Title of Invention

POWER ELECTRONICS DEVICES WITH INTEGRATED CONTROL CIRCUITRY

Abstract A power switch apparatus includes a substrate; a semiconductor die mounted on the substrate and including power electronics circuitry for a high power, alternating current motor application; gate drive circuitry mounted on the substrate and electrically coupled to the power electronics circuitry on the semiconductor die; and control circuitry mounted on the substrate and electrically coupled to the gate drive circuitry.
Full Text POWER ELECTRONICS DEVICES WITH INTEGRATED CONTROL
CIRCUITRY
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of United States provisional
patent application serial number 60/952,778, filed July 30, 2007, which is
incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention generally relates to power electronics
devices, and more particularly relates to power electronics devices with
integrated control circuitry.
BACKGROUND OF THE INVENTION
[0003] In recent years, advances in technology, as well as ever-evolving
tastes in style, have led to substantial changes in the design of automobiles.
One of the changes involves the complexity of the electrical systems within
automobiles, particularly alternative fuel vehicles, such as hybrid, electric, and
fuel cell vehicles. Such alternative fuel vehicles typically use one or more
electric motors, perhaps in combination with another actuator, to drive the
wheels. Additionally, such automobiles may also include other motors, as
well as other high voltage components, to operate the other various systems
within the automobile, such as the air conditioner.

[0004] Due to the fact that alternative fuel automobiles typically include
only direct current (DC) power supplies, direct current-to-alternating current
(DC/AC) inverters (or power inverters) are provided to convert the DC power
to alternating current (AC) power, which is generally required by the motors.
Such vehicles, particularly fuel cell vehicles, also often use two separate
voltage sources, such as a battery and a fuel cell, to power the electric motors
that drive the wheels. Thus, power converters, such as direct current-to-direct
current (DC/DC) converters, are typically also provided to manage and
transfer the power from the two voltage sources.
[0005] As the power demands on the electrical systems in alternative fuel
vehicles continue to increase, there is an ever increasing need to maximize the
efficiency and reliability of such systems. Additionally, there is a constant
desire to reduce the cost and space required by the components within the
electrical systems in order to minimize the overall cost and weight of the
vehicles. One particular source of increased cost is the direct bonded copper
substrates conventionally required of many power inverters.
[0006] Therefore, it is desirable to provide a power electronics device,
particularly an inverter, with attributes of low cost, high current, and compact
design. Furthermore, other desirable features and characteristics of the present
invention will become apparent from the subsequent detailed description and
the appended claims, taken in conjunction with the accompanying drawings
and the foregoing technical field and background.
SUMMARY OF THE INVENTION
[0007] In accordance with an exemplary embodiment, a power switch
apparatus includes a substrate; a semiconductor die mounted on the substrate
and including power electronics circuitry for a high power, alternating current
motor application; gate drive circuitry mounted on the substrate and

electrically coupled to the power electronics circuitry on the semiconductor
die; and control circuitry mounted on the substrate and electrically coupled to
the gate drive circuitry.
[0008] In accordance with another exemplary embodiment, an automotive
drive system includes an electric motor; a direct current (DC) power supply
coupled to the electric motor; a power inverter assembly coupled to the
electric motor and the DC power supply to receive DC power from the DC
power supply and provide alternating current (AC) power to the electric
motor. The power inverter assembly includes a substrate; a semiconductor die
mounted on the substrate and including power electronics circuitry for
converting the DC power to AC power; gate drive circuitry mounted on the
substrate and electrically coupled to the power electronics circuitry on the
semiconductor die; and control circuitry mounted on the substrate and
electrically coupled to the gate drive circuitry.
[0009] In accordance with yet another exemplary embodiment, a power
switch apparatus includes a printed circuit board (PCB) substrate with a first
side and a second side; a plurality of semiconductor die mounted on the first
side of the substrate, the semiconductor die including insulated gate bipolar
transistors (IGBTs) for a high power, alternating current motor application;
gate drive circuitry mounted on the first side of the substrate and electrically
coupled to the IGBTs of the semiconductor die; control circuitry mounted on
the second side of the substrate and electrically coupled to the gate drive
circuitry with an interconnect formed in a via through the substrate; and an
EMI shield formed in the substrate to isolate the control circuitry from the
semiconductor die.
DESCRIPTION OF THE DRAWINGS

[0010] The present invention will hereinafter be described in conjunction
with the following drawing figures, wherein like numerals denote like
elements, and wherein:
[0011] FIG. 1 is a schematic view of an exemplary automobile according
to one embodiment of the present invention; and
[0012] FIG. 2 is an exemplary layout of a power switch apparatus of the
inverter assembly of the automobile of FIG. 1.
DESCRIPTION OF AN EXEMPLARY EMBODIMENT
[0013] The following detailed description is merely exemplary in nature
and is not intended to limit the invention or the application and uses of the
invention. Furthermore, there is no intention to be bound by any expressed or
implied theory presented in the preceding technical field, background, brief
summary or the following detailed description.
[0014] Broadly, exemplary embodiments described herein provide more
compact and less expensive power electronics devices. More particularly,
exemplary embodiments provide an inverter assembly with semiconductor die,
gate drive circuitry, and control circuitry mounted on a relatively low cost
substrate.
[0015] The following description refers to elements or features being
"connected" or "coupled" together. As used herein, "connected" may refer to
one element/feature being mechanically joined to (or directly communicating
with) another element/feature, and not necessarily directly. Likewise,
"coupled" may refer to one element/feature being directly or indirectly joined
to (or directly or indirectly communicating with) another element/feature, and
not necessarily mechanically. However, it should be understood that although
two elements may be described below, in one embodiment, as being

"connected," in alternative embodiments similar elements may be "coupled,"
and vice versa. Thus, although the schematic diagrams shown herein depict
example arrangements of elements, additional intervening elements, devices,
features, or components may be present in an actual embodiment.
[0016] Further, various components and features described herein may be
referred to using particular numerical descriptors, such as first, second, third,
etc., as well as positional and/or angular descriptors, such horizontal and
vertical. However, such descriptors may be used solely for descriptive
purposes relating to drawings and should not be construed as limiting, as the
various components may be rearranged in other embodiments. It should also
be understood that FIGS. 1 and 2 are merely illustrative and may not be drawn
to scale.
[0017] FIG. 1 illustrates an automobile (or "automotive drive system") 10,
according to one embodiment of the present invention. The automobile 10
includes a chassis 12, a body 14, a number of wheels 16, and an electronic
control system 18. The body 14 is arranged on the chassis 12 and
substantially encloses the other components of the automobile 10. The body
14 and the chassis 12 may jointly form a frame. The wheels 16 are each
rotationally coupled to the chassis 12 near a respective corner of the body 14.
[0018] The automobile 10 may be any one of a number of different types
of automobiles, such as, for example, a sedan, a wagon, a truck, or a sport
utility vehicle (SUV), and may be two-wheel drive (2WD) (i.e., rear-wheel
drive or front-wheel drive), four-wheel drive (4WD), or all-wheel drive
(AWD). The automobile 10 may also incorporate any one of, or combination
of, a number of different types of engines, such as, for example, a gasoline or
diesel fueled combustion engine, a "flex fuel vehicle" (FFV) engine (i.e.,
using a mixture of gasoline and alcohol), a gaseous compound (e.g., hydrogen
and/or natural gas) fueled engine, a combustion/electric motor hybrid engine,
and an electric motor.

[0019] In the exemplary embodiment illustrated in FIG. 1, the automobile
10 is a hybrid vehicle, and further includes an actuator assembly 20, a battery
(or direct current (DC) power supply) 22, a power electronics device 24, and a
radiator 26. In this exemplary embodiment, the power electronic device 24 is
an inverter assembly and will be referred to below as such. The actuator
assembly 20 includes a combustion engine 28 and an electric motor/generator
(or motor) 30. As will be appreciated by one skilled in the art, the electric
motor 30 includes a transmission therein, and although not illustrated also
includes a stator assembly (including conductive coils), a rotor assembly
(including a ferromagnetic core), and a cooling fluid (i.e., coolant). The stator
assembly and/or the rotor assembly within the electric motor 30 may include
multiple electromagnetic poles (e.g., sixteen poles), as is commonly
understood.
[0020] Still referring to FIG. 1, in one embodiment, the combustion engine
28 and the electric motor 30 are integrated such that both are mechanically
coupled to at least some of the wheels 16 through one or more drive shafts 32.
The radiator 26 is connected to the frame at an outer portion thereof and
although not illustrated in detail, includes multiple cooling channels therein
that contain a cooling fluid (i.e., coolant) such as water and/or ethylene glycol
(i.e., "antifreeze") and is coupled to the engine 28 and the inverter assembly
24.
[0021] During operation, the vehicle 10 is operated by providing power to
the wheels 16 with the combustion engine 28 and the electric motor 30 in an
alternating manner and/or with the combustion engine 28 and the electric
motor 30 simultaneously. In order to power the electric motor 30, DC power
is provided from the battery 22 to the inverter assembly 24, which converts the
DC power into AC power, before the power is sent to the electric motor 30.
As will be appreciated by one skilled in the art, the conversion of DC power to
AC power is substantially performed by operating (i.e., repeatedly switching)

transistor circuitry in power switches of the inverter assembly 24, as discussed
below in reference to FIG. 2.
[0022] Referring to FIG. 2, an exemplary layout of a power switch
apparatus 100 in the inverter assembly 24 is shown in greater detail.
Generally, one or more power switch apparatus 100 form an inverter assembly
24. The power switch apparatus 100 and larger inverter assembly 24 are each
considered a "power electronics" device. Generally, power electronics is
technology associated with the efficient conversion, control and conditioning
of electric power by static means from its available input form into the desired
electrical output form. Such conversion is performed with semiconductor
switching devices such as diodes, thyristors and transistors, and substantial
amounts of electrical energy are processed. In contrast, other electronic
systems are concerned with transmission and processing of signals and data
and do not process substantial amounts of energy.
[0023] The power switch apparatus 100 particularly includes
semiconductor die 105 mounted on a substrate 110 and enclosed in a housing
120. The semiconductor die 105 may be soldered to the substrate 110,
although other arrangements are also possible. The semiconductor die 105
may include a semiconductor substrate (e.g., silicon substrate) with an
integrated circuit formed thereon that includes one or more of the switches in
the form of individual semiconductor devices, such as insulated gate bipolar
transistors (IGBTs), as is commonly understood. In one embodiment,
semiconductor die 100 generally includes a three-phase circuit coupled to the
motor 30 and the battery 22 (FIG. 1).
[0024] In one embodiment, the substrate 110 is a relatively low cost
substrate, such as a PCB. The substrate can be, for example, an
epoxy/fiberglass material, although other material can be used. Standard PCB
techniques can be used to mount and interconnect the various components on
the substrate 110. Generally, the power switch apparatus 100 does not require

a direct, or double, bonded copper (DBC) substrate or other type of substrate
with high thermal conductivity. Although a single substrate 110 is shown with
two semiconductor die 105, additional or few semiconductor die can be
provided, as well as additional substrates that form, for example, a switch
module.
[0025] Gate drive circuitry 130 is formed on the substrate 110. Generally,
the gate drive circuitry 130 converts logic level control signals into the
appropriate voltage and current for efficient, reliable switching of the power
switch apparatus 100, particularly the circuitry that forms the IGBTs on the
semiconductor die 105. In conventional power switches, gate drive circuitry is
provided on a separate substrate.
[0026] The power switch apparatus 100 also includes a number of wire
bonds 140 that interconnect the semiconductor die 105 to various conductive
members (e.g., bus bars) formed in or on the substrate 110 such that the
semiconductor die 105 is electrically coupled to the gate drive circuitry 130,
and the gate drive circuitry 130 can be coupled to components outside of the
power switch apparatus 100.
[0027] Exemplary embodiments provide a power switch apparatus 100
with integrated gate drive circuitry 130 that requires fewer interconnects than
conventional assemblies. For example, a separate gate drive board is not
necessary.
[0028] In one exemplary embodiment, control circuitry 150 can
additionally be mounted on the substrate 110. The control circuitry 150 can
include or be coupled to various sensors and automotive control modules, or
electronic control units (ECUs), such as an inverter control module and a
vehicle controller, and at least one processor and/or a memory which includes
instructions stored thereon (or in another computer-readable medium) for
carrying out the processes of the inverter assembly 24. Generally, the control
circuitry 150 produces a Pulse Width Modulation (PWM) signal for

controlling the switching action of the circuitry on the semiconductor die 105,
which then converts the PWM signal to a modulated voltage waveform for
operating the motor 30 (FIG. 1).
[0029] In the exemplary depicted embodiment, the control circuitry 150 is
mounted on an opposite side of the substrate 110 relative to the semiconductor
die 105 and gate drive circuitry 130, although in other embodiments, the
control circuitry 150 can be mounted on the same side of the substrate 110 as
the semiconductor die 105 and gate drive circuitry 130. Mounting the control
circuitry 150 on an opposite side relative to the semiconductor die 105 and
gate drive circuitry 130 provides isolation, particularly with an EMI shield 160
formed within the substrate 110. This isolation enables the relatively high
voltage circuitry on the semiconductor die 105 and the relatively low voltage
components of the control circuitry 150 to operate without interference. The
EMI shield 160 can be, for example, a layer of grounded, conductive material
within the substrate 110. In conventional power switches, gate drive circuitry
is provided on a separate substrate.
[0030] The control circuitry 150 can be coupled to the gate drive circuitry
130 through the substrate 110 with, for example, interconnects 170 in vias
175. The vias 175 can be formed, for example, by laser drilling or punching,
and in one embodiment, filled by thick film techniques. Thick film is a
technique of filling the vias 175 with a slurry or paste of one or more of un-
fired ceramic materials and metal powders, usually gold, and then firing the
slurry or paste to create the interconnects 170.
[0031] Exemplary embodiments provide a power switch apparatus 100 of
an inverter assembly 24 with integrated control circuitry 150 that requires
fewer interconnects than conventional assemblies. For example, a separate
control board is not necessary. This enables additional flexibility and
creativity in the electrical design.

[0032] As noted above, the power switch apparatus 100 also includes the
housing 120 that encloses the semiconductor die 105, substrate 110, and
associated circuitry. The housing 34 may be made of a molded plastic
material or any other suitable material.
[0033] During operation, the semiconductor die 105 generates heat. In
one embodiment, the semiconductor die 105 generates a heat flux density of at
least 10 W/cm2, while in another embodiment, generates a heat flux density of
at least 20 W/cm2. In order to remove heat from the semiconductor die 105,
the fluid within the radiator 26 is circulated by the pump 32 (FIG. 1) to one or
more nozzles 180 within the power switch apparatus 100. The fluid is sprayed
through the nozzles 180 onto the semiconductor die 105. Heat from the
semiconductor die 105 conducts to the fluid before the fluid runs off. The
fluid may then be collected and returned to the radiator 26, by the pump 32, to
be cooled within the cooling channels of the radiator 26 (FIG. 1). The coolant
fluid is preferably a dielectric liquid. As will be apparent to one skilled in the
art, the particular dielectric liquid selected will depend upon device chemistry
and application. Suitable dielectric liquids may include, but are not limited to,
fluorocarbons, silicone oils, and polyalphaolephins. In this exemplary
embodiment, the power switch apparatus 100 and/or inverter assembly 24
does not include a heat sink. Other examples of heat removal include
atomizers and other cooling mechanisms.
[0034] While at least one exemplary embodiment has been presented in
the foregoing detailed description, it should be appreciated that a vast number
of variations exist. It should also be appreciated that the exemplary
embodiment or exemplary embodiments are only examples, and are not
intended to limit the scope, applicability, or configuration of the invention in
any way. Rather, the foregoing detailed description will provide those skilled
in the art with a convenient road map for implementing the exemplary
embodiment or exemplary embodiments. It should be understood that various
changes can be made in the function and arrangement of elements without

departing from the scope of the invention as set forth in the appended claims
and the legal equivalents thereof.

CLAIMS
What is claimed is:
1. A power switch apparatus, comprising:
a substrate;
a semiconductor die mounted on the substrate and comprising
power electronics circuitry for a high power, alternating current motor
application;
gate drive circuitry mounted on the substrate and electrically
coupled to the power electronics circuitry on the semiconductor die; and
control circuitry mounted on the substrate and electrically coupled
to the gate drive circuitry.
2. The power switch apparatus of claim 1, wherein the
substrate is a printed circuit board (PCB).
3. The power switch apparatus of claim 1, wherein the power
electronics circuitry includes insulated gate bipolar transistors (IGBTs).
4. The power switch apparatus of claim 1, wherein the
semiconductor die is mounted on the substrate with solder.
5. The power switch apparatus of claim 1, wherein the gate
drive circuitry is configured to receive logic level control signals from the
control circuitry and to convert the control signals into appropriate voltage and
current for controlling switching of the power electronics circuitry.
6. The power switch apparatus of claim 1, further comprising
wire bonds for electrically coupling the gate drive circuitry to the power
electronics circuitry on the semiconductor die.

7. The power switch apparatus of claim 5, wherein the
semiconductor die is a first semiconductor die and the inverter assembly
further comprises a second semiconductor die mounted on the substrate.
8. The power switch apparatus of claim 1, further comprising a
housing for enclosing the substrate and the semiconductor die.
9. The power switch apparatus of claim 8, further comprising
nozzles coupled to the housing for delivering a cooling fluid to the
semiconductor die.
10. The power switch apparatus of claim 1, wherein the
substrate has a first side and a second side, the semiconductor die being
mounted on the first side and the control circuitry being mounted on the
second side.
11. The power switch apparatus of claim 10, wherein the gate
drive circuitry is mounted on the first side.
12. The power switch apparatus of claim 11, further comprising
an EMI shield formed in the substrate to isolate the control circuitry from the
semiconductor die.
13. The power switch apparatus of claim 11, wherein the gate
drive circuitry is electrically coupled to the control circuitry with an
interconnect formed in a via through the substrate.
14. An automotive drive system comprising:
an electric motor;
a direct current (DC) power supply coupled to the electric motor;
a power switch apparatus coupled to the electric motor and the DC
power supply to receive DC power from the DC power supply and provide

alternating current (AC) power to the electric motor, the power switch
apparatus comprising:
a substrate;
a semiconductor die mounted on the substrate and
comprising power electronics circuitry for converting the DC power to AC
power;
gate drive circuitry mounted on the substrate and electrically
coupled to the power electronics circuitry on the semiconductor die; and
control circuitry mounted on the substrate and electrically
coupled to the gate drive circuitry.
15. The automotive drive system of claim 14, wherein the
substrate is a printed circuit board (PCB).
16. The automotive drive system of claim 14, wherein the power
electronics circuitry includes insulated gate bipolar transistors (IGBTs).
17. The automotive drive system of claim 14, wherein the
substrate has a first side and a second side, the semiconductor die being
mounted on the first side and the control circuitry being mounted on the
second side.
18. The automotive drive system of claim 17, wherein the gate
drive circuitry is mounted on the first side.
19. The automotive drive system of claim 18, further comprising
an EMI shield formed in the substrate to isolate the control circuitry from the
semiconductor die.

20. A power switch apparatus, comprising:
a printed circuit board (PCB) substrate with a first side and a
second side;
a plurality of semiconductor die mounted on the first side of the
substrate, the semiconductor die including insulated gate bipolar transistors
(IGBTs) for a high power, alternating current motor application;
gate drive circuitry mounted on the first side of the substrate and
electrically coupled to the IGBTs of the semiconductor die;
control circuitry mounted on the second side of the substrate and
electrically coupled to the gate drive circuitry with an interconnect formed in a
via through the substrate; and
an EMI shield formed in the substrate to isolate the control
circuitry from the semiconductor die.

A power switch apparatus includes a substrate; a semiconductor die
mounted on the substrate and including power electronics circuitry for a high
power, alternating current motor application; gate drive circuitry mounted on
the substrate and electrically coupled to the power electronics circuitry on the
semiconductor die; and control circuitry mounted on the substrate and
electrically coupled to the gate drive circuitry.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=K7/L0wRYwJ6s693kcKBPlQ==&loc=wDBSZCsAt7zoiVrqcFJsRw==


Patent Number 268510
Indian Patent Application Number 1302/KOL/2008
PG Journal Number 36/2015
Publication Date 04-Sep-2015
Grant Date 31-Aug-2015
Date of Filing 30-Jul-2008
Name of Patentee GM GLOBAL TECHNOLOGY OPERATIONS, INC.
Applicant Address 300 GM RENAISSANCE CENTER, DETROIT, MICHIGAN
Inventors:
# Inventor's Name Inventor's Address
1 GREGORY S. SMITH 24907 VISTA VERANDA WOODLAND HILLS, CALIFORNIA 91367
2 DAVID TANG 13795 BENNINGTON COURT FONTANA, CALIFORNIA 92336
3 JAMES M. NAGASHIMA 16608 MOORBROOK AVENUE CERRITOS, CALIFORNIA 90703
4 GABRIEL GALLEGOS-LOPEZ 3700 REDONDO BEACH BOULEVARD, APT. B TORRANCE, CALIFORNIA 90504
5 DAVID F. NELSON 29100 MEDEA LANE AGOURA HILLS, CALIFORNIA 91301
6 GEORGE JOHN 18847 ALEXANDER AVENUE CERRITOS, CALIFORNIA 90703
PCT International Classification Number H02J7/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/982778 2007-07-30 U.S.A.
2 12/178478 2008-07-23 U.S.A.