KR0177992B1 - H-bridge type dc motor driving circuit - Google Patents

Abstract

A DC motor and an H-bridge push-pull output stage circuit unit configured to control the power supplied to the DC motor according to a predetermined rotation control drive signal to the first channel or the second channel to rotate the DC motor forward or reverse; A push-pull driving circuit unit which controls the rotation direction of the DC motor by controlling current opening and closing of the first channel and the second channel of the push-pull circuit unit, respectively, and the push- at the time of changing the rotation direction of the DC motor. The DC motor is rotated forward by the drive output circuit of the H-bridge DC motor by providing a delay circuit part which pulls down the rotation switching control signal applied to the input terminal of the full drive circuit part for a predetermined time and temporarily delays the time of the rotation change command. Reduces power consumption by reducing leakage current generated when switching from reverse rotation to reverse rotation or reverse rotation to forward rotation In addition, the present invention relates to a drive output circuit of an H-bridge DC motor which can solve the problem of power supply noise or ground noise.

Description

Drive output circuit of H-bridge DC motor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an H-bridge DC motor, and in particular, an operation start time of an H-bridge transistor by pulling down a certain amount of current applied to a rotation control driving transistor controlling forward and reverse rotation in the H-bridge DC motor. The present invention relates to a drive output circuit of an H-bridge DC motor which can greatly reduce the leakage current generated when the rotation direction of the motor is changed by delaying.

In general, when a pair of switch elements of the H-bridge is 'on' at the same time in the output stage switch element for driving the motor, a very large current flows through the current path of the two elements (hereinafter referred to as 'leakage current'). In order to prevent such a phenomenon, the switch element is destroyed or the current consumption increases, and in order to prevent the above-mentioned phenomenon, as long as it is 'on / off', the section to be 'on' at the same time should be reduced as much as possible.

The driving circuit of the conventional H-bridge DC motor reversely rotates with the output transistors Q1 and Q4 for forward rotation of the H-bridge DC motor M having two channels to the output terminal of the push-pull as shown in FIG. There are output stage transistors Q2 and Q3, which are connected so as to be alternately driven with respect to two input signals IN A and IN B inputted to the respective rotation control drive transistors QA and QB.

When the first input signal IN A of the two input signals IN A and IN B is logic 'high', the forward rotation driving transistor QA is operated to connect the first transistor Q1 connected to the push-pull output terminal. And the fourth transistor Q4 are turned on to form a current channel, and the motor M is powered by current paths of the first and fourth transistors Q1 and Q4 and starts to rotate forward.

On the contrary, when the second input signal IN B is logic 'high', the reverse rotation driving transistor QB operates to turn on the second transistor Q2 and the third transistor Q3 to form a current channel. Rotate the motor (M) in reverse.

However, in the H-bridge output terminals OUTA and OUTB having the above-described configuration, FIG. 2A and 2B according to the change of the two input signals IN A and IN B inputted to the respective rotation control driving transistors QA and QB. When the motor M is rotated in the forward rotation or in the forward rotation due to the same driving voltage, the motor M is driven by the logic 'high' of one input signal IN A in the H-bridge state. The motor M is rotated in reverse by the logic 'high' of the other input signal IN B.

For example, when the motor M rotates forward, when the other input signal IN B becomes logic 'high', the second transistor Q2 is turned on and the third transistor Q3 is turned on. M) starts reverse rotation.

However, at this time, since the fourth transistor Q4 does not turn off completely but gradually turns off with a certain delay time, the second transistor Q2 to the fourth transistor Q4 at the same moment as shown in FIG. When leakage current flows and changes from reverse rotation to forward rotation, similarly, leakage current flows from the output transistor of the first transistor Q1 to the current path of the third transistor Q3, which causes unnecessary power loss and grounding. There was a problem of generating noise and power supply noise.

An object of the present invention is to output a H-bridge output stage by temporarily delaying a direction change command by pulling down the rotation control current applied to an input terminal of a driving transistor that controls the rotation direction of the motor when the DC motor changes the rotation direction. To provide a drive output circuit of the H-bridge DC motor to reduce the leakage current generated in the transistor.

In order to achieve the above object, the apparatus of the present invention, a direct current electric motor; An H-bridge push-pull output stage circuit unit configured to control the power supplied to the DC motor according to a predetermined rotation control drive signal to the first channel or the second channel to rotate the DC motor forward or reverse; A push-pull driving circuit unit controlling the rotation direction of the DC motor by controlling current opening and closing of the first channel and the second channel of the push-pull circuit unit, respectively; And a delay circuit for temporarily delaying the rotation conversion command time by pulling down the rotation switching control signal applied to the input terminal of the push-pull driving circuit part for a predetermined time at the time of changing the rotation direction of the DC motor.

1 is a driving circuit diagram of a conventional H-bridge DC motor,

2 is an output waveform diagram when the motor is driven by the positive and reverse rotation input signals of FIG. 1, FIG. 2A is a voltage waveform diagram applied to both ends of the motor according to an input change, and FIG. 2B is a push-pull output terminal according to an input change. Is a waveform diagram showing a leakage current flowing through a transistor,

3 is a circuit diagram showing the driving circuit of the H-bridge DC low concentration machine according to an embodiment of the present invention,

4 is a circuit diagram showing a driving circuit of the H-bridge DC motor according to another embodiment of the present invention,

5 is an output waveform diagram when the motor is driven by the positive and reverse rotation input signals of FIGS. 3 and 4, and FIG. 5 is a waveform diagram of voltage across the motor according to the input change. A waveform diagram showing leakage current flowing through a push-pull output transistor according to an input change.

* Explanation of symbols for main parts of the drawings

10: Push-pull output circuit part of H-bridge M: DC motor

Q1-Q4: Push-Pull Output Transistors of H-Bridge

Q1-Q4: First forward rotation channel Q2-Q3: Second reverse rotation channel

20: push-pull driving circuit section QA, QB: rotation control driving transistor

30, 50: delay circuit section Q5, Q6: pull-down transistor

Q7 ~ Q9, Q10 ~ Q12: Current Meter

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

3 is a circuit diagram showing a drive output circuit of the H-bridge DC motor according to an embodiment of the present invention, a DC motor (M), H-bridge push-pull output stage circuit unit 10, push-pull drive circuit unit 20 ) And a delay circuit section 30 is provided.

On the other hand, the H-bridge push-pull output stage circuit unit 10 is supplied with power to the first current channels Q1-Q4 and output stage transistors Q1 and Q4 for forward rotation of the DC motor M, and the second current. It consists of output stage transistors Q2 and Q3 which supply power to the channels Q2-Q3 and close the DC motor M in reverse rotation.

In addition, the push-pull driving circuit unit 20 is driven according to the push-pull rotation control signals IN A and IN B applied from the outside, so that the first of the H-bridge push-pull output stage transistors Q1 to Q4 is provided. It consists of forward and reverse rotation driving transistors QA and QB for selectively driving the output terminal transistors corresponding to the current channels Q1-Q4 and the second current channels Q2-Q3.

In addition, the delay circuit unit 30 outputs a predetermined rotation command input signal applied to the input terminal of the driving transistors QA and QB of the push-pull driving circuit unit 20 to output terminal transistors Q4 or Q3 of different rotation direction channels. It is composed of pull-down transistors Q5 and Q6 that pull down to ground voltage until V is completely turned off to reduce the leakage current generated in the H-bridge push-pull output stage circuit section 10.

The pull-down transistors Q5 and Q6 have current paths connected between the input signal terminals applied to the forward and reverse rotation driving transistors QA and QB and ground voltages, respectively, and output currents of the driving transistors QB and QA. Is configured to respond to each.

That is, when the first input signal IN A of the two input signals IN A and IN B applied to the push-pull driving transistors QA and QB is logic 'high', the forward rotation driving transistor QA Is operated to turn on the first transistor Q1 and the fourth transistor Q4 connected to the push-pull output terminal to form a current channel, and the motor M is connected to the first and fourth transistors Q1 and Q4. Power starts through the current path and starts to rotate forward.

On the contrary, when the second input signal IN B is logic 'high', the reverse rotation driving transistor QB operates to turn on the second transistor Q2 and the third transistor Q3 to form a current channel. Rotate the motor (M) in reverse.

In order to prevent the phenomenon in which the second transistor Q2 is 'on' when the fourth transistor Q4 is not completely 'off' when the motor M is switched from the normal rotation to the reverse rotation direction. By pulling down the current applied to the transistor QB through the sixth pull-down transistor Q6, the timing at which the second transistor Q2 is 'on' is somewhat delayed. This is because the sixth pull-down transistor Q6 is turned on by the output current of the forward rotation driving transistor QA, and the reverse rotation is performed only during the period in which the sixth pull-down transistor Q6 is 'on'. Is to delay somewhat.

Of course, when the motor M is rotated from reverse rotation to forward rotation, the first transistor Q1 is pulled down by the current applied to the forward rotation driving transistor QA through the fifth pull-down transistor Q5. Delays the 'on' of This is because the fifth pull-down transistor Q5 is turned on by the output current of the reverse rotation driving transistor QB, and the forward rotation is performed only during the period in which the fifth pull-down transistor Q5 is 'on'. Is to delay somewhat.

It is preferable to use N-type transistors for the fifth and sixth pull-down transistors Q5 and Q6 of the delay circuit unit 30.

4 is a diagram illustrating a driving circuit of the H-bridge DC motor according to another embodiment of the present invention. The DC motor M, the H-bridge push-pull output stage circuit unit 10, and the push-pull driving circuit unit 20 are illustrated in FIG. ) And a delay circuit section 50.

On the other hand, the H-bridge push-pull output stage circuit unit 10 is supplied with power to the first current channels Q1-Q4 and output stage transistors Q1 and Q4 for forward rotation of the DC motor M, and the second current. It consists of output stage transistors Q2 and Q3 which receive power from the channels Q2-Q3 and reversely rotate the DC motor M.

In addition, the push-pull driving circuit unit 20 is driven according to the push-pull rotation control signals IN A and IN B that are applied from the outside and is the first of the H-bridge push-pull output stage transistors Q1-Q4. It consists of forward and reverse rotation driving transistors QA and QB for selectively driving the output terminal transistors corresponding to the current channels Q1-Q4 and the second current channels Q2-Q3.

In addition, the delay circuit unit 50 supplies a predetermined rotation command input signal applied to the input terminal of the push-pull driving circuit unit 20 until the output stage transistors Q4 or Q3 of other rotation direction channels are completely turned off. And a current mirror circuit Q7-Q9 and Q10-Q12 which pull-down to the ground voltage and reduce the leakage current generated in the H-bridge push-pull output stage circuit section 10.

The delay circuit unit 50, which is operated when switching from the forward rotation to the reverse rotation of the motor M, has a current path connected between the power supply voltage and the collector end of the transistor Q8, which is used as a diode of the current mirror. A current path is connected between the seventh transistor Q7 in response to the output signal of the collector terminal of the forward rotation driving transistor QA, the collector terminal of the seventh transistor Q7, and the ground voltage, and responds to the output signal of the collector terminal. The diode-type eighth transistor Q8 and the base and the base of the eighth transistor Q8 are connected to the ninth transistor Q9 having a current path connected between the input terminal of the reverse rotation driving transistor QB and the battery voltage. Consists of.

In addition, the delay circuit section 50, which is operated when the motor is switched from reverse rotation to forward rotation, has a current path connected between the power supply voltage and the collector stage of the transistor Q11 that is used as a diode of the current mirror, thereby driving reverse rotation. A diode type in which a current path is connected between the tenth transistor Q10 in response to the output signal of the collector terminal of the transistor QB and the collector terminal and the ground voltage of the tenth transistor Q10 and responds to the output stage of the collector terminal. An eleventh transistor Q11, a base and a base of the eleventh transistor Q11 are connected, and a twelfth transistor Q12 having a current path connected between the input terminal of the forward rotation driving transistor QA and the ground voltage. have.

The seventh and tenth transistors Q7 and Q10 of the delay circuit unit 30 use P-type transistors, and the eighth, ninth, eleventh and twelfth transistors Q8, Q9, Q11, and Q12 are N-type. It is preferable to use a transistor.

That is, when one input signal IN A is logic 'high', the driving transistor QA and the H-bridge push-pull output transistors Q1-Q4 are turned on so that the motor M rotates forward and the other input is turned on. When the signal IN B is logic 'high', the driving transistor QB and the H-bridge output terminal transistors Q2 and Q3 are turned on and the motor M is reversely rotated. When the output terminal transistors Q1 and Q4 are turned on by the logic 'high' of the hysteresis signal IN A in the H-bridge state, the other input signal IN B becomes the logic ' When high, the output transistors Q2 and Q3 are turned on and the motor M starts to rotate in reverse.

However, at this time, the output stage transistor Q4 does not completely turn off and gradually turns off with a certain delay time, so that a leakage current flows from the reverse rotation output transistor Q2 to the forward rotation output transistor Q4. To improve, the current applied to the forward and reverse rotation driving transistors QA and QB is pulled down through the transistor Q9 of the current mirror when the rotation direction is changed, and the pull-down time controls the current source of the current mirror. It is determined by the on and off times of the transistor Q7.

When the seventh transistor Q7 of the current mirror is turned off, the reverse control current provided to the input terminal of the reverse rotation driving transistor QB according to the characteristics of the current mirror is no longer pulled down through the ninth transistor Q9. The fourth transistor Q4 of the forward rotation output stage is also turned off.

At this time, when the current for controlling the reverse rotation is applied to the reverse rotation driving transistor QB, the leakage current passing through the current paths of the second transistor Q2 and the fourth transistor Q4 can be reduced to the maximum.

When the motor M is changed from reverse rotation to forward rotation, the rotation control current IN A applied to the forward rotation drive transistor QA is similar to that of the reverse rotation from the forward rotation. By pulling down through the current path of the second transistor Q2, the time point at which the first transistor Q1 is 'on' is somewhat delayed.

In the H-bridge output stages OUTA and OUTB configured as shown in FIGS. 3 and 4, the two input signals IN A and IN B are inputted to the respective rotation control driving toristors QA and QB. The driving voltage shown in FIG. 5a is applied to rotate the motor M in forward rotation or forward rotation in reverse rotation.

In this case, as shown in FIG. 5A, the rotation control input signal IN A or IN B provided to the input terminal of the driving transistor QA or QB is pulled down for a predetermined time td and delayed to supply the fourth transistor. Q4) or the third transistor Q3 does not completely turn off the leakage current can be significantly reduced compared to the conventional second degree as shown in FIG.

As described above, in the present invention, the drive output circuit of the H-bridge DC motor can reduce the leakage current generated when the DC motor changes direction from forward rotation to reverse rotation or from reverse rotation to forward rotation, thereby consuming In addition to reducing power, problems with power supply and ground noise can be solved.

Claims (3)

DC motor; An H-bridge push-pull output stage circuit unit configured to control the power supplied to the DC motor according to a predetermined rotation control drive signal to the first channel or the second channel to rotate the DC motor forward or reverse; A push-pull driving circuit unit controlling the rotation direction of the DC motor by controlling current opening and closing of the first channel and the second channel of the push-pull circuit unit, respectively; And a delay circuit unit configured to temporarily delay the time of the rotation conversion command by pulling down the rotation switching control signal applied to the input terminal of the push-pull driving circuit unit for a predetermined time when the rotation direction of the DC motor is changed. Drive output circuit of H-bridge DC motor. 2. The circuit of claim 1, wherein the delay circuit part is applied to the input terminal of the push-pull driving circuit part and pull-out to the ground voltage until the output terminal transistor of the H-bridge push-pull output terminal circuit part of another rotational direction channel is completely turned off. Drive-down circuit of the H-bridge DC motor, characterized in that the pull-down transistor is configured to reduce the leakage current generated in the H-bridge push-pull output stage circuit portion The method of claim 1, wherein the delay circuit unit is pulled down to the ground voltage until the H-bridge push-pull output stage transistor of another rotational direction channel is applied to the input terminal of the push-pull driving circuit unit until it is completely turned off. And a current mirror circuit for reducing leakage current generated in the H-bridge push-pull output stage circuit unit.