JP2017208988A - Switching power supply device and clamp type semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a switching power supply device and a clamp type semiconductor device with reduced noise that have a high reverse power peak resistance.SOLUTION: A switching power supply device 1 comprises: a switching element 5; and a clamp type semiconductor device 10 that clamps a voltage applied to the switching element. The clamp type semiconductor device 10 comprises: a plurality of avalanche-rectification-diode-type or Zener-diode-type first diode chips laminated and connected electrically in series to each other so that a forward current flows in the same direction; and one or more second diode chips 18 connected electrically in series to the first diode chips, and in which a forward current flows in a direction reverse to the forward current of the first diode chips.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a switching power supply device and a clamp type semiconductor device.

  Switching power supplies using surge absorbing components such as clamp-type semiconductor devices and DCR snubbers are widely used as clamps for surge voltage exceeding a predetermined value applied to the main switch when the power supply is started to reduce ringing noise. (See Patent Documents 1 and 2).

  In particular, the switching power supply using the clamp type semiconductor device not only simplifies the configuration of the switching power supply device but also the clamp type when operating in a light load region (in the standby operation mode of the switching power supply device) as compared with the DCR snubber. Since the semiconductor device does not perform the clamping operation, the efficiency of the light load region is less likely to be lost. Therefore, the switching power source using the clamp type semiconductor device is widely used for a flyback power source or the like.

JP-A-10-234180 JP 2006-5351 A

  However, since the clamp type semiconductor device is slightly inferior to the DCR snubber in terms of noise suppression, when giving priority to noise suppression in a wide frequency band such as several hundred kHz to several GHz, it is necessary to operate at the time of light load region operation. At the expense of efficiency, a switching power supply must be configured using a DCR snubber, and there is a problem that it is difficult to achieve both efficiency improvement and noise suppression during load region operation.

  In recent years, the need for improving the reverse power peak withstand capability of clamp type semiconductor devices has increased, and even when the reverse power peak withstand capability is less than required, the DCR snubber is sacrificed at the expense of the efficiency during light load region operation. There has been a problem that a switching power supply must be configured using the.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a switching power supply device and a clamp type semiconductor device that have low noise in a wide frequency band and high reverse power peak tolerance.

  The present invention proposes the following matters in order to solve the above problems.

A switching power supply device comprising: a switching element; and a clamp-type semiconductor device that clamps a voltage applied to the switching element.
The clamp type semiconductor device
A plurality of avalanche rectifier diode-type or zener diode-type first diode chips electrically connected in series so that forward current flows in the same direction;
One or a plurality of second diode chips that are electrically connected in series to the first diode chip and cause a forward current to flow in a direction opposite to the forward current of the first diode chip;
The switching power supply device characterized by being provided is proposed.

  The first diode chip has proposed a switching power supply device characterized in that a silicon semiconductor substrate is doped with impurities, and the impurity concentration of doping is 1 × 10 ^ 16 or more.

  A switching power supply device is proposed in which the silicon semiconductor substrate is an N-type semiconductor substrate.

  A switching power supply device is proposed in which the silicon semiconductor substrate is a P-type semiconductor substrate.

  The second diode chip proposes a switching power supply device characterized in that the second diode chip is stacked and connected to the first diode chip.

  A switching power supply device is proposed in which the first diode chip and the second diode chip are sealed in a common mold resin.

  A switching power supply device has been proposed in which the mold resin has a dielectric constant of 2 or more and 20 or less.

  A switching power supply device is proposed in which at least a part of the mold resin is covered with a metal shield material.

  The second diode chip has proposed a switching power supply device characterized by having a reverse recovery time of 1 μsec or more.

  A switching power supply device is proposed in which the second diode chip is a Schottky barrier diode chip.

  The second diode chip proposes a switching power supply device characterized by being formed of a gallium nitride semiconductor or a silicon carbide semiconductor.

A plurality of avalanche rectifier diode-type or zener diode-type first diode chips electrically connected in series so that forward current flows in the same direction;
One or a plurality of second diode chips that are electrically connected in series to the first diode chip and cause a forward current to flow in a direction opposite to the forward current of the first diode chip;
Proposed semiconductor devices.

  The first diode chip has proposed a semiconductor device characterized in that a silicon semiconductor substrate is doped with impurities, and the impurity concentration of doping is 1 × 10 16 or more.

  A semiconductor device has been proposed in which the silicon semiconductor substrate is an N-type semiconductor substrate.

  A semiconductor device has been proposed in which the silicon semiconductor substrate is a P-type semiconductor substrate.

  A semiconductor device is proposed in which the second diode chip is stacked and connected to the first diode chip.

  A semiconductor device is proposed in which the first diode chip and the second diode chip are sealed in a common mold resin.

  A semiconductor device is proposed in which the mold resin has a dielectric constant of 2 or more and 20 or less.

  A semiconductor device is proposed in which at least a part of the mold resin is covered with a metal shield material.

  The second diode chip has proposed a switching power supply device characterized by having a reverse recovery time of 1 μsec or more.

  A switching power supply device is proposed in which the first diode chip and / or the second diode chip is a Schottky barrier diode chip.

  The second diode chip proposes a semiconductor device characterized in that it is formed of a gallium nitride semiconductor or a silicon carbide semiconductor.

  It is possible to provide a switching power supply device and a clamp type semiconductor device that have low noise in a wide frequency band and high reverse power peak tolerance.

1 is a circuit diagram showing a configuration of a switching power supply device 1 according to an embodiment of the present invention. 1 is an electrical connection diagram inside a clamp type semiconductor device 10 according to an embodiment of the present invention. 1 is an internal cross-sectional structure diagram illustrating a configuration example of a first diode chip 11 of a clamped semiconductor device 10 according to a first embodiment of the present invention. FIG. 4 is a cross-sectional structure diagram of a first diode chip 11 shown in FIG. 3. It is an internal cross-section figure which shows the structural example of the 1st diode chip 12 of the clamp type semiconductor device 10 which concerns on 2nd Embodiment of this invention. FIG. 6 is a cross-sectional structure diagram of a first diode chip 12 shown in FIG. 5. It is a comparison figure of the noise characteristic of the clamp type semiconductor device 10 which concerns on embodiment of this invention, and the conventional clamp type semiconductor device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  It should be noted that the constituent elements in the present embodiment can be appropriately replaced with existing constituent elements and the like, and various variations in combination with other existing constituent elements are possible. Therefore, the description of the present embodiment does not limit the contents of the invention described in the claims.

  FIG. 1 is a circuit diagram showing a configuration of a switching power supply device 1 according to an embodiment of the present invention. FIG. 2 is an electrical connection diagram inside the clamp type semiconductor device 10 according to the embodiment of the present invention.

  The switching power supply device 1 according to the embodiment of the present invention is an example configured as a ringing choke converter. Since the ringing choke converter has a generally known configuration, the details thereof will be omitted, and the clamp type semiconductor device 10 will be mainly described below.

  The switching power supply device 1 includes a rectifier bridge diode, a capacitor 3, a switching element 5, a control circuit 6, a rectifier diode 7, a capacitor 8, a clamp type semiconductor device 10, a transformer 30, a rectifier diode 41, A capacitor 42 and an output voltage control unit 50 are provided.

  FIG. 3 is an internal cross-sectional structure diagram showing a configuration example of the first diode chip 11 of the clamp type semiconductor device 10 according to the first embodiment of the present invention. FIG. 4 is a cross-sectional structure diagram of the first diode chip 11 shown in FIG.

  In the first embodiment of the present invention, the silicon semiconductor substrate of the first diode chip of the clamp type semiconductor device 10 is configured by an N-type semiconductor substrate.

  As shown in FIG. 3, the clamp type semiconductor device 10 includes a plurality of avalanche rectifier diode type or zener diode type first diode chips 11 and 13 that are electrically connected in series so that forward current flows in the same direction. , 15.

  The clamp type semiconductor device 10 is electrically connected in series to the first diode chips 11, 13, and 15, and allows a forward current to flow in a direction opposite to the forward current of the first diode chips 11, 13, and 15. Alternatively, a plurality of second diode chips 18 are provided.

  The clamp type semiconductor device 10 shown in FIG. 3 includes, for example, one second diode chip.

  For example, as shown in FIG. 3, the second diode chip 18 is stacked and connected together with the first diode chips 11, 13, and 15.

  For example, the first diode chips 11, 13, and 15 dope impurities into the silicon semiconductor substrate, and the doping impurity concentration is 1 × 10 ^ 16 or more. When such an impurity concentration is set, noise can be significantly reduced in a wide frequency band.

  The impedance in the breakdown region of the first diode chips 11, 13, and 15 is controlled by the impurity concentration in manufacturing.

  As shown in FIG. 4, the first diode chip 11 has an anode electrode 11a (P +) and a cathode electrode 11c (N +) formed on both sides of the chip. In the first embodiment, the first diode chips 13 and 15 are formed in the same manner as the first diode chip 11.

  The first diode chip can significantly reduce noise in a wide frequency band by optimally setting the impedance of each chip (first diode chips 11, 13, and 15) constituting the first diode chip.

  The first diode chips 11, 13, 15 and the second diode chip 18 according to the first embodiment are preferably sealed with a common mold resin.

  In addition, by using the above-described stacked structure, the reverse power peak withstand capability of the clamp type semiconductor device 10 can be significantly increased.

  FIG. 5 is an internal cross-sectional structure diagram showing a configuration example of the first diode chip 11 of the clamp type semiconductor device 10 according to the second embodiment of the present invention. FIG. 6 is a cross-sectional structure diagram of the first diode chip 12 shown in FIG.

  In the first embodiment of the present invention, the silicon semiconductor substrate of the first diode chip 12 of the clamp type semiconductor device 10 is configured by a P-type semiconductor substrate.

  As shown in FIG. 5, in the second embodiment, the clamp-type semiconductor device 10 includes a plurality of avalanche rectifier diode type or zener diode type electrically connected in series so that forward current flows in the same direction. One diode chip 12, 14, 16 and a second diode chip 18 are provided.

  The clamp type semiconductor device 10 shown in FIG. 5 includes, for example, one second diode chip.

  For example, as shown in FIG. 5, the second diode chip 18 is stacked and connected to the first diode chip.

  For example, the first diode chips 12, 14, and 16 dope impurities into the silicon semiconductor substrate, and the doping impurity concentration is 1 × 10 ^ 16 or more. When such an impurity concentration is set, noise can be significantly reduced in a wide frequency band.

  The impedance in the breakdown region of the first diode chips 12, 14, and 16 is controlled by the impurity concentration in manufacturing.

  As shown in FIG. 6, the first diode chip 12 has an anode electrode 12a (N +) and a cathode electrode 12c (P +) formed on both sides of the chip. In the second embodiment, the first diode chips 14 and 16 are formed in the same manner as the first diode chip 12.

  The first diode chips 12, 14, 16 and the second diode chip 18 according to the second embodiment are preferably sealed with a common mold resin.

  FIG. 7 is a comparison diagram of noise characteristics when the clamp type semiconductor device 10 according to the embodiment of the present invention is operated and noise characteristics of the conventional clamp type semiconductor device.

  As shown in FIG. 7, the noise characteristics when the clamp type semiconductor device 10 according to the embodiment of the present invention is operated can be significantly reduced as compared with the noise characteristics of the conventional clamp type semiconductor device. Has been confirmed.

  Here, when the mold resin has a dielectric constant of 2 or more and 20 or less, noise can be reduced more remarkably.

  Furthermore, when the mold resin is at least partially covered with a metal shield material, noise can be reduced more remarkably.

  Further, the second diode chip 18 can remarkably reduce noise when it has a characteristic that the reverse recovery time is 1 μsec or more.

  If the second diode chip 18 is a Schottky barrier diode chip, noise can be reduced more remarkably.

  If the second diode chip 18 is formed of a gallium nitride semiconductor or a silicon carbide semiconductor, noise can be reduced more remarkably.

  The clamp type semiconductor device 10 and the switching power supply device 1 using the same can remarkably reduce the noise level in a wide frequency band.

  Moreover, the clamp type semiconductor device 10 according to the embodiment of the present invention has a structure as described above, so that the reverse power peak withstand capability can be remarkably increased as compared with the conventional clamp type semiconductor device.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to embodiment mentioned above, A various deformation | transformation and application are possible within the range which does not deviate from the summary of this invention, The above-mentioned The present invention is not limited to the embodiment, and can be appropriately changed within the scope of the invention.

1: Switching power supply device 2: Rectifier bridge diode 3: Capacitor 5: Switching element 6: Control circuit 7: Rectifier diode 8: Capacitor 10: Clamp type semiconductor device 11, 12, 13, 14, 15, 16: First diode chip 18: Second diode chip 30: Transformer 31: Primary winding 32: Control winding 33: Secondary winding
41: Rectifier diode 42: Capacitor 50: Output voltage controller

Claims (22)

A switching power supply device comprising: a switching element; and a clamp-type semiconductor device that clamps a voltage applied to the switching element,
The clamp type semiconductor device includes:
A plurality of avalanche rectifier diode-type or zener diode-type first diode chips electrically connected in series so that forward current flows in the same direction;
One or a plurality of second diode chips that are electrically connected in series to the first diode chip and cause a forward current to flow in a direction opposite to the forward current of the first diode chip;
A switching power supply device comprising:   2. The switching power supply device according to claim 1, wherein the first diode chip is doped with an impurity in a silicon semiconductor substrate, and an impurity concentration of the doping is 1 × 10 ^ 16 or more.   The switching power supply device according to claim 2, wherein the silicon semiconductor substrate is an N-type semiconductor substrate.   The switching power supply device according to claim 2, wherein the silicon semiconductor substrate is a P-type semiconductor substrate.   5. The switching power supply device according to claim 1, wherein the second diode chip is stacked and connected to the first diode chip. 6.   6. The switching power supply device according to claim 1, wherein the first diode chip and the second diode chip are sealed with a common mold resin. 7.   The switching power supply device according to claim 6, wherein the mold resin has a dielectric constant of 2 or more and 20 or less.   8. The switching power supply device according to claim 6, wherein at least a part of the mold resin is covered with a metal shield material. 9.   9. The switching power supply device according to claim 1, wherein the second diode chip has a characteristic of a reverse recovery time of 1 μsec or more.   9. The switching power supply device according to claim 1, wherein the first diode chip and / or the second diode chip is a Schottky barrier diode chip. 10.   9. The switching power supply device according to claim 1, wherein the second diode chip is formed of a gallium nitride semiconductor or a silicon carbide semiconductor. A plurality of avalanche rectifier diode-type or zener diode-type first diode chips electrically connected in series so that forward current flows in the same direction;
One or a plurality of second diode chips that are electrically connected in series to the first diode chip and cause a forward current to flow in a direction opposite to the forward current of the first diode chip;
The clamp type semiconductor device provided.   13. The clamp type semiconductor device according to claim 12, wherein the first diode chip is doped with an impurity in a silicon semiconductor substrate, and an impurity concentration of the doping is 1 × 10 ^ 16 or more.   14. The clamp type semiconductor device according to claim 13, wherein the silicon semiconductor substrate is an N type semiconductor substrate.   The clamp type semiconductor device according to claim 13, wherein the silicon semiconductor substrate is a P-type semiconductor substrate.   The clamp type semiconductor device according to claim 12, wherein the second diode chip is stacked and connected to the first diode chip.   17. The clamp type semiconductor device according to claim 12, wherein the first diode chip and the second diode chip are sealed with a common mold resin.   The clamp type semiconductor device according to claim 17, wherein the mold resin has a dielectric constant of 2 or more and 20 or less.   The clamp type semiconductor device according to claim 17, wherein at least a part of the mold resin is covered with a metal shield material.   20. The clamp type semiconductor device according to claim 12, wherein the second diode chip has a characteristic that a reverse recovery time is 1 μsec or more.   The clamp type semiconductor device according to any one of claims 12 to 19, wherein the first diode chip and / or the second diode chip is a Schottky barrier diode chip.   The clamp type semiconductor device according to claim 12, wherein the second diode chip is formed of a gallium nitride semiconductor or a silicon carbide semiconductor.

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