FIELD OF THE INVENTION
The present invention relates to a system for operating one or more loads.
BACKGROUND
Generally, switches are being widely used in automobiles from a long time for switching on and
off various applications in a vehicle. These applications include stop lamp, cruise control,
electronic stability function, engine start stop function, etc.
From above mentioned applications, the stop lamp is discussed for the sake of an example. A stop
lamp switch is generally operated by pressing of vehicle brakes. The stop lamp switch starts
operating, the moment the brakes of a vehicle are applied. The lights or the stop lamps remain in
ON condition as long as the brake lever is pressed. This function is provided for safety reasons.
The reason behind providing this function is to alert a driver, who is driving behind or following
the vehicle. As soon as the brakes are applied the driver of the oncoming vehicle will be alerted
and he can take necessary action in order to avoid collisions with vehicle in front.
However, the drivers run a risk of collision when they have to stop their vehicle on a road side for
some duration of time. Pressing the brakes for a long duration of time is very tiresome for the
driver to keep stop lamp ON. Thus, it becomes very difficult for a driver of an approaching vehicle
to spot a vehicle in front which has stopped on road side while it is dark.
Therefore, it is the need of the art to provide a system that drives one or more loads of a vehicle
such as a stop lamp when the vehicle is stationary, which can be spotted by a driver of an oncoming
vehicle and he can take precautionary action.
OBJECT OF THE INVENTION
An object of the present invention is to provide a system which can turn ON one or more loads of
the vehicle.
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Another object of the present invention is to provide a system that eliminates the need of pressing
brakes to turn on the one or more loads.
SUMMARY OF THE INVENTION
One or more shortcomings of the prior art are overcome and additional advantages are provided
by the present disclosure. Additional features and advantages are realized through the techniques
of the present disclosure. Other embodiments and aspects of the disclosure are described in detail
herein and are considered a part of the disclosure.
It is to be understood that the aspects and embodiments of the disclosure described above may be
used in any combination with each other. Several of the aspects and embodiments may be
combined together to form a further embodiment of the disclosure.
In an aspect, the present disclosure provides a system for driving one or more loads of a vehicle.
The system comprises a driving circuit comprising a first transistor electrically connected to said
one or more loads, an ignition switch defining a plurality of stages including ACCESSORY stage
to be selected by a user of the vehicle, and an electronic control unit (ECU) electrically connected
to the ignition switch and the driving circuit, said ECU comprising a first resistor; a second resistor,
a second transistor electrically connected to the first resistor, a third transistor electrically
connected to the second resistor, and a controller electrically connected to the second and third
transistors for selectively operating said second and third transistors for turning ON the first
transistor, in response to selection of the ACCESSORY stage.
In another aspect, the present disclosure provides a system, wherein the driving circuit comprises
a diode having positive and negative terminals, and a pair of resistors arranged between the diode,
first transistor and a battery of the vehicle, and wherein the negative terminal of the diode being
electrically connected to the second and third transistors.
In yet another aspect of the disclosure, a system is provided, wherein the controller has at least an
input port for receiving an input signal from the ignition switch in response to selection of one of
the plurality of stages and at least first and second output ports, the first output port being
electrically connected to the second transistor and the second output port being electrically
4
connected to the third transistor; and wherein the controller turns ON the third transistor in
response to selection of the ACCESSORY stage.
In yet another aspect of the disclosure, a system is provided, wherein the plurality of stages defined
by the ignition switch further includes LOCK/VEHICLE OFF stage and VEHICLE ON stage; and
wherein the controller turns ON the second transistor in response to the selection of
LOCK/VEHICLE OFF stage and VEHICLE ON stage.
In yet another aspect of the disclosure, a system is provided, wherein the first transistor is
electrically connected to said one or more loads via a high side driver.
In yet another aspect of the disclosure, a system is provided wherein the first, second and third
transistors are selected from a group comprising Bipolar Junction Transistor or Field Effect
Transistor or Metal Oxide Semiconductor Field Effect Transistor.
In yet another aspect of the disclosure, a system is provided, wherein the first resistor has a high
resistance value to block flow of current.
In yet another aspect of the disclosure, a system is provided, wherein resistance values of first and
second resistors are selected based on a) battery voltage and/or b) resistance values of the pair of
resistors.
In yet another aspect of the disclosure, a system is provided, wherein said one or more loads are
selected from rear combination stop lamp and/or high mounted stop lamp.
BREIF DESCRIPTION OF DRAWINGS
Further aspects and advantages of the present invention will be readily understood from the
following detailed description with reference to the accompanying drawings. Reference numerals
have been used to refer to identical or similar functionally similar elements. The figures together
with a detailed description below, are incorporated in and form part of the specification, and serve
to further illustrate the embodiments and explain various principles and advantages, in accordance
with the present invention wherein:
5
Figure 1 represents a block diagram of a system for driving one or more loads of a vehicle.
Figure 2 illustrates a circuit diagram showing components of a system of Figure 1.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, there is shown an illustrative embodiment of the invention a system
for driving one or more loads of a vehicle. It should be understood that the invention is susceptible
to various modifications and alternative forms; specific embodiment thereof has been shown by
way of example in the drawings and will be described in detail below. It will be appreciated as the
description proceeds that the invention may be realized in different embodiments.
Before describing in detail embodiments it may be observed that the novelty and inventive step
that are in accordance with the present invention reside in the construction of the system for driving
one or more loads of a vehicle accordingly, the drawings are showing only those specific details
that are pertinent to understanding the embodiments of the present invention so as not to obscure
the disclosure with details that will be readily apparent to those of ordinary skill in the art having
benefit of the description herein.
The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a nonexclusive
inclusion, such that a setup, device that comprises a list of components does not include
only those components but may include other components not expressly listed or inherent to such
setup or device. In other words, one or more elements in a system or apparatus proceeded by
“comprises… a” does not, without more constraints, preclude the existence of other elements or
additional elements in the system or apparatus.
The present disclosure relates to a system to drive one or more loads of a vehicle without the need
of continuously pressing the brakes to turn on such loads.
Figure 1 represents a block diagram of a system for driving one or more loads of a vehicle in
accordance with an embodiment of the present invention. The system comprises an Electronic
Control Unit (ECU) electrically coupled to an ignition switch, a driving circuit, and a high side
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driver coupled to one or more loads of a vehicle. The one or more loads of a vehicle are selected
from rear combination stop lamp and/or high mounted stop lamp.
In an embodiment of the present invention, the ignition switch may be a key operated switch. In
this embodiment of the present invention, the ignition switch includes a lock where a mechanical
key is inserted to START the vehicle. The ignition switch according to this embodiment defines a
plurality of stages including LOCK/VEHICLE OFF stage, ACCESSSORY stage and VEHICLE
ON stage. At the LOCK/VEHICLE OFF stage, the vehicle is in OFF state, that is, engine and other
functions/electrical systems of the vehicle, for example, accessories are not operational. At the
ACCESSORY stage, the engine of the vehicle is OFF, however, battery supplies power to few
electrical systems such as radio, power window etc. At the VEHICLE ON stage, the engine of the
vehicle is ON and other electrical systems are also ON.
In another embodiment of the present invention, the ignition switch may be a keyless switch. In
this embodiment of the present invention, the ignition switch is implemented as a push button
START/STOP switch. In this embodiment, the push button switch is activated by an electronic
key (FOB key). The electronic key should be in a pre-determined range of the push button switch
to activate the switch. The ignition switch according to this embodiment also defines a plurality of
stages including LOCK/VEHICLE OFF stage, ACCESSSORY stage and VEHICLE ON stage.
At the LOCK/VEHICLE OFF stage, the vehicle is in OFF state, that is, engine and other
functions/electrical systems of the vehicle, for example, accessories are not operational. At the
ACCESSORY stage, the engine of the vehicle is OFF, however, battery supplies power to few
electrical systems such as radio, power window etc. At the VEHICLE ON stage, the engine of the
vehicle is ON and other electrical systems are also ON.
When a user of a vehicle selects the ACCESSORY stage of the ignition switch, the ECU
electrically connected to the ignition switch receives a high signal from the said ignition switch.
The ECU in response to said high signal activates the driving circuit. Upon activation, the driving
circuit turns ON one or more loads electrically connected to it via the high side driver. The high
side driver is provided to have integrated fault protection under extreme conditions. Thus, the one
or more loads are turned ON even if no brakes are applied.
7
Figure 2 illustrates a circuit diagram showing components of the system in accordance with an
embodiment of the present invention. As discussed in above paragraphs, the system comprises an
electronic control unit (201) electrically coupled to a driving circuit (202) which is implemented
as a transistor logic function, said driving circuit (202) is electrically coupled to a high side driver
(203).
The ECU (201) comprises a controller (1) having at least one input port (A) and at least first (B)
and second (C) output ports, a second transistor (2) having first, second and third terminals, said
first terminal of the second transistor being electrically connected to a battery and said second
terminal of the second transistor being electrically connected to the first output port (B) of the
controller, a first resistor (5) having first (a) and second (a’) ends, said first end (a) of the first
resistor (5) being electrically connected to the third terminal of the second transistor (2) and said
second end (a’) of the first resistor (5) being electrically connected to ground; a third transistor (3)
having first, second and third terminals, said first terminal of the third transistor (3) being
electrically connected to the battery and said second terminal of the third transistor (3) being
electrically connected to the second output port (C) of the controller (1); and a second resistor (4)
having first (b) and second (b’) ends, said first end of the second resistor (4) being electrically
connected to the third terminal of the third transistor and said second end (b’) of the second resistor
(4) being electrically connected to ground;
The driving circuit (202) comprises a first transistor, a diode (6) and a third (8) and fourth (9)
resistors. The first transistor (10) having first, second and third terminals. The diode having
positive and negative terminals, said negative terminal of the diode being electrically connected to
the first terminal of both the second (2) and third (3) transistors, and its positive end is electrically
connected to the second terminal of the first transistor (10). The third resistor (8) having first (c)
and second (c’) ends, said first end (c) of the third resistor (8) being electrically connected to the
positive terminal of the diode and said second end (c’) of the third resistor being electrically
connected to the second terminal of the first transistor (10). The fourth resistor (9) having first (d)
and second (d’) ends, said first end (d) of the fourth resistor (9) being electrically connected to the
battery and said second end (d’) of the fourth resistor being electrically connected to the second
end (c’) of third resistor (8) as well as to the second terminal of the first transistor (10).
8
The high side driver (203) having one of its input electrically connected to the third terminal of
the first transistor (10) and one of its output being electrically connected to said one or more loads.
The high side driver (203) is a monolithic silicon chip which combines control and protection
circuitry with a standard power MOSFET structure where the power stage current flows vertically
through the silicon. High Side Drivers, with their integrated extra features are power switches that
can handle high currents and work up to about 40V supply voltage. Said high side drivers require
only a simple TTL logic input and incorporate a fault condition status output. For complete
protection the devices have an over temperature sensing circuit that will shut down the chip under
over-temperature conditions.
In operation, when the user of a vehicle selects the ACCESSORY stage, the controller receives a
high signal at its input port (A). In response to receiving said signal, the controller triggers the third
transistor (3) that receives a battery voltage at its first terminal. Since, the resistance value of the
second resistor (4) is nominal, preferably 150 ohms, but not limited thereto, the battery voltage is
grounded through said second resistor (4). Thus, the first terminal of the third transistor (3)
provides a zero voltage at the second terminal of the first transistor to turn it on. When the first
transistor (10) is turned on, an output voltage at the third terminal of the first transistor (10) turns
ON one or more loads via the high side driver (203).
On the other hand, if the user of the vehicle selects any one of LOCK/VEHICLE OFF stage, or
VEHICLE ON stage, the controller receives a low signal at its input port (A). In response to
receiving said signal, the controller triggers the second transistor (2) that receives a battery voltage
at its first terminal. Since, the resistance value of the first resistor (5) is very high as compared to
the first resistor (4), preferably 15K ohms, but not limited thereto, said first resistor blocks flow of
current to ground. Thus, the first terminal of the second transistor (3) provides a high voltage at
the second terminal of the first transistor to keep it OFF. Since, the first transistor is not triggered
on, the on one or more loads connected to it via the high side driver (203) will remain OFF.
The above operations can be understood clearly from the below mentioned table:
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Signal received by
controller
Second
Transistor (2)
Third
Transistor (3)
First
Transistor
(10)
One or more
loads
LOCK/VEHICLE
OFF, or VEHICLE
ON
ON OFF OFF OFF
ACCESSORY OFF ON ON ON
The first, second and third transistors as represented in the figures are PNP transistors. However,
it is to be noted that this should not be treated as a limiting example. These transistors are selected
from a group comprising Bipolar Junction Transistor or Field Effect Transistor or Metal Oxide
Semiconductor Field Effect Transistor. Also, the same may not be construed as limiting examples.
Further, as shown in Fig. 2, third resistor (8) R4 and fourth resistor (9) R5 provide biasing to the
first transistor (10). A capacitor (7) acts as spike absorbent and the diode (6) provide any reverse
battery protection to the first transistor (10). The condition to judge that the first transistor is
whether ON or OFF is considered in between voltage range of 8~16V DC defined in table below:
VOLTAGE
(V) DC R4 R5
ECU LOAD
CUREER2 R1 NT
16
560E 5.6K
15K 743.2uA
combination -
1
8 15K 369.1uA
16 150E 2.582mA
8 150E 1.22mA
16
560E 1K
15K 947.7uA
combination
-2
8 15K 469.9uA
16 150E 12.63mA
8 150E 5.814mA
Increase in current consumption of circuit when value of resistance 5.6k change to 1k ohm
Thus, it may be noted from the above discussion that, the value of resistance of first resistance is
kept significantly larger than the resistance value of second transistor. Also, the value of first (5)
and second (4) resistors depends on the value of third (8) and fourth (9) resistors. It is seen from
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the above table that if the specific combination (combination-1) of resistance values (R1, R2, R4
and R5) of the resistors that is preferably used in the present invention is changed to another
combination of resistance values, there is increase in current consumption. Thus, the preferable
specific combination-1 used in the present invention results in significantly lesser current
consumption.
The controller may include an application programming interface for building software
applications, a memory to store data related to its processing, a processing unit and a
communication unit connected to a bus. A processing unit may further comprise a processor and
a plurality of processing subsystems. The controller may be any programmable microprocessor,
microcomputer or multiple processor chip or chips or an ASIC that can be configured to perform
a variety of functions, including the functions of the various embodiments described above.
A controller may have an internal memory or an external memory to store related data. Typically,
data may be stored in the memory before they are accessed and loaded into the Controller. For the
purposes of this description, the term memory refers to all memory accessible by the server,
including external memory and memory within the server itself. The memory may be volatile or
nonvolatile memory, such as flash memory, or a mixture of both.
While the invention has been described with reference to a preferred embodiment, it is apparent
that variations and modifications will occur without departing the theme of the invention. It is
therefore contemplated that the present invention covers any and all modifications, variations or
equivalents that fall within the scope of the basic underlying principles disclosed above and
claimed therein.
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We Claim:
1. A system for driving one or more loads of a vehicle, comprising:
a driving circuit comprising a first transistor electrically connected to said one or
more loads;
an ignition switch defining a plurality of stages including ACCESSORY stage to
be selected by a user of the vehicle; and
an electronic control unit (ECU) electrically connected to the ignition switch and
the driving circuit, said ECU comprising:
a first resistor;
a second resistor;
a second transistor electrically connected to the first resistor;
a third transistor electrically connected to the second resistor; and
a controller electrically connected to the second and third transistors for
selectively operating said second and third transistors for turning ON the first transistor, in
response to selection of the ACCESSORY stage.
2. The system as claimed in claim 1, wherein:
the driving circuit comprises:
a diode having positive and negative terminals; and
a pair of resistors arranged between the diode, first transistor and a battery of the
vehicle; and
wherein the negative terminal of the diode being electrically connected to the
second and third transistors.
3. The system as claimed in claim 1, wherein the controller has at least an input port for
receiving an input signal from the ignition switch in response to selection of one of the
plurality of stages, and at least first and second output ports, the first output port being
electrically connected to the second transistor and the second output port being electrically
connected to the third transistor; and
wherein the controller turns ON the third transistor in response to selection of the
ACCESSORY stage.
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4. The system of claims 1 and 3, wherein the plurality of stages defined by the ignition switch
further includes LOCK/VEHICLE OFF stage and VEHICLE ON stage; and
wherein the controller turns ON the second transistor in response to the selection
of the LOCK/VEHICLE OFF stage or VEHICLE ON stage.
5. The system of claim 1, wherein the first transistor is electrically connected to said one or
more loads via a high side driver.
6. The system as claimed in claim 1, wherein the first, second and third transistors are selected
from a group comprising: Bipolar Junction Transistor or Field Effect Transistor or Metal
Oxide Semiconductor Field Effect Transistor.
7. The system of claim 1, wherein the first resistor has a high resistance value to block flow
of current.
8. The system as claimed in claims 1 and 2, wherein resistance values of first and second
resistors are selected based on a) battery voltage; and/or b) resistance values of the pair of
resistors.
9. The system as claimed in claim 1, wherein said one or more loads are selected from rear
combination stop lamp and/or high mounted stop lamp.