JP3227048B2 - Driver circuit for bidirectional connection transistor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switching type rectifier circuit and a driving circuit for a bidirectional connection transistor in a power supply or the like.

[0002]

2. Description of the Related Art FIG. 9 is a block diagram showing a conventional example of a driving circuit for a bidirectional connection transistor.

In this conventional example, the base drive currents of the transistors 1 and 4 utilize the collector currents fed back via current feedback transformers 2 and 5 connected to the respective collector terminals, and are proportional to the collector currents. The supplied base drive current. The base current supply circuits 3 and 6 generate a trigger current at the time of turn-on, and have a function of inverting the direction of the base current and turning off the transistor.

[0004]

According to the above conventional example,
There is a problem that a current feedback transformer equal to the number of transistors is required, which limits the miniaturization of the drive circuit.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a small and simple circuit for driving a bidirectional connection transistor.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention firstly comprises two transistors in which an anti-parallel diode is connected between an emitter and a collector and two transistors are connected in series between emitter terminals. In a driving circuit for supplying a driving current of the two transistors by feedback of a collector current to a direction switching element, an emitter terminal connecting the two transistors and an anode terminal connecting the two diodes And a current feedback transformer is inserted between them.

The present invention also relates to a two-way switch device in which two transistors each having an anti-parallel diode connected between an emitter and a collector are connected in series between collector terminals. In the drive circuit that supplies the drive current of
A current feedback transformer is inserted between the collector terminal connecting the two transistors and a cathode terminal connecting the two diodes.

[0008]

According to the present invention, since the above-described configuration is adopted, the current feedback transformer, which is conventionally required two, is omitted to one, and
The collector current of any transistor can be fed back.

[0009]

FIG. 1 is a block diagram of a first embodiment of the present invention. In FIG. 1, 1 and 4 are transistors, 2 is a current feedback transformer, 3 and 6 are base current supply circuits, 7 and 8 are diodes, 19 is an input terminal, and 20 is an output terminal. The input current I ₁ , the primary winding current I _{2 of} the current feedback transformer 2, the collector currents I ₃ ,
FIG. 2 shows the current waveforms of I ₄ and the diode currents I ₅ and I ₆ . In this embodiment, a current feedback transformer 2 is inserted between the emitter terminal of the transistor and the anode terminal of the diode, and the collector current is fed back to the base current supply circuit. Similar to the conventional example shown in FIG. 9, the base current supply circuits 3 and 6 generate a trigger current at the time of turn-on, and have a function of inverting the direction of the base current and turning off the transistor. As shown in FIG. 2, the transistors 1 and 4 do not conduct at the same time, so that the current fed back by the current feedback transformer 2 can be switched by the base current supply circuit to drive the transistors. That is, according to the first embodiment, it is possible to omit one current feedback transformer, which is conventionally required two, and to feed back the collector current of any transistor. In this embodiment, the transistor but is NPN type, in the case of using the PNP-type, the direction of the diode 7 and 8 in the opposite, by the polarity of the windings N ₂ of the current feedback transformer 2 in the opposite The same effect can be obtained.

FIG. 3 is a block diagram of a second embodiment, which is a specific circuit configuration of the first embodiment. In FIG.
Reference numerals 9, 10, 11, and 12 indicate switches, reference numerals 13 and 14 indicate drive transformers, reference numerals 15, 16, 17, and 18 indicate diodes, and other reference numerals indicate the same elements as those in FIG. The input current I ₁ , the primary winding current I _{2 of} the current feedback transformer 2, the collector currents I ₃ and I _{4 of the} transistors 1 and ₄ , the base drive currents I ₇ and I ₈ , and the diode currents I ₅ and I ₆ FIG. 4 shows the waveforms and the operating states of the switches 9 to 12. In the present embodiment, at time t ₁ , the switch 9 that has been turned on is turned off, the energy stored in the drive transformer 13 is supplied to the base of the transistor 1, and the base drive current I ₇ flows. The base drive current by I ₇ transistor 1 is turned on, starts to flow the collector current I _3. The collector current I ₃ is fed back to the base current supply circuit 3 via the current feedback transformer 2, from the secondary winding N _{2 of the} current feedback transformer ₂ to the diode 16 and the drive transformer 1.
A current flows through the path of the _third winding N ₃ and the switch 10, and the base drive current determined by the turns ratio of the windings N ₁ , N ₂ , N ₃ , and N ₅ continues to be supplied. Just prior to time t ₂ the input current I ₁ by the external condition is reversed and turning on the transistor 4 by switching the switches 11 and 12, the input current which has been flowing in the path from the transistor 1 to the diode 8, the time t ₂
To move to the path from the transistor 4 to the diode 7. Base drive current of the transistor 1, 0 just before the time t ₂
But it becomes, until the time t ₂ is in the ON state is maintained by the accumulated charge. Off of the transistor is turned on switch 9 and 11, by reversing the direction of the base drive current I _7, I _8, carried out by pulling out the accumulated charge, the input at time t ₃ when the transistor 4 is turned off current I ₁ Is shut off. That is, according to the second embodiment, the current feedback transformer, which is conventionally required two, can be omitted to one, and the collector current of any transistor can be fed back. In this embodiment, the transistor is of the NPN type.
When the PNP type is used, the directions of the diodes 7 and 8 are reversed, and the polarities of the winding N ₂ of the current feedback transformer 2 and the windings N ₅ and N ₈ of the driving transformers 13 and 14 are reversed. Similar effects can be obtained.

Next, FIG. 5 shows a configuration diagram of a third embodiment of the present invention. The present embodiment is an example of a drive circuit using a bidirectional switch element in which two transistors are connected between collector terminals, and the reference numerals in the drawing indicate the same as those in FIG. The input current I ₁ , the primary winding current I _{2 of} the current feedback transformer ₂ ,
FIG. 6 shows current waveforms of the collector currents I ₃ and I ₄ and the diode currents I ₅ and I ₆ of the transistors 1 and 4, respectively. In this embodiment, a current feedback transformer 2 is inserted between the collector terminal of the transistor and the cathode terminal of the diode, and the collector current is fed back to the base current supply circuit.
Similar to the conventional example shown in FIG. 9, the base current supply circuits 3 and 6 have a function of generating a trigger current at the time of turn-on and reversing the direction of the base current. Since the transistors 1 and 4 are not turned on at the same time, the current fed back by the current feedback transformer 2 can be switched by the base current supply circuit to drive the transistors. That is,
According to the third embodiment, two current feedback transformers, which are conventionally required, can be omitted to one, and the collector currents of any transistors can be fed back. In this embodiment, although the transistor is of NPN type, PNP
When using a mold, the direction of the diodes 7 and 8 is reversed,
By the polarity of the windings N ₂ of the current feedback transformer 2 Conversely, the same effect can be obtained.

FIG. 7 is a block diagram of a fourth embodiment, which is a specific circuit configuration of the third embodiment. Reference numerals in the figure indicate the same as those in FIG. The input current I ₁ , the primary winding current I _{2 of} the current feedback transformer 2, the collector currents I ₃ and I _{4 of the} transistors 1 and ₄ , the base drive currents I ₇ and I ₈ ,
Diode current I _5, the current waveform of I _6, and the switch 9
FIG. 8 shows the operation state of the twelfth embodiment. The operation is the same as that of the second embodiment, and the description is omitted. According to the fourth embodiment, the current feedback transformer, which conventionally requires two
In addition to this, the collector current of any transistor can be fed back. In this embodiment,
Transistors are NPN type, but in the case of using the PNP-type, the direction of the diode 7 and 8 in the opposite, winding N _5, N ₈ of windings N ₂ and the drive transformers 13 and 14 of current feedback transformer 2 The same effect can be obtained by reversing the polarity.

[0013]

As described above, according to the present invention,
In a drive circuit for connecting two transistors, each having an anti-parallel diode connected between the emitter and the collector, between emitter terminals or between collector terminals, and supplying a drive current for the two transistors by feedback of a collector current, A current feedback transformer is inserted between the emitter terminal or the collector terminal connecting the two transistors and the anode terminal or the cathode terminal connecting the two diodes, so that only one current feedback transformer is used. Thus, a small and simple driving circuit for a bidirectional connection transistor can be realized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a diagram showing a current waveform of each part of the first embodiment of the present invention.

FIG. 3 is a configuration diagram of a second embodiment of the present invention.

FIG. 4 is a diagram showing a current waveform of each unit and an operation state of a switch according to a second embodiment of the present invention.

FIG. 5 is a configuration diagram of a third embodiment of the present invention.

FIG. 6 is a diagram showing a current waveform of each part according to the third embodiment of the present invention.

FIG. 7 is a configuration diagram of a fourth embodiment of the present invention.

FIG. 8 is a diagram showing a current waveform of each part and an operation state of a switch according to a fourth embodiment of the present invention.

FIG. 9 is a configuration diagram showing a conventional example of a driving circuit for a bidirectional connection transistor.

[Explanation of symbols]

 1,4 ... transistor 2,5 ... current feedback transformer 3,6 ... base current supply circuit 7,8,15,16,17,18 ... diode 9,10,11,12 ... switch 13,14 ... drive transformer 19 ... Input terminal 20 ... Output terminal

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-63216 (JP, A) JP-A-61-224726 (JP, A) JP-A-55-1443837 (JP, A) 191383 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H03K 17/00-17/70 H02M 1/00-1/30

Claims (2)

(57) [Claims] The present invention relates to a bi-directional switch device in which two anti-parallel diodes are connected between emitter and collector and a bi-directional switch element connected in series between emitter terminals. Wherein a current feedback transformer is inserted between the emitter terminal connecting the two transistors and the anode terminal connecting the two diodes. Drive circuit. 2. A two-transistor element having an anti-parallel diode connected between an emitter and a collector and a bidirectional switch element connected in series between collector terminals. Wherein a current feedback transformer is inserted between the collector terminal connecting the two transistors and the cathode terminal connecting the two diodes. Drive circuit.