on, and the second transistor Q2 and the third transistor Q are turned on.
3 is turned off and a current is caused to flow in the direction of the arrow I1, the motor M is rotated in the first direction, and conversely, the first transistor Q1 and the fourth transistor Q1 are rotated. By turning off the transistor Q4 and turning on the second transistor Q2 and the third transistor Q3 and flowing a current in the direction of arrow I2,
The motor M will rotate in a second direction opposite to the first direction.

However, in the load body drive device having the above-mentioned structure, for example, in the load body drive device, when the circulation of the drive body is switched and the rotation direction is switched, each of the transistors described above is used. On the other hand, it is necessary to supply reverse drive signals in order to switch the ON / OFF states, respectively. In that case, due to the difference between the switching timing of the control signal and the operating characteristic of each transistor,
For example, the first transistor Q1 and the second transistor Q2 may be turned on at the same time, and similarly, the third transistor Q3 and the fourth transistor Q4 may be turned on at the same time. There was a problem that a large amount of shoot-through current occurred and flowed through the transistor.

Such a shoot-through current not only increases the power consumption of the load body drive device, but also causes deterioration of the transistor of the switching element that constitutes the load body drive device. In order to solve such a problem, in the prior art, for example, Japanese Unexamined Patent Publication No. 62-293981.
As shown in FIG. 3, when the switching elements which are alternately switched are turned on at the same time, one of them is turned on to prevent a through current from flowing. It has been proposed that an R delay circuit delays turning on and the other turns off first.

However, in this technique, the capacitor constituting the delay circuit usually exceeds the capacitance value that can be realized in the IC chip, so that when the control circuit is integrated, an external capacitor is required. Also, the delay time of the delay circuit is C.I. R In particular, there is a problem that it is difficult to optimally design the capacitor, because the variation and temperature characteristic of the capacitor are usually large.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems in the prior art, to easily prevent the generation of a through current when driving the load driving device, and at the same time, to perform the switching. So that the elements do not turn on at the same time,
(EN) Provided is a load body drive device in which the degree of margin can be freely set in consideration of the characteristics of a switching element used.

[0009]

In order to achieve the above-mentioned object, the present invention basically adopts the technical constitution as described below. That is, a load driver and a plurality of switching elements are provided, and the driving means capable of selectively driving the load driver in at least one of two opposite directions and the switching elements of the driving means are selectively operated. And a control means for turning the power on and off, wherein the control means is a reference signal generating means having a predetermined amplitude and frequency, and a control having a frequency smaller than the frequency of the reference signal. From the basic signal input means, the voltage level conversion means for generating at least two kinds of control signals having different voltage levels from the control basic signal, and the reference signal and the control signal, to the respective control terminals of the switching element. On the other hand, it is a load body drive device including pulse generation means for supplying different pulses.

[0010]

As described above, the load driving device according to the present invention uses, for example, a triangular wave oscillation signal having a predetermined amplitude and frequency as the reference signal and a frequency smaller than the frequency of the triangular wave oscillation signal as the control signal. At the same time, by using a signal wave that can be superimposed on the reference signal, and by performing an appropriate pulse width modulation on both of them by an appropriate differential amplifier, pulse width modulation in which the pulse widths in the ON state do not overlap with each other. Generate a pulse, thereby at least
When the first transistor Q1 and the second transistor Q2 are simultaneously turned on, and the third transistor
It is possible to completely eliminate the case where the transistor Q3 and the fourth transistor Q4 are simultaneously turned on.

More specifically, in the present invention, in the pulse width modulation drive system using the triangular wave oscillation signal, the control signal level for the control signal for cutting the triangular wave is set to a predetermined voltage. 2 shifted up and down by level
Since the pulse width modulation is executed by setting the seed control level, it is possible to arbitrarily change the pulse width modulation by arbitrarily changing the voltage level of the control signal. Since the timing of turning ON / OFF the transistors forming the element can be arbitrarily changed and set, it is possible to freely set the margin for preventing the occurrence of the through current.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific example of a load body driving device according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a specific example of a load driving device according to the present invention, in which a load driving body 20 and a plurality of switching elements 1 to 4 are included.
Driving means 50 capable of selectively driving at least one of two opposite directions and switching elements 1 to 4 of the driving means 50 are selectively turned ON / OFF.
Load body drive device 4 including control means 60
0, the control means 60 includes reference signal generating means 14 and 15 having a predetermined amplitude and frequency, and the reference signal S.
a control basic signal input means 11 having a frequency smaller than the frequency of _ref , at least two control signals S _CONT1 having different voltage levels from the control basic signal S _CONT ,
Voltage level converting means 12 and 13 for generating S _CONT2 , the reference signal S _ref, and the control signals S _CONT1 and S
There is shown a load body driving device 40 composed of _CONT2 and pulse generating means 21 for supplying different pulses to the respective control terminals of the switching elements 1 to 4.

Here, the drive means 50 of the load body drive device 40 according to the present invention is for rotating the load drive body 20 composed of, for example, a DC motor or a pulse motor in forward and backward arbitrary directions at any time. It may be provided, or a predetermined load may be moved and slid in the left-right direction. Further, the driving means 50 of the load body driving device 40 according to the present invention is, for example, as shown in FIG.
A first power source (eg Vdd) 5 and a second power source (eg Vdd)
ss) 6 and a first transistor 1 and a second transistor 2 are arranged in a state of being connected in series with each other, and between the first power source 5 and the second power source 6. A third transistor 3 and a fourth transistor 4 are connected to each other in series, and a node portion N1 to which the first transistor 1 and the second transistor 2 are connected and The first terminal T1 and the second terminal T2 of the load body 20 to be driven are respectively connected between the node portion N2 to which the third transistor 3 and the fourth transistor 4 are connected. The drive system is composed of.

It goes without saying that each of the above-mentioned transistors 1 to 4 constitutes a switching element in the present invention. It is shown that the transistor, which is the switching element in the driving means 50 in the present invention, is composed of a field effect (MOSFET) transistor as an example. As such a transistor, a bipolar transistor is used. It is also possible.

If necessary, for example, flywheel diodes 7 to 10 may be connected in parallel to the transistors 1 to 4 constituting the switching element in the present invention. The operation of the driving means 50 according to the present invention described above is basically the same as that of the conventional example described above, and the operation of the H bridge connected between the first feeder line 5 and the second feeder line 6 is performed. 4 N-channel type M
The OSFETs 1 to 4 drive the motor 20 in the forward and reverse directions. In the normal rotation, the transistor 1 is always on, the transistor 2 is always off, and the transistor 4 is driven by pulse width modulation on the low voltage side. A current flows in the direction indicated by and rotates the motor 20 in the forward direction. Further, since the transistor 3 driven exclusively with the transistor 4 is turned on during the return, the loss during the return is reduced as compared with the case where the flywheel diode 9 alone returns.

On the other hand, during reverse rotation, the transistor 3 is always on, the transistor 4 is always off, the transistor 2 is driven by pulse width modulation on the low voltage side, and a current flows in the direction indicated by I2 to rotate the motor 20 in the opposite direction. Let Since the transistor 1 driven exclusively with the transistor 2 is turned on during the return, the loss during the return is reduced as compared with the case where the flywheel diode 7 only returns.

Next, the reference signal generating means 14 and 15 in the control means 60 for driving and controlling the load body driving means 50 used in the load body driving device according to the present invention.
For generating a reference signal S _ref having a predetermined amplitude and frequency, which is generated by the first reference signal generating means 14 and is generated by the first reference signal S _ref1 and the second reference signal generating means 15. It is basically preferable that the second reference signal S _ref2 generated from the same has the same amplitude and the same frequency, but it is not a limiting element.

However, in the present invention, the first
The reference signal S _ref1 and the second reference signal S _ref2 are provided with a difference in the average voltage level at the center thereof, and if the first reference signal S _ref1 has a high voltage,
It is desirable that the second reference signal S _ref2 has a voltage lower than the voltage of the first reference signal S _ref1 to the extent that their amplitudes do not overlap.

Specifically, as shown in FIG. 2A, the first reference signal S _ref1 and the second reference signal S _{ref2 are}
Means, preferably, a first power supply 5 is placed in the middle of the power supply, for example
dd and the second power source 6 is Vss, for example,
The voltage levels of both may be selected and determined so that the voltage level represented by 1/2 (Vdd + Vss) is set.

In the present invention, the drive means 50 of the load body driving device described above controls the load drive body 20 by using the above-mentioned pulse width modulation method, for example, when the load drive body 20 is rotated forward or backward. To do this, as shown in Figure 2,
It uses two types of triangular wave oscillation signals, that is, a first reference signal S _ref1 and a second reference signal S _ref2 ,
Reference signal S _ref1 of, which is generated from said first reference signal generating means 14 to the load drive unit 20, for example, the purpose of reversing, and the second reference signal S _{re f2} is the load drive unit 20 Is generated by the second reference signal generating means 15 for the purpose of normal rotation, and it is preferable that the amplitude and the frequency are the same.

Further, as described above, the first reference signal S _ref1 and the second reference signal S _ref2 have the voltage levels of both reference signals so that the amplitudes of both waveforms do not overlap, as shown in FIG. Are preferably different. That is, in the present invention, the two reference signals S _ref1 and S _ref2 are designed to have as wide an amplitude as possible in the range above and below and not overlapping with each other about 1/2 of the power supply voltage. Is preferred.

Further, the control basic signal in the load driving device according to the present invention is not particularly limited, but a waveform having a frequency smaller than the frequencies of the both reference signals, that is, the wavelength is the reference signal. It is preferable to have a waveform longer than the wavelength, and the amplitude thereof is, as shown in FIG. 2, an amplitude in a range where it can intersect with the respective signal waveforms of the first reference signal S _ref1 and the second reference signal S _ref2. It is preferable to have

Further, in the present invention, the control basic signal is input to the input terminal IN of the control basic signal input means 11, and then the first voltage connected to the output of the control basic signal 11. The level converting means 12 and the second voltage level converting means 13 generate two kinds of control signals S _CONT1 and S _CONT2 having different voltage levels, and the voltage levels of both are, for example, the first voltage level. The voltage level of the first control signal S _CONT1 by the conversion means 12 is set to a low level, and the voltage level of the second control signal S _CONT2 by the second voltage level conversion means 13 is set to a high level. A signal waveform as shown in 2 is formed.

The voltage level difference between the two control signals in the present invention is not particularly limited, but it may be a variation in the switching element or the temperature characteristic of the driving means in the load driving device of the present invention. It is possible to set an appropriate voltage difference in consideration. Further, since such a configuration is adopted, in the present invention, the margin can be freely set with respect to the through current prevention condition in the load body drive device, and therefore, it is optimal for the load body drive device. It is possible to set various through current prevention conditions.

On the other hand, in the present invention, the above-mentioned first
Reference signal S_ref1And the second reference signal S _ref2And control signal S
_CONT1, S_CONT2From the pulse generation means 21,
Switching elements 1 to 1 constituting the drive circuit 50
Drive pulse with predetermined pulse width modulation applied to each of 4
Signal to select each of the switching elements.
Alternatively, ON / OFF drive may be performed to positively move the load driving body 20.
It controls reversing and reversing.

The pulse generating circuit 21 according to the present invention
May be composed of, for example, a plurality of differential amplifiers 16 to 19, and in that case, the outputs of the differential amplifiers 16 to 19 are the same as those of the switching elements 1 to 4 described above. A control terminal, that is, a base terminal of the switching element when the switching element is a bipolar transistor,
When it is a MOSFET, it becomes a logic signal for driving its gate terminal.

As described above, since each differential amplifier circuit of the pulse generating circuit 21 in the present invention selectively drives each switching element ON / OFF,
It is necessary that each has a function of generating a pulse signal whose pulse width is modulated so that each has a predetermined waveform. Further, in the present invention, the pulse width modulation processing in the pulse generation circuit is performed such that at least the first transistor 1 and the second transistor 2 are not simultaneously turned on. It is preferable that the modulated pulse signals have such waveforms that the ON states of both pulse signals do not overlap each other.

Next, the pulse generating circuit according to the present invention
Control circuit 60 for executing pulse width modulation processing in
An example of the internal configuration will be described with reference to FIG. That is,
Basically, the configuration of the control circuit of the present invention is
The pulse generating circuit includes a differential amplifier,
Either the non-inverting input terminal or the inverting input terminal of the amplifier
When any one of the above reference signals is input to the input terminal
The other input of the non-inverting input terminal and the inverting input terminal
Configured so that one control signal is input to the terminal
It is configured like this, but a more specific configuration
To explain, the control basic signal Sb has the first voltage level.
The first control signal S_{CO NT1}First voltage level to convert to
Conversion means 12 and a voltage level higher than the first voltage level.
Second control signal S having_CONT2Second electric to convert to
Pressure level converting means 13, first having a first voltage level
Reference signal S_ref1Generating means 14, the first reference signal S
_ref1A second reference signal having a second voltage level lower than
Issue S_ref2Generating Means 15, Control Theory of First Transistor 1
The output terminal for generating
2 control signal S_CONT2Is input to the non-inverting input terminal
Reference signal S of 1_ref1First pulse generation circuit to which is input
16, an output for generating the control logic of the second transistor 2.
Input terminal, and the inverting input terminal has the first reference signal S
_ref1Is input to the non-inverting input terminal of the first control signal S
_CONT1Is input to the second pulse generation circuit 17
Has an output terminal that generates the control logic of the transistor 3.
The second reference signal S at the inverting input terminal._ref2Is entered
The non-inverting input terminal receives the first control signal S_CONT1Is entered
Third pulse generating circuit 18 and fourth transistor 4
Has an output terminal for generating the control logic of
To the second control signal S_CONT2Is input to the non-inverting input terminal
Second reference signal S_ref24th pulse generation time
And the path 19.

Next, the control procedure of the control means 60 according to the present invention will be described with reference to FIG. 2 and FIG.
In the above, the period D1 indicates the period in which the load driving body 20 reverses, and the period D2 indicates the period in which the load driving body 20 rotates in the normal direction. Then, in the period D1, the first control signal S _CONT1 and the second control signal S
_CONT2 are both set so as to intersect only the first reference signal S _ref1, intersections a1 and the second control signal S _CONT2 to the first reference signal S _ref1, a2, a3 ···
With the a6 as a trigger, the pulse generation circuit 16 outputs a pulse-width-modulated control pulse as shown in the waveform (a) of FIG. 5, which becomes the logic of the control terminal of the first transistor 1.

On the other hand, the first control signal S _CONT1 and the first control signal S _CONT1
Intersections b1, b2, b3 with the reference signal S _{ref1 of}
Using b6 as a trigger, the pulse generating circuit 17 outputs a pulse-width-modulated control pulse as shown in the waveform (b) of FIG. 5, which serves as drive logic for the control terminal of the second transistor 2. Also, the second reference signal S _ref2 is
The first control signal S _CONT1 and the second control signal S _CONT2
Of the first control signal S _CONT1
And the second control signal S _CONT2 are both higher than the voltage level of the second reference signal S _ref2 , the pulse generation circuit 18
In this case, the voltage as shown in the waveform (c) of FIG. 5 is output, and this becomes the drive logic of the control terminal of the third transistor 3, so that the third transistor 3 is turned on.

Further, the pulse generating circuit 19 outputs a voltage as shown in the waveform (d) of FIG. 5, which is the fourth voltage.
The driving logic of the control terminal of the transistor 4 is that the fourth transistor 4 is in the OFF state. As a result, in the load driving means 50, I2 shown in FIG.
Current flows in the direction of, and thus the load driver 20 is reversed.

During this period, the first transistor 1 and the second transistor 2 are alternately turned on / off in accordance with the pulse waveforms (a) and (b) of FIG. 5, but both transistors are turned on at the same time. The situation is completely prevented. In the period D2, the first control signal S
_CONT1 and has a second control signal S _{CO NT2} are both set so as to intersect only the second reference signal S _ref2, the intersection of the first control signal S _CONT1 and the second reference signal S _ref2 .. c7 is used as a trigger to output a pulse-width-modulated control pulse as shown in the waveform (c) of FIG. 5 in the pulse generation circuit 18, and the third pulse is generated.
The driving logic of the control terminal of the transistor 3 of FIG.

On the other hand, the second control signal S _CONT2 and the second control signal S _CONT2
Intersections d1, d2, d3 with the reference signal S _{ref2 of} ...
Using d7 as a trigger, the pulse generating circuit 19 outputs a pulse-width-modulated control pulse as shown in the waveform (d) of FIG. 5, which serves as drive logic for the control terminal of the fourth transistor 4. Further, the first reference signal S _ref1 is
The first control signal S _CONT1 and the second control signal S _CONT2
Of the first control signal S _CONT1
And the second control signal S _CONT2 are both lower than the voltage level of the first reference signal S _ref1.
In this case, a voltage as shown in the waveform (a) of FIG. 5 is output, and this becomes the driving logic of the control terminal of the first transistor 1, so that the first transistor 1 is turned on.

Further, the pulse generating circuit 17 outputs a voltage as shown in the waveform (b) of FIG. 5, which is the second voltage.
Since the control logic of the control terminal of the transistor 2 is used, the second transistor 2 is turned off. As a result, in the load driving means 50, I1 shown in FIG.
A current flows in the direction of, and thus the load driver 20 rotates in the normal direction.

During this period, the third transistor 3 and the fourth transistor 4 are alternately turned on / off in accordance with the pulse waveforms (c) and (d) of FIG. 5, but both transistors are turned on at the same time. The situation is completely prevented. That is, in the present invention, the triangular wave oscillation signal which is the reference signal and the control signal intersecting with the reference signal are compared by the pulse generation circuit, and the first control signal is generated in the region where the control signal is lower than the reference signal. The transistor 1 of is turned on, and the second transistor 2 is turned off.

Further, in the region where the control signal is higher than the reference signal, the first transistor 1 is turned off and the second transistor 2 is turned on. Note that the operations of the third and fourth transistors have a relationship opposite to the above relationship. Further, in the present invention, the transistor ON / OF
The F operation may be reversed.

In the present invention, as shown in FIG. 1, four switching elements, that is, transistors 1 to 4 are used.
In order to drive the load driving body 20 such as a motor in forward and reverse directions, particularly, by using the reference signal composed of two types of triangular waves and the two types of control signals, the load driving body 20 is driven in the transistor 2 during forward and reverse driving. The pulse width modulation drive is performed using the transistor 4, and the current flowing back to the power supply via the flywheel diode is bypassed by turning on the transistor 3 at the time of forward rotation and the transistor 1 at the time of reverse rotation at the time of return. It is possible to reduce the loss of the diode. In order to prevent the through current from flowing through the transistors 1 and 2 or the transistors 3 and 4 at the same time at the time of switching back and forth and switching between forward and reverse in the configuration of the load driving device described above. The input signal Sb, which is a control signal for cutting the triangular wave, is shifted by the same voltage in the vertical direction by the voltage level converting means 12 and 13, and these signals and the first reference signal generated from the reference signal generating means 14 and 15 are used. Pulse width modulation is performed on the two triangular waves that are the second reference signals by using the differential amplifiers 16 to 19 that are pulse generation means so that the transistors 1 and 2 or the transistors 3 and 4 are not simultaneously turned on. The width-modulated control pulse is generated to perform no-overlap driving.

In the present invention, in the case of open loop control, it is necessary to shift the input signal Sb for cutting the triangular wave in the vertical direction by the same voltage, but in the case of closed loop feedback control, It is not necessary to shift the input signal up and down, and an input signal that cuts the original triangular wave and a signal obtained by shifting this signal up or down by a predetermined voltage may be used.

The effect of preventing shoot-through current is that the lower the frequency during pulse width modulation, that is, the lower the frequency of the triangular wave oscillation signal,
It's a big one. Further, in the present invention, the driving means 50 of the load driving body has four switching elements arranged in an H-bridge configuration and used as a driving circuit. Or transistor 3
And 4, the above-mentioned triangular wave oscillating signal and the input signal that cuts off the triangular wave in the output configuration in which the transistor connected to the high-side or high-potential power supply 5 and the transistor connected to the low-side low-potential power supply are connected in series. Comparing with the above, it is applicable to all as long as it has a configuration to exclusively drive one of the transistors 1 and 2 or the transistors 3 and 4 depending on the height.

Further, in the present invention, an example in which the switching elements 2 and 4 among the four switching elements 1 to 4 in FIG. 1 are driven by pulse width modulation has been described, but the switching elements 1 and 3 are described. Needless to say, the pulse width modulation drive may be used. Further, in the present invention, the example in which the switching element is composed of the N-channel type MOSFET has been described, but the switching element may be composed of the P-channel type MOSFET.

FIG. 3 shows a load body driving device 40 according to the present invention.
Shows an example in which is applied to an electronic throttle system of an engine. In the figure, a concrete example of a device for controlling the opening of the throttle valve 38 by a throttle valve opening command signal voltage 31 is shown. A throttle position sensor 39 indicates the present position of the throttle valve. The detected position information, that is, the throttle position sensor output voltage 32 is input to the feedback control circuit (for example, PID control circuit) 33.

The feedback control circuit 33 outputs a control signal 34 for cutting off the reference signal composed of the triangular wave in accordance with the throttle position sensor output voltage 32. The control signal is as described above. There are two types of signals that depend on the voltage level of each other. The control signal is input to the load body drive unit 35 composed of the drive unit 50 and the control unit 60 in FIG. 1, and the motor 36 for rotating the throttle valve 38 by a predetermined angle.
It outputs a pulse-width-modulated pulse control signal for rotating the device in a predetermined direction by a predetermined angle.

The rotation amount of the motor 36 is transmitted to the throttle valve 38 via the reduction gear 37, for example.
The throttle valve 38 is moved to a predetermined position and adjusted to a predetermined opening.

[0044]

Since the load body drive device according to the present invention has the above-mentioned technical structure, it is possible to easily prevent the generation of a through current when the load body drive device is driven, and at the same time, It is possible to obtain a load driving device in which the degree of margin can be freely set in consideration of the characteristics of the switching elements used so that the switching elements do not turn on at the same time.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a specific example of a load driving device according to the present invention.

FIG. 2 is a diagram showing an example of waveforms of a control signal and a reference signal used in the present invention, respectively.

FIG. 3 is a diagram illustrating an example in which the load driving device according to the present invention is applied to a throttle valve opening adjustment mechanism in a throttle system.

FIG. 4 is a diagram illustrating an example of a configuration of a conventional load body driving device.

FIG. 5 is a diagram showing an example of a waveform of a control pulse output from the control circuit in the load driving device according to the present invention.

[Explanation of symbols]

 1 to 4 ... Switching element, transistor 5 ... High potential power supply 6 ... Low potential power supply 7-10 ... Diode 11 ... Control basic signal 12 ... First control signal generating means 13 ... Second control signal generating means 14 ... First Reference signal generating means 15 ... Second reference signal generating means 16 to 19 ... Pulse generating circuit, differential amplifier 20 ... Load driver, motor 21 ... Pulse generating means 31 ... Throttle valve opening command signal 32 ... Throttle valve position Signal 33 ... Feedback control circuit 34 ... Control signal 35 ... Load driving device 36 ... Motor 37 ... Reduction gear 38 ... Throttle valve 39 ... Throttle valve position sensor 40 ... Load driving device 50 ... Driving means 60 ... Control means

Claims (13)

[Claims] 1. A driving device including a load driving body and a plurality of switching elements, capable of selectively driving the load driving body in at least one of two opposite directions, and respective switching elements of the driving means. ON selectively
/ OFF control means for controlling the load, wherein the control means is a reference signal generating means having a predetermined amplitude and frequency, and a control basic signal having a frequency smaller than the frequency of the reference signal. From the input means, the voltage level conversion means for generating at least two kinds of control signals having different voltage levels from the control basic signal, and the reference signal and the control signal, to the respective control terminals of the switching element. And a load driving device comprising pulse generating means for supplying mutually different pulses. 2. The load body drive device according to claim 1, wherein the load drive body is a motor. 3. The load body drive device according to claim 1, wherein the drive means selectively and selectively drives the load drive body in two forward and reverse directions. 4. The load body driving device according to claim 1, wherein the switching element in the driving means is composed of a transistor. 5. The driving means is such that at least four switching elements are arrayed, and the switching elements are configured so that two switching elements form a pair, and the respective pairs operate differently from each other. The load body drive device according to claim 3, wherein the load body drive device is controlled so as to perform the following. 6. The pulse generating means in the control means is composed of a plurality of pulse generating circuits each having an output of a drive logic of each control terminal of the switching element. The load driving device described. 7. The load driving device according to claim 6, wherein the pulse generating circuit has a function of generating a pulse having a pulse width modulated. 8. The load driving device according to claim 1, wherein the reference signal generating means is configured to generate at least two types of reference signals having different voltage levels. 9. Each of the pulse generating circuits includes a differential amplifier, and one of the non-inverting input terminal and the inverting input terminal of the differential amplifier has one of the reference signals. And a control signal of one of the non-inverting input terminal and the other input terminal of the inverting input terminal is input.
The load driving device described. 10. A first voltage level converting means for converting the control basic signal into a first control signal having a first voltage level, and a second control signal having a voltage level higher than the first voltage level. Second voltage level converting means for converting, first reference signal generating means having a first voltage level, second reference signal generating means having a second voltage level lower than the first reference signal, The control terminal of the first transistor has an output terminal for driving logic, and the inverting input terminal has the second terminal.
Control signal is input and a first reference signal is input to a non-inverting input terminal, a first pulse generating circuit, and a drive logic output terminal for a control terminal of a second transistor. It has a second pulse generating circuit to which the first reference signal is input and the first control signal is input to the non-inverting input terminal, and an output terminal for driving logic of the control terminal of the third transistor, and an inverting input terminal An inverting input terminal having a third pulse generating circuit to which the second reference signal is input and a first control signal to a non-inverting input terminal, and an output terminal for driving logic of a control terminal of a fourth transistor, 10. The load driving device according to claim 9, further comprising: a fourth pulse generating circuit to which a second control signal is input and a second reference signal is input to a non-inverting input terminal. 11. The load driving device according to claim 4, wherein the switching element is composed of either a bipolar transistor or a field effect transistor. 12. The first and second reference signals are triangular wave oscillation signals, and the first and second control signals derived from the control basic signal are the first and second control signals.
10. The load driving device according to claim 9, wherein the load driving device has a frequency lower than that of the second reference signal and has a voltage level that intersects with the first and second reference signals. 13. The first switching element and the fourth switching element form one pair, and the second switching element and the third switching element form the other pair, and The switching element of the pair and the switching element of the other pair are selectively set in mutually opposite driving states, and the first switching element and the second switching element are the first switching element. Is controlled by a pulse output from the second pulse generation circuit and pulse width modulated so as to have pulse widths that do not overlap each other, and when one switching element is in the ON state, the other switching element is OFF. The third switching element and the fourth switching element are controlled to be in the state
And the fourth pulse generation circuit, which is controlled by the pulse width-modulated pulses having pulse widths that do not overlap each other, and one switching element is turned on.
11. When in the state, the other switching elements are controlled so as to be in the OFF state.
The load driving device described.