Power device

Patent metadata

Field	Value
Publication number	US-9421925-B2
Application number	US-201414192403-A
Country	US
Kind code	B2
Filing date	Feb 27, 2014
Priority date	Feb 23, 2012
Publication date	Aug 23, 2016
Grant date	Aug 23, 2016

Abstract

A power device possesses a built-in fuse function and can continue to normally operate after a short circuit failure. The power device includes a plurality of output cells, a plurality of bonding wires provided corresponding to the output cells, and a control terminal driving circuit. Each of the output cells includes an output transistor. First side electrodes of the output transistors are commonly coupled to a first power source. Each of second side electrodes of the output transistors is coupled to an output terminal through the corresponding bonding wire. The control terminal driving circuit supplies a drive signal to the control terminals of the individual output transistors to control the output transistors. Each of the bonding wires is designed to be fused and cut if the output transistor included in the corresponding output cell fails and is shorted.

First claim

What is claimed is:

1. A power control unit for use in an automobile, comprising:
a power device adapted to drive a load of the automobile, the power device including a first lead frame having a semiconductor chip mounted thereon, the first lead frame including a power source terminal adapted to couple with a battery, the semiconductor chip including a plurality of transistors coupled with the first lead frame and a second lead frame, the second lead frame being coupled with the load, each of the plurality of transistors is separately coupled with the second lead frame via a corresponding bonding wire, each bonding wire having a first end directly connected to one of the plurality of transistors and a second end directly connected to the second lead frame,
a control circuit for controlling each of the plurality of transistors; and
a microcomputer for controlling the power device.

2. The power control unit according to claim 1 , wherein the microcomputer supplies an input signal to the power device to control the power device,
wherein the power device enables or disables a supply of power to the load from the battery based on the input signal.

3. The power control unit according to claim 2 ,
wherein the microcomputer supplies the input signal to the control circuit of the power device.

4. The power control unit according to claim 1 ,
wherein the load is an engine of the automobile.

5. The power control unit according to claim 1 ,
wherein in response to a transistor from among the plurality of transistor being short-circuited, the bonding wire corresponding to the short-circuited transistor is fused and cut.

6. The power control unit according to claim 1 ,
wherein each of the plurality of transistors is a MOSFET.

7. The power control unit according to claim 6 ,
wherein each of the plurality of transistors is an n-channel MOSFET,
wherein a drain electrode of said each of the plurality of transistors is coupled with the first lead frame and a source electrode of said each of the plurality of transistors is coupled with the second lead frame.

8. The power control unit according to claim 6 ,
wherein a gate electrode of said each of the plurality of transistors is provided in a trench formed over a semiconductor substrate.

9. The power control unit according to claim 1 , further comprising a wire cut/uncut detection circuit generating a wire cut/uncut detection signal that indicates whether any one of the bonding wires is cut or none of the bonding wires is cut.

10. The power control unit according to claim 1 , further comprising a control terminal separation circuit,
wherein when a transistor from among the transistors is short-circuited, the control terminal separation circuit reduces the influence of a control terminal voltage of the short-circuited transistor on a control terminal voltage of the other transistors.

11. The power control unit according to claim 1 , further comprising a control terminal separation circuit and a control terminal driving circuit configured to supply a drive signal to a control terminal of the respective transistors,
wherein the control terminal separation circuit includes a plurality of diodes and a plurality of resistive elements,
wherein the diodes and the resistive elements are provided corresponding to the transistors, and
wherein each of the diodes as well as each of the resistive elements are provided between an output terminal of the control terminal driving circuit and the control terminal of the corresponding transistor.

12. The power control unit according to claim 1 , further comprising:
a control terminal driving circuit configured to supply a drive signal to a control terminal of the respective transistors; and
control terminal discharge circuit configured to discharge charges of the control terminal of the transistors to switch the transistors to an OFF state.

13. A power control unit comprising:
a first transistor and a second transistor each being mounted to a first lead frame that is connected to a battery;
a first bonding wire that forms a sole and direct electrical connection between the first transistor and a second lead frame connected to a load;
a second bonding wire that forms a sole and direct electrical connection between the second transistor and the second lead frame;
a control circuit for controlling the first transistor and the second transistor; and
a microcomputer for controlling a power device that controls the first and second transistors.

14. The power control unit according to claim 13 , wherein in response to the first transistor malfunctioning, the electrical connection between the first transistor and the second lead frame is broken.

Assignees

• Renesas Electronics Corp

Inventors

• Souma Osamu

Classifications

• H02J7/62

  against overcurrent · CPC title

• H02J7/663 Primary

  using battery or load disconnect circuits (H02J9/002 takes precedence) · CPC title

• H10W72/5445

  being orthogonal to a side surface of the chip, e.g. parallel arrangements · CPC title

• H10W90/756

  between a chip and a stacked lead frame, conducting package substrate or heat sink · CPC title

• H10W72/5475

  multiple bond wires connected to common bond pads at both ends of the wires · CPC title