JPS5919472Y2 - Triangular wave current generation circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a triangular wave current generation circuit used for generating a magnetic bubble driving rotating magnetic field.

A rotating magnetic field is used to drive the magnetic bubble, and the rotating magnetic field includes a circular rotating magnetic field and a rectangular rotating magnetic field, but the latter is superior in terms of start-stop control and its extremely simple circuit. .

The rectangular rotating magnetic field has a second
It is obtained by supplying triangular wave currents as shown in the figure with a phase shift of 90', and such triangular wave currents can be generated by the circuit shown in FIG.

In FIG. 1, two transistors are used as a pair to provide the necessary current capacity.

In other words, a high frequency of several 100 KHz is used for bubble drive, but a transistor of about 1 A (which controls a current of about 500 mA) is appropriate for the transistor that controls such high frequency current; However, there are problems in terms of size and price.

The same applies to diodes.

However, the required coil drive current is often larger than this, so in that case, a plurality of transistors are connected in parallel.

In the case of parallel connections, the problem is equal distribution of current, and for this purpose the circuit of FIG. 1 uses stabilizing resistors r1 to r12.

Now, an overview of the configuration and operation of the circuit shown in FIG. 1 will be explained. In this figure, Ql and Q2, Q3 and Q4 are transistors connected in parallel, and their bases are connected to input capacitors T1. T
It is connected to the secondary winding of 2.

The primary windings of these transformers are resistors r13. r14, transistor Q5. Connected between power supply (1) 1 and ground via Q6.

D9. DIO is transformer T1. This is a diode that absorbs the reverse voltage generated at T2.

Transistor Q1. Q2 and Q3. Q4 is the resistance r1~
r4, diodes D1-D4, and resistors r5-r7 in series with power supply (1) V2. (-)V, connected between diode D
1. D2 and D3. The connection point of D4 becomes the output terminal OUT, and a bubble drive magnetic field generating coil or the like (indicated by L in this figure) is connected between this terminal and the ground.

These output terminals OUT and power supply (G) ■2. ←)■There is a diode D5 between. D6, resistance r9. rlO and diode D7. D8 and resistors r1□ and r1□ are connected.

Two of these diodes Ds, Ds, etc. are used in parallel due to current capacity, space, etc., and a stabilizing resistor r1. r2 is the transistor Q1. For base current equalization of Q2, r3. r4 is a diode D1. It is for equalizing the current passing through D2.

Similarly, r5. r6 is a diode D3. The resistance r7. of the current through D4. r8 is the transistor Q3. The base current of Q4 is resistor r9. rlO is the diode D5. D6
of current through and resistor r10. r12 is a diode D7. This is for equalizing the current passing through D8.

To explain the operation, when a pulse signal Sg1 is input to the transistor Q1 at time t1, it is transmitted to the transistor Ql via the transistor and the transformer T1.

Add to the base of Q2, turn it on and let the current 11 flow through the path of the Qtrfi r4 crow.

Although the main impedance of the circuit is inductance, this current 11 rises linearly as shown in FIG.

When signal Sg1 disappears at time t2, transistor Q5 is turned off, and transistor Q1. Q2 is turned off as the base current is cut off.

The current then tries to disappear, but at this time a large induced voltage is generated in the coil L, and this induced voltage causes C)V - [rll -D, Ding L rt! A current 12 flows through a path Ds, and this current falls in a straight line as shown in the figure as the induced voltage decreases.

Next, at time t3, when the signal Sg2 is input to the transistor Q6, it is transmitted through the transistor Q6 and the transformer T2 to the transistors Q3. It joins the base of Q4 and turns on these transistors.

This result L -D3- r5- Qs -rt
Lower C) V! -1 'D4 n@Ck-rs- A reverse current flows through the path, and this current i3 becomes a current that linearly increases in the negative direction as shown in FIG.

Then, at time t4, the signal Sg2 disappears and the transistor Q
6 is off, the transistor Q3. Q4 is also turned off, and at this time, the voltage induced in the coil L causes L-LD, -r, and ■v.

A current flows through the path D@-rl6, and this current i4 becomes a current that rises linearly in the positive direction as shown in the figure.

Thereafter, similar switching operations are repeated to generate a triangular wave alternating current.

However, this circuit requires a large number of stabilizing resistors as shown in the figure.

This increases proportionally as three or four transistors are connected in parallel.

The present invention improves this point and requires only a small number of stabilizing resistors.

Next, this will be explained in detail with reference to the embodiment shown in FIG.

The same parts in FIG. 3 as in FIG. 1 are given the same reference numerals.

As is clear from the comparison with FIG. 1, the parallel diodes D1 and D2. D3 and D4. D5 and D6. D7 and D8 current equalization (stabilization) resistors r3 and r4. r5 and R6, r9 and rl
o, rll and rl2 are removed and Dl and D2. D3
and D4. D5 and D6. The parallel connection of D7 and D8 is broken and common resistors R1 and R2 are inserted between them, and the series connection point of these resistors R1 and R2 becomes the output terminal OUT.

The operation is the same as in FIG. 1, in which the signal Sg1 is input and the transistors Q5 and Q1 . When Q2 turns on, VtLQl rl Dl-RITL also -r! A rising current 11 flows in a straight line on the path to -, and when these transistors are turned off, a current 12 flows on the path evL knee R, = -L to -, and the side signal Sg2 is input and the transistor Q6 and therefore transistor Q3. When Q4 turns on L T R+ Ds Qs -r7- () VL
When a current i3 flows in the path of Rl DA Q4 r@j and these transistors are turned off, L7R+ Ds τ■V.

To L-%-” Current i4 flows through the path.

In either case, since each branch path includes resistors R1 and R2, current equalization is performed by these resistors, and there is no possibility that an excessive amount of current will flow in either branch path.

In other words, these resistors R1 and R2 are two, and the resistors r3~
This replaces a total of eight circuits r6, r9 to r12, and it is possible to greatly simplify the circuit.

The reason why such a drastic simplification is possible is that, as is clear from the energization situation described above, in the circuit of Figure 1, out of the eight resistors mentioned above, only two are always operating and the others are in a resting state. If this device is operated all the time as in the present invention, only two devices are required.

According to the present invention as described in detail above, the stabilizing resistor of a plurality of parallel-connected transistor circuits can be largely omitted, and the circuit can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a conventional triangular wave current generating circuit, FIG. 2 is an explanatory diagram of its operation, and FIG. 3 is a circuit diagram showing an embodiment of the present invention. In the drawing, Q1 to Q4 are first to fourth transistors, D1 to Q4 are
D8 are first to eighth diodes, rl, T2. T7゜T
8 is the first to fourth resistors, R1 and R2 are stabilizing resistors, Q5
．． T1 and Q6. T2 is the transistor Q1. Q2 and Q3. This is a circuit that provides a signal to turn on Q4.

Claims (1)

[Claims for Utility Model Registration] A series circuit of a first transistor, a first resistor, a first diode, a third diode, a third transistor, and a third resistor between power supplies, and a second transistor. , second
a series circuit of a resistor, a fourth diode, a fourth transistor, and a fourth resistor, a series circuit of a fifth diode and a seventh diode of opposite polarity, and a series circuit of a sixth diode and an eighth diode. and a series circuit of the first and third diodes, and connect the series connection points of the first and third diodes to the fifth and seventh diodes.
The series connection point of the second and fourth diodes was connected to the series connection point of the sixth and eighth diodes, and the series connection point of the second and fourth diodes was connected to the series connection point of the sixth and eighth diodes. A circuit is then connected to the output terminal via another stabilizing resistor to provide a signal to the first and second transistors to turn on these transistors for two periods, and a circuit is connected to the third and fourth transistors. A triangular wave current generating circuit characterized in that it is connected to a circuit that provides another signal to turn on these transistors for a period of 2 periods which is separated from a period of 2 periods.