JPS5961221A - Switching circuit - Google Patents

Abstract

PURPOSE:To improve the composition efficiency of the whole switching circuit using a semiconductor by supplying the charge of a capacitor in a turn off characteristics improving circuit to the input or output side. CONSTITUTION:Input power applied between input terminals I1, I2 charges the capacitor C2 and is applied to output terminals O1, O2 through a diode D1 and a reactance L by switching a transistor (TR) Qo. The charge accumulated in the capacitor C2 at the time turning off the TR Q0 is discharged through the primary winding of a transformer Tr and the generated secondary winding induced voltage is supplied to the input or output circuit side.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a switching circuit using semiconductor elements.

For example, when the switching frequency of a transistor in a switching regulator or the like is increased, the switching power loss in the transistor increases, and the sleep power efficiency decreases. Therefore, conventionally, a switching transistor is used as shown in FIG. . In parallel with, diode D. A capacitor C8 is connected in series with a series circuit of the resistor R and a switching characteristic modification circuit C is provided to form a transistor Q. We are trying to improve the turn-off characteristics of That is, transistor Q. transistor Q by turning off. 'yv
Do the electrician with a diode between the cutter and the emitter.
Buffer this light by passing the capacitor C6IC through the transistor Q. When the resistor R is turned on, discharge is caused through the resistor R.

However, in this circuit, the resistance R
As a result, the efficiency of using this distributed power suffers.

The present invention has been made in consideration of the above points, and supplies the photoelectric charge of a capacitor in a turn-off characteristic improvement circuit connected in parallel between the collector and emitter of a transistor to the input side 1 or the output side. This provides a switching circuit for use.

An embodiment of the present invention will be described below with reference to FIGS. 2 to 5.

Figure 2 shows the basic structure of the present invention, in which the resistor R in the circuit of Figure 1 is replaced by a reconnaissance circuit consisting of a transformer and a capacitor C1. The same reference numerals as in the figure mean the same key points.

In this circuit, when transistor 9 turns off, diode D turns off. As mentioned above, the capacitor Co is photoelectrically charged by the valve. Next, transistor Q
When the capacitor C8 is turned on, the photoelectric charge of the capacitor C8 flows into the capacitor C1 via the primary winding set of the transformer Tr, and an output is generated in the secondary winding of the transformer Tr. The secondary output of this transformer Tr is supplied to the input side of the transistor switching circuit and to the output l111.

3 to 5 show the specific circuit configuration.

First, the 31st bacteria is configured as a step-down type regulator, which steps down the input from input terminals I, I2 and sends it to output terminals 01 and 02.
The input power seen between I2 and photovoltaic capacitor C2 as well as transistor Q. Due to the switching of output terminal 0 through diode D and reactor L. ,0
2 is given. Output vehicle, compressed transistor Q. It is determined by the switching duty ratio of Diode D
3 is the transistor Q described in Section II. The direct pressure generated in the secondary winding of the transformer Tr when the transformer is turned off is connected to the diode D2.
, together with the reactor L, form an electric path that connects to a load (not shown).

Next, as shown in FIG. 4, the boost type regulator V-1 is configured, and when the transistor 9 is turned on, the energy accumulated in the reactor during its on period is transferred to the input terminals I, , 1.
2, kK/fVc is superimposed between 0.2 and output terminal 0.2 through diode D4. ．． 02 Tokitrans T
The fields and fields that occur in the secondary winding set are also superimposed, increasing the Takeda effect. The capacitor C2 has a smoothing 1/fi inserted I1.

Furthermore, the 51st! &lU As an inverting regulator [tη
This is the transistor Q. When turned off, energy is stored in the reactor during its on period and is transferred to diode D4. D2 (released in the right direction). Ifi' of output terminal 01.02 at this time, jE
The polarity is opposite to that of input terminals I,, I,. Then, the stress generated in the secondary winding of the transformer T is superimposed on the output voltage. The capacitor C2 is for smoothing as in FIG.

Although the embodiment 1 column above shows an embodiment using a transistor, the present invention can also be applied to a circuit using a thyristor.

As described above, the present invention stores 1 load in the capacitor when the switching transistor is turned off, and discharges it through the primary wire of the transformer when the switching transistor turns on, resulting in 2 winding induced free pressure in the full input circuit.
Alternatively, the output circuit 1111 can be supplied to the output circuit 1111 so that it is leaked, and in the conventional Jin-no-Kami circuit (-r, the power consumed by the resistor can be effectively utilized), and the transistor switching circuit The overall overall effectiveness can also be improved.

[Brief explanation of drawings]

Fig. 1 shows a conventional turn-off characteristic improvement circuit for transistor switching circuits, Fig. 2 shows Imoto's circuit arrangement of the present invention, and Figs. It is a diagram showing a circuit in which the circuit of the present invention is added to +11. Qo...Suitable transistor, D...Diode, C...Capacitor, L...Reactor, T...
··Trance.

Claims (1)

[Claims] A series circuit of a diode and a first capacitor is connected in parallel to a semiconductor switching element, and a series circuit of a primary winding of a transformer and a second capacitor is inserted in parallel with the diode, and the element is turned off. When the device is turned on, the photoelectric charge of the first capacitor is transferred to the second capacitor via the primary winding of the transformer. , a transistor switching circuit configured to supply electric power to the input side or output (fill) of a semiconductor switching element while waiting for the secondary winding of the transformer.