JP2003180077A - High-speed switching diode module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-speed switching diode module which can reduce power loss as a whole, and to improve the efficiency of a power supply apparatus using the module. <P>SOLUTION: This high-speed switching diode module has a rectifying bridge and a free wheel diode connected in parallel with the rectifying bridge, and a harmonic component is shunted via the free wheel diode, to reduce: power loss produced by the forward voltage drop of the harmonic component. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a high speed switching diode module.

[0002]

2. Description of the Related Art FIG. 3 shows a circuit configuration of a conventional high speed switching diode module. In this FIG.
The rectangular-wave high-frequency AC power applied to the AC input terminal 2 of the diode chip D1, which constitutes a rectifying bridge,
It is rectified by D2, D3, D4, converted into DC power, and taken out from the DC output terminals 3, 4. The AC input terminals 1 and 2 are high-frequency electric power, for example, the inverter 12
Connected to the output of. The diode chip D1,
High-speed switching diode chips are used for D2, D3, and D4, but in the following description, high-speed switching is omitted and the diode chips are referred to.

Diode chips D1, D2, D3, D4
High-frequency power is rectified by and converted to DC power,
It is taken out from the DC output terminals 3 and 4, and the load L is energized through the filter circuit including the choke coil 6 and the smoothing capacitor 7. A ripple current flows in this filter circuit as a circulating current as indicated by a broken line. Therefore, ripple voltage is reduced and smoothed DC power can be taken out from the DC output terminals 3 and 4. D1, above
The diode chips D2, D3 and D4 have a function as a rectifying function of blocking a reverse current to flow a forward current and a function of a free wheel diode for passing a ripple current flowing as a circulating current.

Diode chips D1, D2, D3, D4
In addition to the rectified current, the ripple circulating current is also flowing to the device, so the amount of heat generated was increased accordingly. In particular, the ripple circulating current caused power loss due to the forward voltage drop of each of the two series diodes. For example, when the forward voltage drop of each diode chip is 1V when the current of output 50A is flowing, the total voltage drop of two series is 2V, so that a power loss of 100W is generated and the ripple is added. There was a power loss due to the circulating current, and all of this was released as heat. The power loss generated as a freewheel diode when the ripple circulating current is 10 A is
2Vx because it occurs due to the voltage drop of 2V in the series diode
20W with 10A. Heat generated by 100W + 20W power loss is generated by four diode chips D1, D2, D
It is shared by 3, D4. For this reason, the diode chip has a cause of heat generation in addition to the basic function of rectifying action, and the temperature rise of the diode chip increases the temperature of the chip, resulting in a decrease in reliability. In addition, the power loss due to the ripple circulating current has been a cause of lowering the efficiency of the power supply device.

[0005]

In the semiconductor module of the rectifying circuit connected to the inverter as described above, the reliability of the semiconductor module is improved and the power loss due to the ripple circulating current is reduced, and the power supply using this module is used. It was required to improve the efficiency of the device.

[0006]

[Means for Solving the Problems] In order to solve the above problems, the following configuration is adopted. A high-speed switching diode chip is fixed to the upper surface of a copper circuit provided on a metal base via an insulating layer to form a rectifying bridge, and the entire surface except the AC input terminal and DC output terminal and the lower surface of the metal base is sealed. In a high-speed switching diode module formed by molding with a material, a free wheel diode was added and fixed to the upper surface of the copper circuit so as to be electrically connected between the DC output terminals in the same direction as the output of the rectifying bridge. The rectification bridge bears the rectification current, and the ripple current, that is, the harmonic current is mainly shunted to the freewheel diode.

According to the second aspect of the present invention, the high speed switching diode chip forming the rectifying bridge is formed by the double diode chip to reduce the size of the copper circuit.
Here, the double diode chip is a PN junction semiconductor P
A diode chip in which one of the layer and the N layer is common and the other is divided into two to form a half bridge connection structure. More specifically, the P layer is common and the N layer is 2
In the case of a dual diode chip having a structure in which two independent cathodes are connected and the anodes are connected in parallel, or a P layer is divided into two with the N layer being common and two independent anodes are provided, and the cathode is There is a double diode chip with a structure connected in parallel. That is, one double diode chip is fixed to the same copper circuit and connected in parallel to form a half bridge, and the other double diode chip is fixed to the same copper circuit and connected in parallel to form a half bridge. A rectifying bridge was formed by connecting each of the bridge-formed ones in series. A single diode chip was connected between the output terminals in the same direction as another diode (rectifying bridge) in order to give a function as a freewheel diode.

According to a third aspect of the present invention, a triple diode chip in which one of a P layer and an N layer of a PN junction semiconductor is common and the other is divided into three to form a half bridge connection structure and a diode connected in parallel to the half bridge connection structure. The rectifier bridge and the freewheeling diode were formed by combining and the double diode chip. That is, a double diode is fixed to one copper circuit connected to the output terminal, and a triple diode is fixed to the other copper circuit.
Each diode chip was connected between the output terminals in the same direction with respect to other diodes in order to give a function as a freewheel diode. A rectifying bridge was formed by the remaining two diode chips in the triple diode chip and the double diode chip.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described. FIG. 1 is a structural view for explaining an embodiment according to the present invention, in which (A) is a plan view and (B) and (C) are cross-sectional views of a chip used in (A). FIG. 2 is a circuit diagram illustrating an embodiment according to the present invention. In FIGS. 1 and 2, four high speed switching diode chips D1, D2, D3, D are provided on the upper surface of the copper circuit 10 provided on one surface of the metal base 8 via an insulating layer (not shown).
4 is fixed to form a rectifying bridge. A high speed switching diode module is formed by molding the entire surface except the AC input terminals 1 and 2, the DC output terminals 3 and 4 and the lower surface of the metal base 8 with a sealing material not shown. First diode chip D1 and second diode chip D2
Means that the N-type semiconductor layer N is fixed to the copper circuit 10, and the third diode chip D3 and the fourth diode chip D4 are P
The type semiconductor layer P is fixed to a copper circuit different from the above, and each forms a half bridge. A rectifying bridge is configured by connecting each half bridge in series in the same current direction. This rectifier bridge rectifies the AC output of the inverter 12 as an input and supplies DC to the load L from the DC output terminals 3 and 4.

Since the high frequency AC of the inverter 12 is applied to the AC input terminals 1 and 2, the diode chips D1, D2, D3 and D4 are converted into DC power by using high speed switching diode chips. , 4 are supplied from the DC output terminals and are supplied to the load L, the ripple current shown by the broken line flows as a circulating current in the filter circuit including the choke coil 6 and the smoothing capacitor 7. Therefore, ripple voltage is reduced and smoothed DC power can be taken out from the DC output terminals 3 and 4.

The rectifying bridge is composed of four high speed switching diode chips D1, D2, D3 and D4, but a fifth high speed switching diode D having a function as a freewheel diode is provided for this.
5 was added and fixed to the upper surface of the copper circuit 10 so as to be electrically connected between the DC output terminal 3 (negative electrode) and the DC output terminal 4 (positive electrode) in the same direction as the output direction of the rectifying bridge.
Since the ripple circulating current is mainly made to flow through the freewheel diode of D5, the power loss due to the ripple current is transferred from the rectifying bridge to the freewheel diode D5 and the forward voltage drop is also halved to about 1V.
The diode chips of 2, D3 and D4 have a rectifying function of blocking a reverse current and flowing a forward current.

Since this ripple current is mainly shunted to the freewheel diode of D5, a forward voltage of only the diode chip D5 causes a power loss due to the ripple current. A forward voltage drop of about 1V and a ripple current of the diode D5 occur. The product of 10A results in a loss of 10W, which is half that of the conventional 20W. Since the conventional 20 W is subtracted from the burden of the diodes D1 to D4, the temperature rise is reduced accordingly. Power loss as a whole is 10
We were able to reduce W.

1 and 2, the high speed switching diode chip constituting the rectifying bridge is formed by a double diode chip to reduce the size of the copper circuit. That is, the first high-speed switching diode chip D1 and the second high-speed switching diode chip D2 are the N-type semiconductor layer N as shown in FIG.
And a double diode chip connected in parallel, which is fixed to the same copper circuit 10 and connected in parallel to form a half bridge, and the other third high speed switching diode chips D3 and fourth high speed The switching diode chip D4 has a P-type semiconductor layer P as shown in FIG.
A rectifier bridge by connecting two diode chips that are connected with each other to another same copper circuit and connected in parallel to form a half bridge, in series through connecting metal pieces C, respectively. Was formed. The single diode chip D5 was connected between the output terminals 3 and 4 in the same direction with respect to other diodes (rectifying bridges) in order to provide the function as a freewheel diode. In addition, in FIG. 1 (A), the hunting portion S1,
S2, S3, S4 and S5 denote soldering parts of the diode chip and the connecting metal piece C, and other hunting parts S1.
Reference numerals 1, S21, S31, and S41 denote soldered portions of the connecting metal piece C and the copper circuit.

With regard to claim 3, in FIG. 2, the first high speed switching diode chip D1 and the second high speed switching diode chip D2 are a double diode chip in which an N type semiconductor layer N is connected. A triple diode chip of D3, D4 and D5 connected by layer P was combined to form a rectifying bridge and a freewheel diode. That is, one copper circuit connected to the output terminal has a double diode and the other copper circuit has three diodes.
A series diode is fixed, and one diode chip D5 of the three series diode chips is connected between the output terminals in the same direction as other diodes in order to provide a function as a freewheel diode. A rectifying bridge was formed by the remaining two diode chips D3 and D4 in the triple diode chip and the double diode chip.
This contributes to cost reduction by reducing the man-hours required to position and mount the diode chip on the copper circuit, saving the space between chips, and reducing the overall size of the module.

Although not shown, in the case where the entire unit including the inverter 12 is molded as one block, and a module in which a rectifier connected to all stages of the inverter and rectifying commercial power is housed in the same block is also included. Included in this example.

According to the present invention, the internal power loss of the entire high-speed switching diode module is reduced, the efficiency of the power supply device incorporating this is improved, and it is possible to contribute to energy saving. Further, it is possible to eliminate the decrease in reliability due to the rise in the temperature of the semiconductor chip, which is of great industrial value.

[Brief description of drawings]

FIG. 1 is a structural diagram illustrating an embodiment according to the present invention,
The figure (A) shows a plan view, and the figures (B) and (C) show sectional views of the chip used in the figure (A).

FIG. 2 is a circuit diagram illustrating an embodiment according to the present invention.

FIG. 3 is a circuit diagram of a conventional fast switching diode module.

[Explanation of symbols]

1, 2 AC input terminal 3 DC output terminal (negative electrode) 4 DC output terminal (positive electrode) 5 Fast switching diode module 6 Choke coil 7 Smoothing capacitor 8 Metal base 10 Copper circuit 12 Inverter C connection metal piece D1 First fast switching Diode chip D2 Second fast switching diode chip D3 Third fast switching diode chip D4 Fourth fast switching diode chip D5 Fifth fast switching diode chip (free wheel diode) N N type semiconductor layer P P type semiconductor layer L load

Claims (3)

[Claims] 1. A high-speed switching diode chip is fixed to the upper surface of a copper circuit provided on a metal base via an insulating layer to form a rectifying bridge, and an AC input terminal, a DC output terminal, and a lower surface of the metal base are connected. A high-speed switching diode module formed by molding the entire surface except for a sealing material, which supplies a rectangular-wave high-frequency AC power to an AC input terminal and converts it into a DC, with a freewheel diode added. A high-speed switching diode, characterized in that it is fixed to the upper surface of the copper circuit so that it is electrically connected between the DC output terminals in the same direction as the output of the rectification bridge, and the rectification ripple current is mainly shunted to the freewheel diode. module. 2. A high-speed switching diode chip forming a rectifying bridge is a P layer or N layer of a PN junction semiconductor.
2. The high speed switching diode module according to claim 1, wherein one of the layers is common and the other is divided into two to form a half bridge connection structure in a double diode chip. 3. A triple diode chip and a double diode chip in which one of a P layer and an N layer of a PN junction semiconductor is common and the other is divided into three to form a half bridge connection structure and a parallel connection diode. The high speed switching diode module according to claim 1, wherein a rectifying bridge and a free wheel diode are formed in combination.