JP2693016B2 - Hybrid integrated circuit device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a hybrid integrated circuit device in which a power active filter is mounted on an insulating metal substrate, and more specifically, from an insulating metal substrate based on switching operation to an external structure. The present invention relates to a hybrid integrated circuit device mounted with an active filter in which leakage current to the circuit is suppressed.

(B) Conventional technology In recent years, active filters have attracted attention in terms of measures against rectified power supply noise. A general active filter will be described with reference to FIG.

Active filter bridge rectifier circuit composed of diodes D ₁ to D _4, a reactor L that is connected between the commercial AC power source represented by the AC input terminal and the voltage V _ac of the bridge rectifier circuit, the DC output of the pair of the bridge rectifier circuit The circuit is composed of a transistor Q connected in parallel between the terminals, a capacitor C _d for smoothing the DC output of the bridge rectifier circuit, and a damper diode D ₅ connected between the DC output terminal of the bridge rectifier circuit and the smoothing capacitor C _d. . Note that a control circuit for outputting a control pulse φ having a frequency of 15 KHz or higher for controlling the operation of the transistor Q is omitted.

 Next, the operation of the active filter will be described.

In the half cycle in which the reactor L side of the commercial AC is positive, while the transistor Q is turned on by the high-level control pulse φ, a closed circuit is formed by the reactor L-diode D ₁ -transistor Q-diode D ₄ to form the reactor L During the half cycle in which the reactor L side of the commercial AC is negative, a closed circuit is formed by the diode D ₂ -transistor Q-diode D ₃ -reactor L while the transistor Q is on, and the reactor L Current flows through
When the control pulse φ goes low and the transistor Q is turned off, the previous two closed circuits are opened, and a counter electromotive force is generated in the reactor L. Since this back electromotive force has the same phase as the commercial alternating current, a voltage obtained by adding the back electromotive force of the reactor L and the voltage of the commercial alternating current is input to the bridge rectifier circuit while the transistor Q is turned off. smoothing capacitor a damper diode D ₅ and a forward bias
_Charged to C _d .

Conventionally, this active filter is configured by discrete components. However, the wiring between the discrete components becomes longer, and new switching noise is induced by the inductance component of the wiring. For this reason, it is necessary to house the active filter in a large shield structure, and it has not been possible to sufficiently meet the demand for a reduction in the size of the power supply device.

Therefore, the inventor of the present invention has proposed a hybrid integrated circuit device in which the active filter is mounted on an insulating metal substrate in Japanese Patent Application No.
No. 2580 proposed. Next, the hybrid integrated circuit device will be described with reference to FIG.

That is, both surfaces of a metal substrate (40) made of aluminum or the like are covered with an insulating oxide film (42) formed by anodizing, and an insulating resin layer (4) made of epoxy or the like is formed on one of the insulating oxide films (42).
A circuit pattern (48) of copper foil is formed via 6).
The diodes D _{1 to} D ₄ are placed on this circuit pattern (48).
A very small active filter is realized by surface-mounting D and D ₅ , transistor Q, and circuit components constituting a control circuit in a chip shape. As is clear from FIG. 7, the ground pattern of the circuit pattern (48) is used to remove the stray capacitance due to the insulating oxide film (42) and the insulating resin layer (46). ) It is connected to the lower metal substrate by a bonding wire (54).

When such a hybrid integrated circuit device is incorporated in an electronic device, it is usual that the insulating oxide film (42) on the back surface of the metal substrate (40) is brought into contact with the chassis and mounted with a structure with good heat dissipation. Accordingly, in this structure, a stray capacitance _Cp (see FIG. 8) having at least the insulating oxide film (42) as a dielectric is formed between the metal substrate (40) and the chassis of the electronic device over the entire surface of the metal substrate (40).

(C) Problems to be Solved by the Invention However, in the above-described hybrid integrated circuit device, the emitter potential of the transistor Q of the active filter fluctuates greatly at high frequencies, which causes noise on the chassis of the electronic device via the insulating metal substrate. There is a peculiar problem due to the use of the insulating metal substrate that it flows out.

The cause of this problem will be described with reference to FIGS.

FIG. 8 (A) shows an equivalent circuit of the hybrid integrated circuit device in a half cycle in which the reactor L side of the commercial AC is positive. In the positive half cycle, a closed circuit is formed by the reactor L-diode D ₁ -transistor Q-diode D ₄ , and the reactor L is located at a position where the collector load of the transistor Q is obtained.

On the other hand, FIG. 8B shows an equivalent circuit of the hybrid integrated circuit device in a half cycle in which the commercial AC reactor L side is negative. In the negative half cycle, the diode D ₂ - transistor Q- diode D ₃ - closed circuit is formed by the reactor L, the reactor L is emitter load of transistor Q.

As is apparent from this, in the positive half cycle (FIG. 8 (A)), the collector potential of the transistor Q causes the control pulse φ between the charging voltage of the smoothing capacitor C _d and the ground potential.
It changes so that it may switch at the frequency of. Note that the emitter potential is maintained at the ground potential. However, in the negative half cycle (FIG. 8 (B)), the reactor L acts as the emitter load of the transistor Q, so that the emitter potential switches between the charging voltage of the smoothing capacitor C _d and the ground potential at the frequency of the control pulse φ. To change.

Since the ground pattern of the hybrid integrated circuit device and the aluminum substrate (40) are connected by the bonding wire (54), the potential of the aluminum substrate (40) charges the smoothing capacitor C _{d in} the negative half cycle. It changes so as to switch between the voltage and the ground potential at the frequency of the control pulse φ. This flows as a switching noise in the chassis of the electronic device via the stray capacitance C _p formed between the chassis of an electronic device an aluminum substrate (40). The hybrid integrated circuit device described in the conventional example has a structure in which a circuit pattern is formed via an insulating resin layer on a metal substrate, but the above-mentioned problem is not limited to this structure, and for example, on an insulating resin layer on a metal substrate. This also occurs in a hybrid integrated circuit device having a structure in which a metal layer is provided on the entire surface of and a circuit pattern is formed through an insulating resin.

(D) Means for Solving the Problems The present invention has been made in view of the above problems, and an active filter having a circuit configuration for connecting a reactor between an output end of a rectifier circuit and a switching element is mounted on an insulating metal substrate. By doing so, it is possible to realize a hybrid integrated circuit device in which the conventional problems are greatly improved.

(E) Operation Since the active filter with the circuit configuration in which the reactor is connected to the DC output terminal of the rectifier circuit and the other end of the reactor is intermittently grounded by the switching element is made into a hybrid integrated circuit device, it can be used in any phase of commercial AC. Also, the reactor acts as a collector load for the transistor,
The application of the high frequency switching voltage to the pattern is eliminated. Therefore, for example, when connected to the ground pattern,
Since the high frequency switching voltage is not applied to the metal substrate, it is possible to prevent the switching noise from flowing out through the stray capacitance caused by the mounting structure of the hybrid integrated circuit device.

(F) Embodiment FIG. 1 shows a circuit configuration of a characteristic active filter employed in the present invention.

As shown in the figure, the active filter includes a bridge rectifier circuit including diodes D _{1 to} D ₄ , a reactor L having one end connected to a positive DC output terminal of the bridge rectifier circuit, which is a feature of the present invention, A transistor Q ₀ having a collector and an emitter connected between the other end of the reactor L and the ground, a damper diode D ₅ having an anode connected to the collector of the transistor Q ₀ , a cathode of the damper diode D ₅ and the ground. It is composed of a smoothing capacitor C _d and a control circuit COM that supplies a control pulse φ to the base of the transistor Q ₀ connected between them.

The main circuit of the control circuit COM is constituted by a microcomputer and outputs a control pulse φ having a frequency of 15 KHz or more. Although not shown, the control circuit CO
M is the frequency of the control pulses φ detects the magnitude of the load current, or perform feedback control by the duty, more active filters can not run away thermally by measuring the emitter current of the substrate temperature and the transistor Q ₀ Such control is also performed. Note that the control circuit CO of the present embodiment is
Although a microcomputer is used for M, it is needless to say that the predetermined control can be performed by a known circuit configuration such as a comparator and an operational amplifier.

The transistor Q ₀ is not limited to the bipolar transistor shown in the figure, and can be changed to other elements capable of high-speed operation such as a power MOS transistor, SIT, and IGBT. In addition, the rectifier circuit is not limited to the illustrated bridge rectifier circuit, and any well-known rectifier circuit can be used.

Next, referring to FIG.
The operation of the filter will be described.

In the half cycle in which the potential at the connection point between the commercial AC diodes D ₁ and D ₃ is positive, when the control pulse φ output from the control circuit COM and having a frequency of 15 KHz or higher is at high level, the transistor Q ₀
Turns on, diode D ₁ -reactor L -transistor Q ₀
- the closed circuit of the diode D ₄ is formed a current to the reactor L
i _L flows. Then, when the control pulse φ is at the low level, the transistor Q ₀ is turned off and the previous closed circuit is opened,
Reactor L generates a back electromotive force in an attempt to connect the previous electrical state. The voltage obtained by adding the counter electromotive force of the reactor L and the output of the bridge rectifier circuit exceeds the charging voltage of the smoothing capacitor C _d for a longer period as compared with the capacitor input type rectifier circuit, and passes through the damper diode D _5. Charge the smoothing capacitor C _d .

In the half cycle in which the potential of the connection point between the commercial AC diodes D ₁ and D ₃ is negative, the transistor Q ₀ turns on when the control pulse φ is at high level, and the diode D ₂ -reactor L-transistor Q ₀ -diode A closed circuit of D ₃ is formed and a current i _L flows through the reactor L. Then, when the control pulse φ becomes the low level and the transistor Q ₀ is turned off and the previous closed circuit is opened, the counter electromotive force is generated in the reactor L as in the previous case, and the counter electromotive force and the output of the bridge rectifier circuit are generated. The smoothing capacitor C _d is charged by the voltage to which is added.

Further details will be described with reference to FIGS. 3 (A) and 3 (B).

FIG. 3A shows an equivalent circuit of the hybrid integrated circuit device in the half cycle in which the potential at the connection point of the commercial AC diodes D ₁ and D ₃ is positive. In this positive half cycle, the diode
A closed circuit is formed by D ₁ -reactor L-transistor Q ₀ -diode D ₄ , and the reactor L is located at a position to be a collector load of the transistor Q ₀ .

On the other hand, FIG. 3 (B) shows a diode for commercial alternating current.
The equivalent circuit of the hybrid integrated circuit device in a half cycle in which the connection point potential of D ₁ and D ₃ is negative is shown. In the negative half cycle,
Diode D ₂ - reactor L- transistor Q ₀ - by the diode D ₃ a closed circuit is formed, the reactor L is similar to the positive half cycle a collector load of transistor Q _0.

Therefore, according to the circuit configuration of the active filter, in the positive half cycle of the commercial AC, is always the reactor L is inserted into the collector of the transistor Q ₀ in the negative half cycle, the emitter potential of the transistor Q ₀ is Always stable to ground potential.

Referring to FIG. 4, the active filter described above is
Except for the reactor L and a smoothing capacitor C _d, illustrating a specific structure of the embodiment mounted on the insulated metal substrate.

The hatched circuit pattern is a ground pattern, and the circuit board is formed by a part of the ground pattern, and the small signal circuit block corresponding to a blank portion in substantially the upper half of the drawing and the large circuit corresponding to the lower half of the drawing. It is divided into two current circuit blocks. In this embodiment, the wiring of the control pulse φ supplied from the small signal circuit block to the large current circuit block or the wiring of the emitter potential of the transistor Q ₀ supplied from the large current circuit block to the small signal circuit block is the ground pattern. However, the present invention is not limited to this, and for example, the wiring of the emitter potential of the transistor Q ₀ is connected to a predetermined position of the small signal block by a bonding wire (jumping wire connection). ) May be.

Furthermore, this ground pattern is connected to the aluminum substrate by a bonding wire W at a position closest to the emitter of the transistor Q ₀ through which a high frequency and a large current flows, so that the aluminum substrate potential becomes equal to the ground pattern potential.

The large-current circuit block, the diode D ₁ to D ₄ constituting the bridge rectifier circuit, a damper diode D _5, the transistor Q ₀ is surface-mounted through a heat sink, further limiting the emitter current of the transistor Q _0, also An emitter resistance R for measuring the value is formed. These elements are respectively arranged so that a large current does not flow in the ground pattern section dividing the small signal circuit block and the large current circuit block. The external lead terminals connecting the large current circuit block and the external circuit and the external lead terminals of the small signal block are arranged on the opposite peripheral edges of the circuit board so that mutual coupling is reduced.

Further, since the distance between the externally connected smoothing capacitor C _d and the damper diode D ₅ has a great influence on the charging / discharging ability of the smoothing capacitor C _d , the damper diode D ₅ is close to the terminal indicated by V ⁺ in FIG. Are placed. Further, for the same reason, the terminal indicated by V ⁺ and the ground terminal GND are arranged adjacent to each other.

The cross-sectional structure of the hybrid integrated circuit device shown in FIG. 4 is common to that of FIG.

The above-described hybrid integrated circuit device of the present invention is attached to the chassis of the electronic device with the back surface of the insulating metal substrate in contact with the chassis of the electronic device in consideration of heat dissipation. The stray capacitance C _p are between the metal substrate and the chassis of the insulated metal substrate to have a structure interposed as shown in Figure 3. However, since the metal substrate is connected to the ground pattern (hatched portion in FIG. 4) by the bonding wire W, the potential of the metal substrate becomes the same as the potential of the ground pattern.
According to the present invention, a ground pattern, that is, the emitter potential of the transistor Q ₀ is stable at the ground potential as described above, the negative switching noise in a half cycle of the commercial AC through the stray capacitance C _p is There is no danger of spillage into the chassis.

 FIG. 5 shows a circuit diagram of a modified example of the embodiment.

The control circuit COM of the above embodiment has a function of outputting multiphase pulses for controlling the inverter circuit, and outputs the multiphase pulses from the hybrid integrated circuit device to the outside. Such a hybrid integrated circuit device has the advantage that it can be constructed on a relatively small scale, but has the disadvantage that it requires a large number of terminals for externally outputting polyphase pulses.

On the other hand, in the modification, the three-phase inverter circuit including the transistors Q _{1 to} Q ₆ is also mounted on a single circuit board, and the control circuit COM transfers the transistor Q to the transistor Q via the circuit pattern formed on the circuit board. polyphase pulse is input to the base of ₁ to Q _6. Thus, the number of terminals is reduced and noise is prevented from being mixed into wiring between the active filter and the inverter circuit.

(G) Effects of the Invention As described above, according to the hybrid integrated circuit device of the present invention, (1) since the potential of the emitter of the transistor of the active filter is at the ground potential at high frequency, the metal substrate of the hybrid integrated circuit device. It is possible to provide an extremely high performance hybrid integrated circuit device that improves the performance of a set of electronic devices without the risk of outflow of switching noise from the device to the chassis of the electronic devices.

(3) Since the inter-element wiring constituting the active filter is shortened by adopting the hybrid integrated circuit device, noise due to wiring inductance is suppressed.

(4) Since the insulating metal substrate is used as the circuit substrate, a relatively large stray capacitance is formed between the wiring pattern and the metal substrate, and the harmonic noise can be quickly attenuated in the vicinity of the place where the harmonic noise is generated.

(5) Since the insulated metal substrate is used as the circuit board, the heat radiation characteristics are good, and the active filter can be made compact.

(6) Since the insulated metal substrate is used as the circuit board, unnecessary radiation from the hybrid integrated circuit device to the outside can be suppressed. Further, in the hybrid integrated circuit device of the present invention, when the active filter and the inverter circuit are mounted on the same substrate, the noise mixed in the wiring connecting the active filter and the inverter circuit can be significantly suppressed. it can.

[Brief description of the drawings]

FIG. 1 is a circuit diagram illustrating an active filter used in the present invention, FIG. 2 is an operation waveform diagram of the active filter, and FIGS. 3 (A) and 3 (B) are diagrams illustrating changes in the emitter potential of the transistor of the present invention. FIG. 4 is an equivalent circuit diagram of each half cycle of commercial AC, FIG. 4 is a plan view of an embodiment, FIG. 5 is a circuit diagram of a modified example, and FIG. 6 is an active circuit of a conventional example.
FIG. 7 is a circuit diagram of the filter, FIG. 7 is a cross-sectional view of the circuit board, and FIGS. 8A and 8B are diagrams for explaining changes in the emitter potential of the transistor of the conventional example, which are equivalent to each half cycle of commercial AC. It is a circuit diagram. L ...... reactor, D ₁ ~D ₅ ...... diodes, C _d ...... smoothing capacitor, Q ₀ ...... transistor, COM ...... control circuit.

Continuation of front page (56) Reference JP 62-106657 (JP, A) JP 3-7066 (JP, A) JP 4-320506 (JP, A) JP 1-152960 (JP , A) JP-A-4-33362 (JP, A) JP-A-4-33363 (JP, A) Electronic Technology, Vol. 32, 1990 No. 3, pages 85-89

Claims (1)

(57) [Claims] 1. A rectifier circuit that constitutes an active filter, a switching element, and a diode that extracts a charging voltage from the switching element are mounted on a circuit pattern of an insulating metal substrate, and a DC output terminal of the rectifier circuit and the switching circuit are provided. A hybrid integrated circuit device characterized in that a reactor is connected between the elements, and a charging capacitor is connected to the output side of the diode.