JPH0533511U - DC-DC converter - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] It is an object of the present invention to provide a compact and economical converter in a DC-DC converter in which switching noise between lines during switching is reduced. [Configuration] Between each winding of the output conversion transformer, winding and core
It is characterized in that the dielectric material (resin) is applied or impregnated on a part or the whole of the space or the transformer.

Description

[Detailed description of the device]

[0001]

[Explanation of the field to which the device belongs]

 The present invention relates to a DC-DC converter, and more particularly, to suppressing switching noise of a compact high frequency converter.

[0002]

[Prior art and its problems]

 FIG. 1 is a conventional circuit diagram of this type, in which an input side (primary side) IN and an output side (secondary side, tertiary side, etc.) OUT are insulated from a transformer 4. Then, the direct current power between the primary side lines 1a-1b is switched by the switching element 5 and supplied to the primary winding 4a of the transformer 4, and is output to the secondary winding 4b and the tertiary winding 4C. The power is rectified and smoothed through the diodes D1 and D2 and the capacitors C1 and C2 and converted into DC power between the output lines 2a-2b and 3a-3b. Switching noise occurs during this switching. This noise is due to common mode noise due to switching between the primary side and the secondary side and the tertiary side of the converter, that is, between lines 1a-2a, 1b-2b and 1a-3a, 1b-3b. Occur. As a method for suppressing this common mode noise, generally, external capacitors 6 and 7 having impedance sufficiently low with respect to the switching frequency between the primary side, the secondary side and the tertiary side are used. Connection is performed as shown in Fig. 1.

However, the above-described conventional circuit has a drawback that not only the circuit configuration becomes large in size but also the cost becomes high because an external capacitor is required.

[0004]

[The purpose of the device]

 An object of the present invention is to provide a compact and economical converter that suppresses common mode switching noise without providing an external capacitor.

[0005]

[Means of the Invention for Solving Problems]

 The present invention is configured to reduce noise by coating or impregnating a resin as a dielectric between each winding of a transformer, between a winding and a core, or a part or the whole of a transformer.

[0006]

【Example】

 2A and 2B are structural views of a transformer applied to the converter of the present invention. FIG. 2A is a plan view, FIG. 2B is a side view, FIG. 2C is a front view, and FIG. A wire (coil), 10 is a core (iron core), 11 is a bobbin, 12 is a gap material, 13 is a lead terminal, and 14 is a resin material (dielectric). FIGS. 3, 4 and 5 are structural views showing another embodiment of the present invention, and FIG. 2 shows an example in which a resin 14 as a dielectric is applied or impregnated between the windings. 3 shows an example of application between the winding 9 and the core 10, FIG. 4 shows an example of application to a part of the transformer, and FIG. 5 shows an example of application to the entire transformer. (3)

<Table 1> (unit: mV) By the way, Table 1 above shows that in the circuit of FIG. Under the conditions of 40 V and current of 12 mA), the comparison data with the common mode noise coating material when 0.03 g of epoxy resin as a dielectric material is applied to a part of the transformer is shown. (4) <Table 2> (unit: mV) Table 2 above shows the data when 0.07 g was applied under the same conditions. In addition, Table 3 shows the comparison data before the connection of the common mode noise in the conventional example in which the external capacitors 6 and 7 are provided for comparison. (5) <Table 3> (unit: mV) As is clear from the above tables, the effect of reducing the common mode noise (noise) by applying the resin is almost the same as the effect when the external capacitors 6 and 7 (100 μF) of the conventional example are connected. Indicates.

[0007]

[Effect of the device]

 As is clear from the above description, according to the present invention, common mode noise can be reduced without providing a capacitor or the like, so that circuit miniaturization can be achieved, and it is economical and economical in practical use. Is big.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a compact high frequency DC-DC converter.

FIG. 2 is a structural diagram of one embodiment of the present invention (6)

FIG. 3 is a structural diagram of another embodiment of the present invention.

FIG. 4 is a structural diagram of another embodiment of the present invention.

FIG. 5 is a structural diagram of another embodiment of the present invention.

[Explanation of symbols]

 IN Input side OUT Output side 4 Transformer 5 Switching element 6 External capacitor 7 External capacitor 9 Winding 10 Iron core (core) 11 Bobbin 12 Gap material 13 Lead terminal 14 Resin

Claims (2)

[Scope of utility model registration request] 1. A switching element is connected to the input winding of a transformer whose input winding side and output winding side are insulated,
In a DC-DC converter in which a rectifying diode is connected to the output winding side, a resin as a dielectric is applied or impregnated between the windings of the transformer, between the winding and the core, or part or the whole of the transformer. A DC-DC converter characterized in that 2. The DC-DC converter according to claim 1, further comprising a plurality of output windings.