JPH07163184A - Driving circuit - Google Patents

Abstract

PURPOSE:To provide an H-type driving circuit having such characteristics as the current flowing into a load can be settled at a predetermined level in a short time at the time of switching the direction while preventing damage or erroneous function of the power supply components due to excessive flyback voltage. CONSTITUTION:The H-type driving circuit comprises four power supplies connected between a high potential side power supply VCC and a low potential side power supply VSS and subjected to conduction control with the direction of current flowing into a load being switched reversibly by a control signal, wherein a first rectifying element 5 is connected forward between a first power supply 1 and the joint of first and third power supplies 1, 3 and a second rectifying element 6 is connected forward between a second power supply 2 and the joint of second and fourth power supplies 2, 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive circuit in a semiconductor integrated circuit, and more particularly to an H-type drive circuit capable of changing the polarity of a current flowing through a load.

[0002]

2. Description of the Related Art Conventionally, an H-type drive circuit has been widely used as a drive circuit for a coil used in a motor, a coil used in a data write head of a magnetic disk device, etc., and controls the direction of a current flowing through the coil. By doing so, it is used to change the rotating direction of the motor and the moving direction of the data write head.

The circuit configuration and operation of a conventionally used H-type drive circuit will be described with reference to FIG. 14
In the H-type drive circuit in FIG. 1, a series circuit including a first current source 1 and a third current source 3 capable of controlling conduction between a high potential side power source V _CC and a low potential side power source V _SS, and a conduction controlling state, respectively. A series circuit including a possible second current source 2 and a fourth current source 4 is connected, a connection point between the first current source 1 and the third current source 3, a second current source 2 and a fourth current source A load can be connected between the connection point and the connection point 4.

In the case of FIG. 14, a load coil L is connected as a load. In the H-type drive circuit having the above configuration, the first current source 1 and the fourth current source 4, and the second current source 1
The direction of the current flowing through the load coil L is reversibly controlled by controlling the conduction between the current source 2 and the third current source 3 in an antiphase relationship with each other.

That is, the first current source 1 and the fourth current source 4
When is on (hereinafter referred to as ON state),
The second current source 2 and the third current source 3 are in the cutoff state (hereinafter, OFF state).
The state. ), The control is performed as shown in FIG.
Drive current I indicated by solid line arrow ₁Flows into the load.

Further, when the first current source 1 and the fourth current source 4 are in the OFF state, the second current source 2 and the third current source 3 are controlled to be in the ON state, so that the state shown in FIG. The drive current I ₂ indicated by the dashed arrow flows through the load.

With the above operation, the H-type drive circuit can reversibly control the direction of the current flowing through the load coil L.
In the conventional H-type drive circuit described above, an excessively large electromotive force (hereinafter referred to as flyback voltage) is generated at the moment when the direction of the current in the load coil L is switched, and this flyback voltage is applied. By being
There is a problem in that parts such as transistors forming each current source are damaged.

That is, as a general characteristic of the coil, a flyback voltage is generated in a direction to maintain the original current state at the moment when the current direction in the coil is switched.

Now, as an example, the drive current I ₁ shown in FIG.
Considering the case where the direction of the current flowing through the load is switched from the direction of the current to the direction of the drive current I ₂ , the first current is changed so as to maintain the direction of the current before switching at the moment when the direction of the current is switched. A negative flyback voltage is generated at the output terminal connected to the series circuit of the source 1 and the third current source 3, and the output terminal connected to the series circuit of the second current source 2 and the fourth current source 4. Generates a positive flyback voltage.

The value of the flyback voltage is proportional to the inductance of the load coil L and the current flowing through the load coil L. Therefore, when the value of the flowing current is large, the flyback voltage sometimes exceeds the power supply voltage, and this voltage is directly applied to each current source. It may be damaged.

Therefore, in order to protect each current source from the above flyback voltage, a conventional method is to add a protection diode and a damping circuit.
A circuit in which a protection diode and a damping circuit are added to the H-type drive circuit shown in FIG. 14 will be described with reference to FIG.

The H-type drive circuit shown in FIG. 15 has the configuration of the H-type drive circuit shown in FIG.
Bypassing the current due to the positive flyback voltage generated at the output terminal connected to the series circuit of the current source 3,
A protection diode 37 for protecting the current source 1, and a second
A protection diode 38 for protecting the second current source 2 by bypassing the current due to the positive flyback voltage generated at the output terminal connected to the series circuit of the current source 2 and the fourth current source 4; A protection diode 39 for protecting the third current source 3 by bypassing the current due to the negative flyback voltage generated at the output terminal connected to the series circuit of the current source 1 and the third current source 3; A protection diode 40 for protecting the fourth current source 4 by bypassing the current due to the negative flyback voltage generated at the output terminal connected to the series circuit of the current source 2 and the fourth current source 4, and a load coil. It is configured by adding a damping circuit D for shaping the current waveform of L and suppressing the flyback voltage.

Conventionally, these protection diodes 37 and 3 are provided.
The components of each current source are protected by using 8, 39 and 40 to bypass the current due to the excessive flyback voltage and suppressing the flyback voltage by using the damping circuit D.

By the way, one of the characteristics required for a coil used in a motor or a coil used in a data writing head of a magnetic disk device is a current flowing through the coil when the direction of the current is changed. It is possible to stand up at a high speed. That is, when the direction of the current flowing through the coil is switched, the current of a predetermined value must start flowing with good followability to the switching operation.

Since the value of the current flowing through the coil increases in proportion to the value of the voltage applied to the coil,
The larger the value of the voltage applied to the coil, the larger the value of the current flowing through the coil, and reaches a predetermined value in a short time.

Therefore, the larger the value of the flyback voltage applied to the load coil L at the moment when the direction of the current flowing through the load coil L is switched, the more responsive the drive current starts to flow.

[0017]

However, in the conventional H-type drive circuit with a protection circuit (see FIG. 15), as described above, the protection diodes 37, 38, 39 and 40 are provided.
Moreover, the flyback voltage is suppressed by the action of the damping circuit D. Therefore, there is a problem that it takes a long time for the current to reach a predetermined value, and the high-speed response to the switching of the current direction deteriorates.

An object of the present invention is to prevent damage and malfunction of current source components due to excessive flyback voltage,
An object of the present invention is to provide an H-type drive circuit having a characteristic that a current flowing through a load coil reaches a predetermined value in a short time when switching its direction.

[0019]

In order to solve the above-mentioned problems, the invention as set forth in claim 1, as shown in FIG. 1, is provided between a high potential side power source V _CC and a low potential side power source V _SS. Is connected to a series circuit composed of a first current source 1 and a third current source 3 whose conduction is controllable, and a series circuit composed of a second current source 2 and a fourth current source 4 whose conduction is controllable, respectively. A connection point between the first current source 1 and the third current source 3;
A load is connectable between a connection point between the current source 2 and the fourth current source 4, and the first current source 1 and the fourth current source 4 are connected.
And a drive circuit capable of reversibly controlling the direction of the current flowing through the load by controlling conduction between the second current source 2 and the third current source 3 in antiphase relationship with each other. A first rectifying element 5 is inserted in the forward direction between the first current source 1 and a connection point of the first current source 1 and the third current source 3 in a series circuit of the current source 1 and the third current source 3. And the second current source 2 in the series circuit of the second current source 2 and the fourth current source 4, and the second current source 2 and the fourth current source 4.
The second rectifying element 6 is characterized in that it is inserted in the forward direction between the connection point of the current source 4 and the connection point.

The invention according to claim 2 is, for example, as shown in FIG. 3, in the drive circuit according to claim 1, the low potential side terminal of the third current source 13 and the low potential side terminal of the fourth current source 14 are low. The potential side terminal is connected, and the first constant current source 19 is inserted between the connection point and the low potential side power source V _SS .

According to a third aspect of the present invention, for example, as shown in FIG. 4, in the drive circuit according to the first aspect, the first current source 11, the first rectifying element 15 and the third current source 13 are connected in series. The third rectifying element 17 is provided between the connection point between the first rectifying element 15 and the third current source 13 in the circuit and the third current source 13.
Is inserted in the forward direction, the connection point between the second rectifying element 16 and the fourth current source 14 in the series circuit of the second current source 12, the second rectifying element 16 and the fourth current source 14, and the fourth current source. The fourth rectifying element 18 is inserted between 14 in the forward direction.

The invention described in claim 4 is, for example, as shown in FIG. 5, in the drive circuit according to claim 3, the low potential side terminal of the third current source 13 and the low potential side terminal of the fourth current source 14 are low. The potential side terminal is connected, and the first constant current source 19 is inserted between the connection point and the low potential side power source V _SS .

According to a fifth aspect of the present invention, for example, as shown in FIG. 6, in the drive circuit according to the first aspect, the first circuit is provided between the high potential side power source V _CC and the low potential side power source V _SS . Resistance R ₁
And a series circuit including a first signal inversion circuit 21 capable of controlling conduction, and a series circuit including a second resistor R ₂ and a second signal inversion circuit 22 capable of controlling conduction are connected to each other, and the first resistor R 2 is connected.
_At the connection point between ₁ and the first signal inversion circuit 21, the first current source 1
1 control terminal is connected, the control terminal of the first signal inverting circuit 21 is connected to the control terminal of the third current source 13,
The control terminal of the second current source 12 is connected to the connection point between the second resistor R ₂ and the second signal inverting circuit 22, and the control terminal of the second signal inverting circuit 22 is the control terminal of the fourth current source 14. It is configured to be connected to.

According to a sixth aspect of the present invention, as shown in FIG. 7, for example, in the drive circuit according to the fifth aspect, the low potential side terminal of the third current source 13 and the low potential side terminal of the fourth current source 14 are low. The potential side terminal is connected, the first constant current source 19 is inserted between the connection point and the low potential side power source V _SS, and the low potential side terminal of the first signal inverting circuit 21 and the second signal inversion circuit The low potential side terminal of the circuit 22 is connected, and the second constant current source 20 is inserted between the connection point and the low potential side power supply V _SS .

According to a seventh aspect of the present invention, as shown in FIG. 10, for example, in the drive circuit according to the fifth aspect, the first current source 11, the first rectifying element 15, and the third current source 13 are provided.
First rectifying element 15 and third current source 13 in the series circuit of
The third rectifying element 1 between the connection point of the
7 is inserted in the forward direction, the connection point between the second rectifying element 16 and the fourth current source 14 in the series circuit of the second current source 12, the second rectifying element 16 and the fourth current source 14, and the fourth current. A fourth rectifying element 18 is inserted between the sources 14 in the forward direction.

According to an eighth aspect of the invention, for example, as shown in FIG. 11, in the drive circuit according to the seventh aspect, the low potential side terminal of the third current source 13 and the low potential side terminal of the fourth current source 14 are low. The potential side terminal is connected, and the first constant current source 19 is inserted between the connection point and the low potential side power source V _SS ,
The low potential side terminal of the signal inverting circuit 21 and the low potential side terminal of the second signal inverting circuit 22 are connected, and the second constant current source 20 is inserted between the connection point and the low potential side power supply V _SS. It is characterized by that.

[0027]

According to the invention described in claim 1, as shown in FIG.
The flybar generated at the moment when the direction of the current was switched.
Voltage to V_FB, Flyback voltage V_FBIs the first rectifying element
5 and a series circuit including the first current source 1
The voltage across the first rectifying element 5 and the voltage across the first current source 1
Voltage is V_D5And V₁Then, V_FB= V _D5+ V
₁And V_D5Is V₁Large enough for
To prevent the flyback voltage from being applied to the first current source 1.
Stop.

Similarly, when the flyback voltage V _FB is applied to the series circuit including the second rectifying element and the second current source 2, the voltage 6 across the second rectifying element 6 and the both ends of the second current source 2 are applied. Let the voltages of V _D6 and V ₂ respectively be V _FB = V _D6
+ V ₂ and V _D6 is sufficiently larger than V ₂ ,
The excessive flyback voltage is prevented from being applied to the second current source 2.

Therefore, an excessive flyback voltage V _FB
Can be prevented from being applied to the first current source 1 and the second current source 2, so that the first current source 1 and the second current source 2 can be prevented.
Furthermore, since the flyback voltage V _FB is not suppressed, the current can reach a predetermined value in a short time when the direction of the current flowing through the load is switched.

According to the invention described in claim 2, for example, as shown in FIG. 3, in addition to the operation similar to that of the invention described in claim 1, the first constant current source 19 includes the high potential side power source V. _The amount of current flowing from _CC to the low-potential-side power supply V _SS via the circuit according to claim 1 is maintained at a constant value.

Therefore, in addition to the same effect as the invention described in claim 1, at the moment when the direction of the current flowing through the load is switched, the high-potential-side power source V _CC changes to the first current source 11,
A through current that flows to the low potential side power source V _SS via the first rectifying element 15 and the third current source 13, and a second current source 12, a second rectifying element 16 and a fourth current source 14 from the high potential side power source V _CC .
Through current can be prevented from flowing to the low-potential-side power supply V _SS via the first potential source 11, the third current source 13, and the second current source 11.
The current source 12 and the fourth current source 14 can be protected.

Further, by controlling the value of the current flowing through the first constant current source 19, the value of the drive current flowing through the load can be easily controlled. Furthermore, since the third current source 13, the fourth current source 14, and the first constant current source 19 form a differential pair, the third current source 13 and the fourth current source 14
The switching operation can be performed reliably and at high speed.

According to the invention described in claim 3, for example, as shown in FIG. 4, in addition to the same operation as that of the invention described in claim 1, the flyback voltage is the third rectifying element 17 and the third rectifier element.
When the voltage across the third rectifying element 17 and the voltage across the third current source 13 when applied to the series circuit including the current source 13 are V _D17 and V ₁₃ , respectively, V _D17 is relative to V ₁₃ . Since it is large enough, an excessive flyback voltage
It is prevented from being applied to the current source 13.

Similarly, the voltage across the fourth rectifying element 18 and the fourth current source 14 when the flyback voltage is applied to the series circuit including the fourth rectifying element 18 and the fourth current source 14.
Let V _D18 and V ₁₄ be the voltages at both ends of V
_D18 is sufficiently large with respect to V ₁₄ to prevent an excessive flyback voltage from being applied to the fourth current source 14.

Therefore, in addition to the effect similar to that of the invention described in claim 1, it is possible to prevent an excessive flyback voltage from being applied to the third current source 13 and the fourth current source 14. Since the third current source 13 and the fourth current source 14 can be protected and the flyback voltage is not suppressed, the switching of the direction of the current flowing through the load
The current can reach a predetermined value in a short time.

According to the invention described in claim 4, for example, as shown in FIG. 5, in addition to the same operation as that of the invention described in claim 3, the first constant current source 19 includes the high-potential-side power source V. _The amount of current flowing from _CC to the low potential side power supply V _SS via the circuit according to claim 3 is kept at a constant value.

Therefore, in addition to the effect of the invention described in claim 3, the same effect as the invention described in claim 2 can be obtained. That is, the first current source 11, the second current source 12, and the third current source 13 are detected from the excessive flyback voltage and shoot-through current.
Also, while protecting the fourth current source 14, the current can reach a predetermined value in a short time when the direction of the current flowing through the load is switched, and the value of the drive current flowing through the load can be easily controlled. Therefore, the third current source 13 and the fourth current source 14 can be reliably and rapidly switched.

According to the invention described in claim 5, for example, as shown in FIG. 6, in addition to the operation of the invention described in claim 1, the first signal inverting circuit 21 and the second signal inverting circuit 22 are provided.
Generates an inverted signal of the control signal input from each control terminal, and outputs the first current source 11 and the second current source 1 respectively.
Output to 2.

The first resistor R ₁ gives a bias voltage for driving the first current source 11. The second resistor R ₂ is the second
A bias voltage for driving the current source 12 is provided. Therefore, in addition to the effect similar to that of the invention described in claim 1, the first current source 11 and the third current source 13 which operate in anti-phase are controlled by one control signal, and similarly Since the second current source 12 and the fourth current source 14 that operate can be controlled by one control signal, the number of terminals for input can be reduced, the entire circuit can be miniaturized, and the first current source 11 and the third current source 3
The current source 13, the second current source 12, and the fourth current source 14 can be operated simply and reliably in the antiphase relationship.

According to the invention described in claim 6, for example, as shown in FIG. 7, in addition to the operation described in claim 5, the first
The constant current source 19 includes the high-potential-side power source V _CC and the first current source 1
The amount of current flowing to the low-potential-side power supply V _SS via the circuit including the first, second current source 12, the first rectifying element 15, the second rectifying element 16, the load, the third current source 13, and the fourth current source 14 Keep it at a constant value.

Therefore, in addition to the effect of the invention described in claim 5, the same effect as the invention described in claim 2 can be obtained. That is, while protecting the first current source 11 and the second current source 12 from the flyback voltage, the drive current flowing through the load is made to reach a predetermined value in a short time, and the circuit is downsized so that the first current source 11 In addition to the effect of operating the second current source 12 and the third current source 13 and the fourth current source 14 in a simple and reliable reverse phase relationship, the first current source 11 and the third current source 13 Second current source 12 and fourth
The current source 14 can be protected, the value of the drive current flowing through the load can be easily controlled, and the third current source 13 and the fourth current source 14 can be reliably and rapidly switched.

Further, the second constant current source 20 has the amount of current flowing from the high potential side power source V _CC to the low potential side power source V _SS via the first resistor R ₁ and the first signal inverting circuit 21, and the high potential side. Power supply V
_The amount of current flowing from _CC to the low-potential-side power supply V _SS via the second resistor R ₂ and the second signal inverting circuit 22 is kept at a constant value.

Therefore, in addition to the effect of the invention described in claim 5, the first signal inverting circuit 21 and the second signal inverting circuit 2 are provided.
Since a differential pair is formed by the second and second constant current sources 20, the first signal inversion circuit 21 and the second signal inversion circuit 22 are applied to the respective signal inversion circuits in order to perform a switching operation in a completely opposite phase. The bias voltage is applied to the third current source 13
And can be set independently of the fourth current source 14,
It is possible to easily control the anti-phase switching operation.

According to the invention described in claim 7, for example, as shown in FIG. 10, in addition to the function of the invention described in claim 5, the flyback voltage is the third rectifying element 17 and the third current source 13. the voltage across the third rectifying element 17 and the third current source 13 when it is applied to the series circuit each V _D17 including
And V ₁₃ , V _D17 is sufficiently larger than V ₁₃ to prevent an excessive flyback voltage from being applied to the third current source 13.

Similarly, the voltage across the fourth rectifying element 18 and the fourth current source 14 when the flyback voltage is applied to the series circuit including the fourth rectifying element 18 and the fourth current source 14 is V _D18 , respectively. And V ₁₄ , V _D18 is sufficiently large with respect to V ₁₄ , so that an excessive flyback voltage becomes the fourth
It is prevented from being applied to the current source 14.

Therefore, in addition to the same effect as the invention described in claim 5, the same effect as the invention described in claim 3 is achieved. That is, the circuit is miniaturized, and the first current source 11 and the second current source 12, and the third current source 13 and the fourth current source 14 are formed.
In addition to the effect of simply and reliably operating in a reverse phase relationship, the first current source 11, the second current source 12, the third current source 13, and the fourth current source 14 can be protected from the flyback voltage. In addition, the current can reach a predetermined value in a short time when the direction of the current flowing through the load is switched.

According to the invention described in claim 8, for example, as shown in FIG. 11, in addition to the operation described in claim 7, the first constant current source 19 includes the first constant current source V _CC from the high potential side power source V _CC . Current source 1
1, a second current source 12, a first rectifying element 15, a second rectifying element 16, a load, a third rectifying element 17, a fourth rectifying element 18, a third current source 13 and a circuit including a fourth current source 14 The amount of current flowing through the low-potential-side power supply V _SS is kept constant.

Therefore, in addition to the effect of the invention described in claim 7, the effect of the invention described in claim 2, that is, from the through current flowing at the moment when the direction of the current flowing to the load is switched to the first current source 11 and The third current source 13, the second current source 12, and the fourth current source 14 can be protected, and the value of the drive current flowing through the load can be easily controlled. The source 14 can be reliably and rapidly switched.

The second constant current source 20 has the amount of current flowing from the high potential side power source V _CC to the low potential side power source V _SS via the first resistor R ₁ and the first signal inverting circuit 21, and the high potential side. Power supply V
_The amount of current flowing from _CC to the low-potential-side power supply V _SS via the second resistor R ₂ and the second signal inverting circuit 22 is kept at a constant value.

Therefore, in addition to the effect of the invention described in claim 7, the first signal inverting circuit 21 and the second signal inverting circuit 2 are provided.
The bias voltage applied to each of the signal inversion circuits in order to perform the switching operation of 2 in the completely opposite phase can be set independently of the third current source 13 and the fourth current source 14, and the opposite phase can be easily provided. It is possible to control various switching operations.

[0051]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments of the present invention will be described with reference to the drawings. (I) First Embodiment FIG. 2 shows an embodiment of an H-type drive circuit corresponding to the invention described in claim 1.

As shown in FIG. 2, in the first embodiment, the current source transistor 11, the Schottky diode 15, and the current source transistor 13 are connected between the high potential side power source V _CC and the low potential side power source V _SS. A series circuit consisting of
A series circuit including a current source transistor 12, a Schottky diode 16 and a current source transistor 14 is connected in parallel with the series circuit, and the Schottky diode 1
One of the load terminals is derived from the connection point between the cathode terminal of 5 and the collector terminal of the current source transistor 13, and the other of the load terminals is connected from the connection point of the cathode terminal of the Schottky diode 16 and the collector terminal of the current source transistor 14. It is derived and a so-called H-type drive circuit is formed. The load coil L is connected to this load terminal.

Further, the current source transistors 11, 12, 1
Npn type bipolar transistors are used for 3 and 14, respectively. Next, the operation will be described.

When driving the load coil L, the current source transistor 11 and the current source transistor 14 are paired, and the current source transistor 12 and the current source transistor 13 are paired, and each pair is alternately turned on / off.

That is, the base of the current source transistor 11 is
Terminal T_i1And the base terminal T of the current source transistor 14_i4
Control signal C₁The current source transistor 12
Terminal T_i2And the base terminal T of the current source transistor 13_i3
Control signal C₁Control signal C opposite in phase to₂give. So
As a result, the current source transistor 11 and the current source transistor
14 turns on at the same time, and at this time, the current source transition
Circuit 12 and current source transistor 13 are turned off.
Drive current I in the direction indicated by the solid arrow in FIG.₁Flows
It On the other hand, the current source transistor 11 and the current source transistor
Current source transistor 12 and current source transistor
When the transistor 13 is turned on, the broken line arrow in FIG.
Drive current I in the direction shown₂Flows. Thus, the control signal
Issue C₁And C ₂By alternately switching the polarities of
A drive current flows through the load coil L to drive the load coil L.
can do.

In the first embodiment, an excessive flyback voltage is generated in the load coil at the moment when the direction of the drive current flowing in the load coil L is switched. At this time, the flyback voltage is applied to a series circuit including the current source transistor 11 and the Schottky diode 15 or a series circuit including the current source transistor 12 and the Schottky diode 16. Here, the voltage applied to the current source transistor 11 or 12 when the flyback voltage is applied is V ₁ or V _2, and the voltage applied to the Schottky diode 15 or 16 is V _D5 or V _D6 , respectively. Then, V _D5 >> V ₁ and V _D6 >> V ₂ .

Therefore, according to the first embodiment, even if an excessive flyback voltage is generated, the excessive voltage is not applied to the current source transistor 11 or 12, so the current source transistor 11 or 12 should be protected. You can

[0058] Further, the driving current I _O (t), the voltage applied across the load coil L E, an inductance component of the load coil L l, and the resistance component of the load coil L and r, simplified In the transient response of the integrating circuit including the resistor and the coil, the relationship of the following expression (1) is generally established.

[0059] _{I O (t) = (E} / r) {1-exp ((- r / l) · t)} ... (1) Therefore, the equation (1), the larger the E I _O (t) Therefore, the driving current reaches a predetermined current value in a shorter time as the voltage applied across the load coil L increases.

Here, in the first embodiment, the flyback voltage is applied to the load coil L by being superimposed on the voltage that starts to be applied to both ends of the load coil L from the moment when the direction of the drive current is switched. Since the voltage E in (1) increases, an increase in drive current is promoted.

Therefore, according to the first embodiment, unlike the prior art, the flyback voltage is not suppressed for protection of the current source transistor, so that the drive current can be changed in a short time for switching the current direction. It is possible to reach a predetermined value. (II) Second Embodiment FIG. 3 shows an embodiment corresponding to the invention described in claim 2.
In FIG. 3, the same parts as those in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted.

In the second embodiment, a constant current source transistor 19 is added to the circuit shown in the first embodiment to keep the amount of current flowing in the circuit shown in the first embodiment at a constant value. As shown in FIG. 3, in the second embodiment, in addition to the H-type drive circuit shown in the first embodiment, the emitter terminal of the current source transistor 13 and the emitter terminal of the current source transistor 14 are connected, and the connection is made. Point and low potential side power supply V _SS
And a constant current source 19 between them.

Next, the operation will be described. Since the base voltage of the constant current source transistor 19 in the second embodiment is constant, the amount of current flowing from the high potential side power supply V _CC to the low potential side power supply V _SS via the circuit shown in the first embodiment. Is kept constant.

Therefore, at the moment when the direction of the current flowing through the load coil L is switched, the high potential side power source V _CC
The current source transistor 11, the Schottky diode 15 and the current source transistor 13 which are connected in series between the low potential side power supply V _SS and the current source transistor 12, the Schottky diode 16 and the current source transistor 14. Since a through current can be prevented from flowing in the path including the current source transistor 11, the current source transistor 13, the current source transistor 12, and the current source transistor 14, can be protected.

Since the current source transistors 13 and 14 and the constant current source transistor 19 form a differential pair, the switching operation of the current source transistors 13 and 14 can be performed reliably and at high speed.

In the second embodiment, the constant current source transistor 19 is arranged between the connection point between the emitter terminal of the current source transistor 13 and the emitter terminal of the current source transistor 14 and the low potential side power source V _SS. Although connected, the collector terminal of the current source transistor 11 and the current source transistor 1
It may be connected between the connection point of the second collector terminal and the high-potential-side power supply V _CC . In this case, the current source transistors 11 and 12 and the constant current source transistor 19 are pn
It is replaced with a p-type bipolar transistor. (III) Third Embodiment FIG. 4 shows an embodiment corresponding to the invention described in claim 3.
4, the same parts as those in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted.

In the third embodiment, Schottky diodes 17 and 18 are added to the circuit shown in the first embodiment, and the current source transistor 13 and the current source transistor 1 are added.
It was prevented that an excessive flyback voltage was applied to No. 4.

As shown in FIG. 4, in the third embodiment, in addition to the H-type drive circuit shown in the first embodiment, a current source transistor 11, a Schottky diode 15 and a current source transistor 13 are connected in series. A connection point between the Schottky diode 15 and the current source transistor 13,
A Schottky diode 17 is connected in the forward direction between the current source transistors 13, and the current source transistor 12, the Schottky diode 16 and the current source transistor 14 are connected.
Connection point of the Schottky diode 16 and the current source transistor 14 in the series circuit of
4, a Schottky diode 18 is connected in the forward direction.

Next, the operation will be described. In the third embodiment, an excessive flyback voltage is generated in the load coil at the moment when the direction of the drive current flowing in the load coil L is switched. At this time, the flyback voltage is applied to a series circuit including the current source transistor 13 and the Schottky diode 17 or a series circuit including the current source transistor 14 and the Schottky diode 18. here,
The voltage applied to the current source transistor 13 or 14 when the flyback voltage is applied is V ₁₃ or V, respectively.
₁₄ , and the voltage applied to the Schottky diode 17 or 18 is V _D17 or V _D18 , respectively, V _D17 >> V
₁₃ and V _D18 >> V ₁₄ .

Therefore, according to the third embodiment, even if an excessive flyback voltage is generated, the excessive voltage is not applied to the current source transistor 13 or 14, so the current source transistor 13 or 14 should be protected. You can

Further, as in the first embodiment, the flyback voltage superimposes the voltage applied to the load coil L when the direction of the drive current is switched, so that the drive current is increased and the drive current is increased. Can reach a predetermined value in a short time.

Further, since the potentials of the collector terminals of the current source transistors 13 and 14 do not drop excessively, it is possible to prevent a reverse current from flowing from the substrate of the current source transistors 13 and 14 to the collector terminals. You can

Further, since the current source transistor 13 and the current source transistor 14 can be operated in the active region, the on / off switching can be performed at high speed. (IV) Fourth Embodiment FIG. 5 shows an embodiment corresponding to the invention described in claim 4.
5, the same parts as those in FIG. 4 are designated by the same reference numerals, and detailed description thereof will be omitted.

In the fourth embodiment, the constant current source transistor 19 shown in the second embodiment is added to the circuit shown in the third embodiment in the same manner as in the second embodiment. The operation and effect of the constant current source transistor 19 in the fourth embodiment are the same as those in the second embodiment, so the description thereof will be omitted.

In the fourth embodiment, the constant current source transistor 19 is provided between the connection point between the emitter terminal of the current source transistor 13 and the emitter terminal of the current source transistor 14 and the low potential side power source V _SS. Although connected, the collector terminal of the current source transistor 11 and the current source transistor 1
It may be connected between the connection point of the second collector terminal and the high-potential-side power supply V _CC . In this case, the current source transistors 11 and 12 and the constant current source transistor 19 are pn
It is replaced with a p-type bipolar transistor. (V) Fifth Embodiment FIG. 6 shows an embodiment corresponding to the invention described in claim 5.
In FIG. 6, the same parts as those in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted.

In the fifth embodiment, the signal inverting transistors 21 and 22 are added to the circuit shown in the first embodiment.
And resistors R ₁ and R ₂ are added. As shown in FIG. 6, in addition to the H-type drive circuit shown in the first embodiment, the fifth embodiment has a high potential side power supply V _CC and a low potential side power supply V _CC.
A series circuit composed of the resistor R ₁ and the signal inversion transistor 21 is connected in parallel with the circuit shown in the first embodiment between the _SS and the resistor R ₂ and the signal inversion transistor 22 in parallel with these circuits. Connected in series circuit.

At the connection point between the resistor R ₁ and the signal inversion transistor 21, the base terminal T of the current source transistor 11 is connected.
_i1 is connected, and the base terminal T _i2 of the current source transistor 12 is connected to the connection point of the resistor R ₂ and the signal inversion transistor 22.

Further, the base terminal of the signal inversion transistor 21 and the base terminal T _i3 of the current source transistor 13 are connected, and the base terminal of the signal inversion transistor 22 and the base terminal T _i4 of the current source transistor 14 are connected.

The signal inversion transistors 21 and 22 include
An npn-type bipolar transistor is used for each. Next, the operation will be described.

When the control signal C ₂ for turning on the current source transistor 13 is input to the base terminal T _i3 of the current source transistor 13, the signal inversion transistor 21 is turned on, and the high potential side power supply V _CC is turned on. A current flows through the resistor R ₁ and the signal inversion transistor 21 to the low potential side power source V _SS . Therefore, the potential of the base terminal T _i1 of the current source transistor 11 becomes lower than the potential of the high potential side power source V _{CC by} the voltage drop in the resistor R _{1, and} the current source transistor 11 is turned off. As a result, the control signal C
_{Due to 2} , the current source transistor 11 is turned off and the current source transistor 13 is turned on. That is, the current source transistor 11 and the current source transistor 13
Are controlled in an opposite phase relationship by a control signal C ₂ .

When the control signal C ₁ for turning on the current source transistor 14 is input to the base terminal T _i4 of the current source transistor 14, the current source transistor is operated by the same operation as described above. 12 is turned off, and the current source transistor 14 is turned on. That is, the current source transistor 12 and the current source transistor 14 are controlled by the control signal C _{1 so} as to have an opposite phase relationship.

Here, the control signal C ₁ and the control signal C ₂ are
As described in the first embodiment, the signals are input in a reverse phase relationship with each other. As a result of the above operation, the control signal C ₁ and the control signal C _2
Are input to the base terminal T _i3 and the base terminal T _i4 in an opposite phase relationship, the circuit shown in the fifth embodiment operates in the same manner as the drive circuit shown in the first embodiment.

Therefore, since the number of terminals for inputting the control signal is only two, the number of terminals for inputting the control signal can be reduced, and the entire circuit can be downsized as compared with the first embodiment, and the reverse The current source transistors 11 and 13 and the current source transistors 12 and 14 which should operate in a phase relationship can be operated simply and reliably in the opposite phase. (VI) Sixth Embodiment FIG. 7 shows an embodiment corresponding to the invention described in claim 6.
In FIG. 7, the same parts as those in FIG. 6 are designated by the same reference numerals, and detailed description thereof will be omitted.

In the sixth embodiment, a constant current source transistor 20 is added to the circuit obtained by combining the fifth embodiment shown in FIG. 6 and the second embodiment shown in FIG.
And 22 to form a differential pair so that a bias voltage for surely operating the signal inversion transistors 21 and 22 in a reverse phase can be applied.

As shown in FIG. 7, in the sixth embodiment, in addition to the H-type drive circuit shown in the fifth embodiment, the emitter terminal of the current source transistor 13 and the emitter terminal of the current source transistor 14 are connected. The constant current source 19 is connected between the connection point and the low potential side power supply V _SS , the emitter terminal of the signal inversion transistor 21 and the emitter terminal of the signal inversion transistor 22 are connected, and the connection point and the low potential side power supply are connected. A constant current source 20 is connected to V _SS .

Next, the operation will be described. The operation and effect of the constant current source transistor 19 in the sixth embodiment are the same as those in the second embodiment.
The description is omitted because it is similar to the embodiment.

The constant current source transistor 20 includes a current flowing from the high potential side power source V _CC to the low potential side power source V _SS via the resistor R ₁ and the signal inverting transistor 21, and the high potential side power source V _CC.
The value of the current that flows from _CC to the low-potential-side power supply V _SS via the resistor R ₂ and the signal inversion transistor 22 is held at a constant value.

Therefore, since the constant current source transistor 20 and the signal inversion transistors 21 and 22 form a differential pair independently of the constant current source transistors 13 and 14, the signal inversion transistors 21 and 22 are completely reversed in phase. The bias voltage for operation can be easily set.

In the sixth embodiment, the constant current source transistor 19 is provided between the connection point between the emitter terminal of the current source transistor 13 and the emitter terminal of the current source transistor 14 and the low potential side power source V _SS. Although connected, the collector terminal of the current source transistor 11 and the current source transistor 1
It may be connected between the connection point of the second collector terminal and the high-potential-side power supply V _CC . In addition, the constant current source transistor 20
Is connected between the connection point between the emitter terminal of the signal inversion transistor 21 and the emitter terminal of the signal inversion transistor 22 and the low potential side power supply V _SS , which is connected to the high potential side power supply V _CC.
You may connect to the side. An example of the circuit configuration in the above case is shown in FIG.
And shown in FIG.

In the circuit of FIG. 8, the current source transistors 11 and 12 and the constant current sources 19 and 20 are replaced by pnp type bipolar transistors. In the circuit of FIG. 9, the current source transistors 11 and 12 and the constant current source are constant current. Source transistors 19 and 20 and signal inversion transistors 21 and 22 have been replaced by pnp type bipolar transistors. (VII) Seventh Embodiment FIG. 10 shows an embodiment corresponding to the invention described in claim 7. In FIG. 10, the same parts as those in FIG. 6 are designated by the same reference numerals, and detailed description thereof will be omitted.

The seventh embodiment is a combination of the fifth embodiment shown in FIG. 6 and the third embodiment shown in FIG. Figure 10
As shown in FIG. 7, in the seventh embodiment, in addition to the H-type drive circuit shown in the fifth embodiment, the Schottky diode 17 and the Schottky diode 18 shown in the third embodiment are added to the third embodiment. It is added in the same manner as.

The operations and effects of the Schottky diode 17 and the Schottky diode 18 in the seventh embodiment are the same as those in the third embodiment shown in FIG. (VIII) Eighth Embodiment FIG. 11 shows an embodiment corresponding to the invention described in claim 8. 11, the same parts as those in FIG. 10 are designated by the same reference numerals, and detailed description thereof will be omitted.

The eighth embodiment is a combination of the seventh embodiment shown in FIG. 10 and the sixth embodiment shown in FIG. As shown in FIG. 11, the eighth embodiment includes constant current sources 19 and 20 with the same configuration as the sixth embodiment, in addition to the H-type drive circuit shown in the seventh embodiment. .

Constant current sources 19 and 20 in the eighth embodiment
Since the operation and effect of the above are the same as those of the sixth embodiment shown in FIG. 7, description thereof will be omitted. In the eighth embodiment, the constant current source transistor 19 is connected between the connection point between the emitter terminal of the current source transistor 13 and the emitter terminal of the current source transistor 14 and the low potential side power source V _SS. It may be connected between the connection point of the collector terminal of the current source transistor 11 and the collector terminal of the current source transistor 12 and the high potential side power supply V _CC . Further, the constant current source transistor 20 is connected between the connection point between the emitter terminal of the signal inversion transistor 21 and the emitter terminal of the signal inversion transistor 22 and the low potential side power source V _SS , but this is connected to the high potential side power source V _CC. You may connect to the side. The circuit configuration in the above case is shown in FIGS.

In the circuit of FIG. 12, the current source transistors 11 and 12 and the constant current sources 19 and 20 are pnp.
13, the current source transistors 11 and 12, the constant current source transistors 19 and 20, and the signal inversion transistors 21 and 22 are replaced with pnp bipolar transistors. (IX) Other Examples In each of the examples described above, the example using the Schottky diode as the rectifying element has been described.
Instead of the Schottky diode, a PN junction diode having a high breakdown voltage can be used.

Further, as the diode, a diode-connected transistor can be used. In that case, if the drive circuit of each embodiment is manufactured by using semiconductor integrated circuit technology, the same process as that of each current source transistor can be performed. Since it can be manufactured, complication of the manufacturing process can be prevented.

[0097]

As described above, according to the invention described in claim 1, since the first rectifying element 5 and the second rectifying element 6 are added, an excessive flyback voltage is generated in the first current source 1 and Since it can be prevented from being applied to the second current source 2, the first current source 1 and the second current source 2 can be protected,
Further, since the flyback voltage is not suppressed, the drive current of the load can reach the predetermined value in a short time.

According to the invention described in claim 2, by adding the first constant current source 19 to the circuit shown in FIG. 2, the effect of the invention described in claim 1, that is, from the flyback voltage to the first In addition to the effect that the drive current of the load reaches a predetermined value in a short time while protecting the current source 11 and the second current source 12, at the moment when the direction of the current flowing through the load is switched, the first current source 11, Since it is possible to prevent an excessive shoot-through current from flowing in the series circuit including the first rectifying element 15 and the third current source 13, or the series circuit including the second current source 12, the second rectifying element 16 and the fourth current source 14. , First current source 1
It is possible to protect the first and third current sources 13 and the second and fourth current sources 12 and 14.

By controlling the value of the current flowing through the first constant current source 19, it is possible to easily control the value of the drive current flowing through the load. Further, since the third current source 13, the fourth current source 14, and the first constant current source 19 form a differential pair, the third current source 13 and the fourth current source 1
4 can be operated reliably and at high speed.

According to the third aspect of the present invention, by adding the third rectifying element 17 and the fourth rectifying element 18 to the circuit of the first aspect, an excessive flyback voltage is generated in the third current source 13 and the third current source 13. Since it can be prevented from being applied to the fourth current source 14, the effect of the invention according to claim 1 is short, while protecting the first current source 11 and the second current source 12 from the flyback voltage. In addition to the effect that the drive current of the load reaches a predetermined value in time, the third current source 13 and the fourth current source 14 can be protected from the flyback voltage, and the flyback voltage can be suppressed. Since it does not exist, the drive current of the load can reach the predetermined value in a short time.

According to the invention of claim 4, claim 3
By adding the first constant current source 19 to the circuit shown in
In addition to the same effects as the invention according to claim 3, claim 2
The same effect as the invention described in (3) is achieved.

That is, the drive current of the load is made to reach a predetermined value in a short time while protecting the first current source 11, the second current source 12, the third current source 13 and the fourth current source 14 from the flyback voltage. In addition to the effect that it is possible to protect the first current source 11 and the third current source 13 and the second current source 12 and the fourth current source 14 from an excessive shoot-through current, The value can be easily controlled, and the third current source 13 and the fourth current source 14 can be reliably and rapidly switched.

According to the invention described in claim 5, the first signal inversion circuit 21, the first resistor R ₁ , the second signal inversion circuit 22 and the second resistor R ₂ are added to the circuit shown in claim 1. Can control the first current source 11 and the third current source 13 that operate in anti-phase with one signal (control signal C ₂ ), and the second current that also operates in anti-phase. Source 1
2 and the fourth current source 14 can be controlled by _one signal (control signal C ₁ ).

Therefore, the effect of the invention described in claim 1, that is, the drive current of the load can reach the predetermined value in a short time while protecting the first current source 1 and the second current source 2 from the flyback voltage. In addition to the effect that it is possible, the number of terminals for inputting a control signal is reduced, the entire circuit is downsized, and the first current source 11, the third current source 13, and the second current source 11
The current source 12 and the fourth current source 14 can be operated simply and reliably in the antiphase relationship.

According to the invention of claim 6, by adding the first constant current source 19 to the circuit of claim 5,
In addition to the same effects as the invention according to claim 5, claim 2
The same effect as the invention described in (3) is achieved.

That is, while protecting the first current source 11 and the second current source 12 from the flyback voltage, the drive current of the load reaches a predetermined value in a short time, and the circuit is miniaturized to In addition to the effect of operating the third current source 13 and the second current source 12 and the fourth current source 14 in a reverse phase relation simply and reliably, the first current source 11 and the third current source are prevented from excessive through current. 13 and second current source 1
The second and fourth current sources 14 can be protected, the value of the drive current flowing through the load can be easily controlled, and the third current source 13 and the fourth current source 14 can be reliably and rapidly switched. be able to.

Further, by adding the second constant current source 20 to the circuit described in claim 5, a differential pair is formed by the first signal inverting circuit 21, the second signal inverting circuit 22 and the second constant current source 20. Therefore, the same effect as the invention described in claim 5, that is, the drive current of the load reaches a predetermined value in a short time while protecting the first current source 11 and the second current source 2 from the flyback voltage. At the same time, in addition to the effect that the circuit is miniaturized and the first current source 11 and the third current source 13 and the second current source 12 and the fourth current source 14 are operated simply and surely in a reverse phase relationship, Signal inversion circuit 21 and second
The bias voltage of each signal inversion circuit for performing the switching operation of the signal inversion circuit 22 in a completely opposite phase,
It can be set independently of the third current source 13 and the fourth current source 14, and the anti-phase switching operation can be easily controlled.

According to the invention described in claim 7, by adding the third rectifying element 17 and the fourth rectifying element 18 to the circuit described in claim 5, the same effect as the invention described in claim 5 can be obtained. In addition, the same effect as the invention according to claim 3 is obtained.

That is, the circuit is downsized while protecting the first current source 11 and the second current source 12 from the flyback voltage, and the first current source 11 and the third current source 13 and the second current source 12 and the fourth current source are protected. In addition to the effect that the power source 14 can be operated in a simple and reliable reverse-phase relationship, the third current source 13 and the fourth current source 14 can be protected from an excessive flyback voltage. Therefore, the drive current of the load can reach the predetermined value in a short time.

According to the invention described in claim 8, by adding the first constant current source 19 and the second constant current source 20 to the circuit shown in claim 7, the same as in the invention described in claim 7, In addition to the effect, the same effect as the invention according to claim 6 is obtained.

That is, the drive current of the load reaches a predetermined value in a short time while protecting the first current source 11, the second current source 12, the third current source 13 and the fourth current source 14 from the flyback voltage. In addition, the circuit is downsized, and the first current source 11, the third current source 13, and the second current source 12
In addition to the effect that the fourth current source 14 and the fourth current source 14 can be operated simply and reliably in an antiphase relationship, the first current source 11 and the third current source 13 and the second current source 12 and It is possible to protect the fourth current source 14 and easily control the value of the drive current flowing through the load.
Also, the fourth current source 14 can be surely and rapidly switched.

Further, the bias voltage of each of the signal inversion circuits for completely complementary switching operation of the first signal inversion circuit 21 and the second signal inversion circuit 22 is set to the third value.
Can be set independently from the current source 13 and the fourth current source 14,
The complementary switching operation can be controlled easily.

[Brief description of drawings]

FIG. 1 is a diagram showing the principle of the present invention.

FIG. 2 is a diagram showing a first embodiment corresponding to the invention described in claim 1.

FIG. 3 is a diagram showing a second embodiment corresponding to the invention described in claim 2.

FIG. 4 is a diagram showing a third embodiment corresponding to the invention according to claim 3;

FIG. 5 is a diagram showing a fourth embodiment corresponding to the invention described in claim 4;

FIG. 6 is a diagram showing a fifth embodiment corresponding to the invention described in claim 5;

FIG. 7 is a diagram showing a sixth embodiment corresponding to the invention described in claim 6;

FIG. 8 is a diagram showing a first modification of the sixth embodiment.

FIG. 9 is a diagram showing a second modification of the sixth embodiment.

FIG. 10 is a diagram showing a seventh embodiment corresponding to the invention set forth in claim 7;

FIG. 11 is a diagram showing an eighth embodiment corresponding to the invention described in claim 8;

FIG. 12 is a diagram showing a first modification of the eighth embodiment.

FIG. 13 is a diagram showing a second modification of the eighth embodiment.

FIG. 14 is a diagram showing a conventional H-type drive circuit.

FIG. 15 is a diagram showing an H-type drive circuit with a protection circuit according to a conventional technique.

[Explanation of Codes] 1 ... First current source 2 ... Second current source 3 ... Third current source 4 ... Fourth current source 5 ... First rectifying element 6 ... Second rectifying element 11, 12, 13, 14 ... Current Source transistors 15, 16 ... Schottky diode 17 ... Third rectifying element (Schottky diode) 18 ... Fourth rectifying element (Schottky diode) 19 ... First constant current source (constant current source transistor) 20 ... Second constant current Source (constant current source transistor) 21 ... First signal inversion circuit (signal inversion transistor) 22 ... Second signal inversion circuit (signal inversion transistor) 37, 38, 39, 40 ... Protection diode V _CC ... High potential side power supply V _SS ... low-potential-side power supply T _i1 ... first control terminal (base terminal) T _i2 ... second control terminal (base terminal) T _i3 ... third control terminal (base terminal) T _i4 ... fourth control terminal (base terminal) I ₁ , I ₂ ... Driving current C ₁ , C ₂ ... Control signal L ... Load coil V _B1 , V _B2 ... Base power supply D ... Damping circuit

Claims (8)

[Claims] 1. A series comprising a first current source (1) and a third current source (3) capable of controlling conduction between a high potential side power source (V _CC ) and a low potential side power source (V _SS ). A circuit is connected to a series circuit including a second current source (2) and a fourth current source (4) capable of controlling conduction, and the first current source (1) and the third current source (3) are connected. A load is connectable between a connection point between the first current source (1) and the fourth current source (2), and a connection point between the second current source (2) and the fourth current source (4). By controlling conduction between the source (4) and the second current source (2) and the third current source (3) in antiphase relationship with each other, the direction of the current flowing through the load can be reversibly controlled. In the drive circuit, the first current source (1) and the first current source (1) in the series circuit of the first current source (1) and the third current source (3) A first rectifying element (5) is inserted in a forward direction between a connection point of the current source (1) and the third current source (3), and the second current source (2) and the fourth current source (4). A second rectifying element (6) is inserted in the forward direction between the second current source (2) and the connection point of the second current source (2) and the fourth current source (4) in the series circuit of. Drive circuit characterized in that. 2. The drive circuit according to claim 1, wherein the low potential side terminal of the third current source (13) and the low potential side terminal of the fourth current source (14) are connected, and the connection point is A first constant current source (19) between the low potential side power source (V _SS )
The drive circuit is characterized in that is inserted. 3. The drive circuit according to claim 1, wherein the first rectifying element (1) in the series circuit of the first current source (11), the first rectifying element (15) and the third current source (13).
5) and the connection point between the third current source (13) and the third current source (13), a third rectifying element (17) is inserted in the forward direction, and the second current source (12), The second rectifying element (1) in the series circuit of the two rectifying element (16) and the fourth current source (14)
6) A drive circuit, characterized in that a fourth rectifying element (18) is inserted in the forward direction between the connection point between the fourth current source (14) and the fourth current source (14). 4. The drive circuit according to claim 3, wherein the low potential side terminal of the third current source (13) and the low potential side terminal of the fourth current source (14) are connected to each other, and A first constant current source (19) between the low potential side power source (V _SS )
The drive circuit is characterized in that is inserted. 5. The drive circuit according to claim 1, wherein the high potential side power source (V_CC) And the power supply on the low potential side (V_SSBetween)
The first resistor (R₁) And the first signal inversion capable of controlling conduction
A series circuit including a circuit (21) and a second resistor (R ₂) And
And a second signal inversion circuit (22) capable of controlling conduction.
A column circuit is connected to the first resistor (R₁) And the first signal inversion circuit (21)
The control terminal of the first current source (11) is connected to the connection point, and the control terminal of the first signal inversion circuit (21) is connected to the third power source.
Is connected to the control terminal of the flow source (13), and is connected to the second resistor (R₂) And the second signal inversion circuit (22)
The control terminal of the second current source (12) is connected to the connection point, and the control terminal of the second signal inversion circuit (22) is connected to the fourth power source.
Characterized in that it is connected to the control terminal of the flow source (14)
Drive circuit. 6. The drive circuit according to claim 5, wherein the low potential side terminal of the third current source (13) and the low potential side terminal of the fourth current source (14) are connected, and the connection point is A first constant current source (19) between the low potential side power source (V _SS )
Is inserted, the low potential side terminal of the first signal inverting circuit (21) and the low potential side terminal of the second signal inverting circuit (22) are connected, and the connection point and the low potential side power supply (V _SS ). A drive circuit characterized in that a second constant current source (20) is inserted between and. 7. The drive circuit according to claim 5, wherein the first rectifying element (1) in the series circuit of the first current source (11), the first rectifying element (15) and the third current source (13).
5) and the connection point between the third current source (13) and the third current source (13), a third rectifying element (17) is inserted in the forward direction, and the second current source (12), The second rectifying element (1) in the series circuit of the two rectifying element (16) and the fourth current source (14)
6) A drive circuit, characterized in that a fourth rectifying element (18) is inserted in the forward direction between the connection point between the fourth current source (14) and the fourth current source (14). 8. The drive circuit according to claim 7, wherein the low potential side terminal of the third current source (13) and the low potential side terminal of the fourth current source (14) are connected to each other, and A first constant current source (19) between the low potential side power source (V _SS )
Is inserted, the low potential side terminal of the first signal inverting circuit (21) and the low potential side terminal of the second signal inverting circuit (22) are connected, and the connection point and the low potential side power supply (V _SS ). A drive circuit characterized in that a second constant current source (20) is inserted between and.