FIELD OF THE INVENTION:
The present invention relates to dimmer circuits and in particular relates to operation in the
dimmer circuits.
BACKGROUND OF THE INVENTION:
Dimmer circuits are known to control illumination of lightening device(s). Specifically,
in case of AC power based illumination devices, dimmer circuits chop/cut off of a portion of
total energy of the AC signal reaching an illumination device. The dimmer circuits usually
includes a zero detection circuit for detecting zeros in an AC wave, around which the AC
power signal is eventually chopped off, a logic device for timing a particular dimmer level
around the detected zeros, and a dimmer unit for altering the AC power signal in accordance
with the signal generated by the logic device, thereby generating a final control signal for
performing the dimming action to an electrical load.
Specifically, the logic device or microcontroller accepts the zero crossing and dimmer
value as separate inputs, and processes them to construct a specific periodic signal that
includes a particular dimmer level timed around the detected zeros. The dimmer unit mixes
such periodic signal with an input alternating current power signal, thereby altering the AC
power signal, and feeds the same to a target load so as to produce a desired level dimming
action.
Whenever multiples illumination devices having different dimmer values (or dimmer
levels) connected to a common AC source are targeted to be dimmed, an equal number of
logic devices (micro-controllers) and dimmer units are required to be connected in parallel to
a zero cross detector so as to produce the corresponding dimmer circuits. Accordingly, in
case of multiple illumination devices having separate dimmer levels, a substantial
expenditure is always incurred due to a presence of a plurality of logic devices and other
subordinating components. Moreover, presence of a large number of logic devices
complicates the circuitry and requires a substantial time to manufacture.
Thus, there is a need to provide at least a centralized control mechanism for multiple
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dimmer circuits.
SUMMARY OF THE INVENTION:
This summary is provided to introduce a selection of concepts in a simplified format that are
further described in the detailed description of the invention. This summary is not intended to
identify key or essential inventive concepts of the claimed subject matter, nor is it intended
for determining the scope of the claimed subject matter.
Accordingly, in accordance with the purposes of the invention, the present invention as
embodied and broadly described herein provides a device for controlling an operation in a
dimmer circuit. The device comprises a procurement module forprocuring at least two values
corresponding to at least two dimmer levels and receiving a reference point detected
detection within a first type of signal. A pulse-generator is configured to trigger periodically a
pulse within a second type of signal for each of said at least two dimmer levels based upon
the occurrence of reference point within the first type of signal. The width of pulse within
each second type of signal is based on the value of the respective dimmer level. Further, an
output module communicates said second type of signals comprising the periodical pulses
respectively to at least two dimmer units to cause generation of at least two dimmer signals.
In another embodiment of the present invention, a method has been provided controlling an
operation in a dimmer circuit. The method includes procuring at least two values
corresponding to at least two dimmer levels and receiving a reference point detected within a
first type of signal; triggering periodically, from a single source, a pulse within each a second
type of signal for each of said at least two dimmer levels based upon the occurrence of
reference point within the first type of signal, such that the width of pulse within each second
type of signal is based on the value of the respective dimmer levels; and communicating said
second type of signals comprising the periodical pulses to respective at least two dimmer
units to cause generation of at least two dimmer signals.
At least by virtue of aforesaid, the present subject matter described herein is able to dim an
AC signal to numerous different dimming values for an array of electrical devices through a
single logic device. In other words, the present subject matter at least ensures that the
complexity of a dimmer circuit is substantially reduced due to provision of a centralized
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controlling system for dimming multiple electrical devices. The same not only leads to a
lesser incurrence of expenditure, but also economizes the power-consumption.
To further clarify advantages and features of the present invention, a more particular
description of the invention will be rendered by reference to specific embodiments thereof,
which is illustrated in the appended drawings. It is appreciated that these drawings depict
only typical embodiments of the invention and are therefore not to be considered limiting of
its scope. The invention will be described and explained with additional specificity and detail
with the accompanying drawings.
BRIEF DESCRIPTION OF FIGURES:
These and other features, aspects, and advantages of the present invention will become better
understood when the following detailed description is read with reference to the
accompanying drawings in which like characters represent like parts throughout the
drawings, wherein:
Figure 1 illustrates a method corresponding to an embodiment of the invention;
Figure 2 illustrates a device according to an embodiment of the invention;
Figure 3 illustrates a block-diagram representation of a dimmer circuit incorporating the
device as depicted in Fig. 2; and
Figure 4 a circuit diagram of the dimmer circuit as illustrated in Fig. 3.
Further, skilled artisans will appreciate that elements in the drawings are illustrated for
simplicity and may not have been necessarily been drawn to scale. For example, the flow
charts illustrate the method in terms of the most prominent steps involved to help to improve
understanding of aspects of the present invention. Furthermore, in terms of the construction
of the device, one or more components of the device may have been represented in the
drawings by conventional symbols, and the drawings may show only those specific details
that are pertinent to understanding the embodiments of the present invention so as not to
obscure the drawings with details that will be readily apparent to those of ordinary skill in the
art having benefit of the description herein.
DETAILED DESCRIPTION:
For the purpose of promoting an understanding of the principles of the invention, reference
will now be made to the embodiment illustrated in the drawings and specific language will be
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used to describe the same. It will nevertheless be understood that no limitation of the scope of
the invention is thereby intended, such alterations and further modifications in the illustrated
system, and such further applications of the principles of the invention as illustrated therein
being contemplated as would normally occur to one skilled in the art to which the invention
relates.
It will be understood by those skilled in the art that the foregoing general description and the
following detailed description are exemplary and explanatory of the invention and are not
intended to be restrictive thereof.
Reference throughout this specification to “an aspect”, “another aspect” or similar language
means that a particular feature, structure, or characteristic described in connection with the
embodiment is included in at least one embodiment of the present invention. Thus,
appearances of the phrase “in an embodiment”, “in another embodiment” and similar
language throughout this specification may, but do not necessarily, all refer to the same
embodiment.
The terms "comprises", "comprising", or any other variations thereof, are intended to cover a
non-exclusive inclusion, such that a process or method that comprises a list of steps does not
include only those steps but may include other steps not expressly listed or inherent to such
process or method. Similarly, one or more devices or sub-systems or elements or structures or
components proceeded by "comprises... a" does not, without more constraints, preclude the
existence of other devices or other sub-systems or other elements or other structures or other
components or additional devices or additional sub-systems or additional elements or
additional structures or additional components.
Unless otherwise defined, all technical and scientific terms used herein have the same
meaning as commonly understood by one of ordinary skill in the art to which this invention
belongs. The system, methods, and examples provided herein are illustrative only and not
intended to be limiting.
Embodiments of the present invention will be described below in detail with reference to the
accompanying drawings.
Now referring to Figure 1, the present invention describes a method of controlling operation
in a dimmer circuit: The method may be executed by a microcontroller or any other
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equivalent logic device. The method comprises procuring (step 102) at least two dimmer
levels and receiving a reference point detected within a first type of signal, which may be a
periodical signal (e.g. an AC signal, a square-shaped wave, and a saw-tooth wave, etc), or
even a non-periodical signal. Each of said dimmer levels are associated with an individual
electrical device and represent a value by which the electrical device may be dimmed. The
reference point may be a zero crossing detected within the AC signal by a zero cross detector.
Thereafter, a single source generates (step 104) a second type of signal for each of said at
least two dimmer levels and triggers pulses periodcally within each of the second type of
signals. Further in case of multiple dimmer levels, then the multiple dimmer levels are sorted
in an increasing or decreasing order and thereafter pulses within the signals corresponding to
each dimmer level are triggered simultaneously in real time or after a pre-defined time-gap
with respect to each other.
As far as simultaneous triggering of pulses is concerned, a pulse within each second type of
signal is triggered (step 104) periodically from said single source, alongside the occurrence of
a reference point within the first type of signal (or the AC signal) or a time interval after said
occurrence of the reference point. The width of pulse triggered within each second type of
signal is based on the respective dimmer level. Said single source is a generator implemented
within a microcontroller acting as a centralized controller. The generator generates each of
said second type of signal as a digital signal with a ‘1’ base and triggers said periodical pulses
of ‘0’within each of the second type of signal or vice versa.
Accordingly, while start of the pulse is simultaneously triggered across each of the second
type of signals, an end of the pulse is triggered sequentially across the second type of signals,
For example, for a dimmer level having a least value, the end of the pulse is triggered earliest
and for the dimmer level having the highest value, an end of the pulse is triggered last of all.
Further, with the arrival of a next reference point or zero crossing within the first type of
signal or the AC signal, the pulses are re-triggered, thereby leading to periodical occurrences
of pulses within the signal. Such mode of operation may also be referred to as forward phase
dimming.
Likewise, the non-simultaneous triggering of pulses is also implementable in respect of the
present invention to realize another operation mode known as reverse-phase dimming.
Herein, the triggering of pulses across the second type of signals is timed at different point of
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time after the zero crossing has been detected. For example, in case of the dimmer level
having the lowest values, the start of the pulse may be triggered farthest from the zero
crossing. On the other hand, in case of the dimmer level having the highest value, the start of
pulse is triggered nearest to the detected zero crossing. Yet, the end of the pulses across all of
the second type of signals is triggered simultaneously at the arrival of the next zero crossing
or a time interval after the arrival of the next zero crossing.
Further, the second type of signals comprising the periodical pulses are communicated (step
106) to respective dimmer units to cause generation of at least two dimmer signals. The
dimmer signal generation from the dimmer units is done through an AND-ing operation of
the first type of signal (e.g. AC signal) as subjected to the dimmer unit with the
corresponding second type of signal having the periodical pulses, such that each dimmer unit
produces a unique dimmer signal. As a result, the electrical device as connected to the
dimmer unit provides a luminosity in accordance with the dimmer level. This is due to the
fact that the dimmer signal when communicated to an electrical device causes at least a
portion of available AC energy, to reach said electrical device. Accordingly, in case the
dimmer level has been zero, AC energy in a complete form reaches the electrical device.
Now referring to Figure 2, a device (200) for controlling an operation in a dimmer circuit has
been explained, wherein the device (200) at least executes the method steps as described in
previous figure. The device comprises a procurement module (202) for executing the step
102. The procurement module (202) procures said dimmer levels through an in-built
generation of the two or more dimmer levels, or automatically accessing the dimmer levels
from a storage unit where such dimmer levels may have been pre-stored, or receiving the
dimmer levels as an input from an external source (say a communication module) that
provides the dimmer levels in digital format. Such input may be received through an
input/output means provided within the device (200).
Further, the device (200) includes a generator (204) for executing the step 104, and an output
module (206) that executes the step 106. The device (200) may be incorporated in the form of
a logic device and accordingly may correspond to a microcontroller implemented as a system
on chip through an ASIC (application specific integrated circuit) or an FPGA (field
programmable gate array). In addition,the device (200) may also act a microprocessor, or any
other computational unit known in the art. Further, the device (200) may operate under a
single thread mode of operation to trigger pulses within at least two second type of signals,
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such that the device require interrupts for its functionality only during the course of triggering
the pulses that is based upon the occurrence of the referencepoint in the first type of signal. In
other words, only the triggering of pulses (whether along-with with the occurrence of the
reference point or after a time delay) is accomplished through interrupts or subroutines. Yet,
in another example, the device (200) may also operate under multi-threading mode of
operation.
In addition, the second type of signals having the periodical pulses may be configured to
cause both forward-phase dimming, through a simultaneous triggering of all the pulses at the
arrival of the zero crossing, as well as reverse-phase dimming through non-simultaneously
triggering the pulses within the signals after the arrival of the zero crossing.
Now referring to Fig. 3, a block diagram representation of a dimmer circuit (300)
incorporating the microcontroller as depicted in Fig. 2 has been illustrated. The dimmer
circuit (300) comprises a source for providing a first type of signal, e.g. an AC signal source
(302), a detector for detecting at least one reference point within the first type of signal, i.e. a
zero detector circuit (304) to detect zero-crossing within the AC signal, the microcontroller
(200) and a plurality of dimmer units (306) connected to said microcontroller (200). While
the zero detector circuit (304) communicates zero crossings, detected within the first type of
signal or the AC signal as the reference points to the microcontroller (200),a communication
module can communicate the dimmer levels to the microcontroller (200) through the I/O pin
of the microcontroller (200). Alternatively, the dimmer levels may either be pre-stored within
a memory accessible by the microcontroller (200) or generated by the microcontroller (200)
automatically. Further, the microcontroller (200) sends the generated second type of signals
having the periodical pulses to the corresponding dimmer units (306), which upon receiving
the second type of signals having the periodical pulses further generate corresponding
dimmer signals.
Now referring to Fig. 4, a circuit diagram of the dimmer circuit (300) of Fig. 3 has been
illustrated. Within the dimmer circuit (300), a power supply (i.e. AC to DC adapter) 402 to
the microcontroller (e.g. implemented as an FPGA logic circuit or as an ASIC) (200) draws
the supply from AC mains and conditions it to an appropriate voltage as per the requirements
of the microcontroller (200). As already elaborated with respect to Fig. 1, the microcontroller
(200) retrieves zero-cross values from a zero cross detector (404) and different dimmer
levels. The microcontroller (200) then processes the both received inputs to produce digital
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signals having pulses (or dips) having a width proportional to the dimmer levels, wherein the
dips or pulses are synchronized with the zero crossings as outputs DIM1, DIM2, DIM3……
The dimmer units (406) may be a combination of an opto-isolator and TRIAC or SCR
(Silicon Controlled Rectifier). The dimmer units (406) output an ANDing of DIM ’i’ signal
and the AC signal, thereby altering the input AC power signal, and generating a number of
control signal simultaneously to be provided to an array of electrical devices such as tube
lights, bulbs, CFLs (Compact fluorescent lamp), LEDs (Light emitting diodes), etc.
As a result, the present invention obviates the needs of multiple logic devices to control
dimming of different loads requiring different dimmer levels and provides at least a
centralized controlling mechanism. In addition, the present invention prescribes a
substantially simple dimmer circuit for controlling multiple loads, the simple dimmer circuit
being low on costs associated with manufacturing and maintenance.
Further, the present invention also provides an ease of retrofitting an existing electrical
system in a household or industry with a dimming system, through providing a centralized
dimming mechanism. In an example, the present invention as a device 200 may be mounted
within or as a part of a main distribution box/switchboard of a complex or as a part of
different distribution boxes/switchboards that are dedicated to each storey of a multi-storey
building. Nonetheless, the device 200 may also also be mounted within or as a part of each
individual switchboard or wherever a controlling mechanism for collection of switches is
already located or required. In other words, through centralizing the dimmer circuit in a
housing complex as a part of retrofitting, the present invention substantially minimizes
dismantling of existing fixtures and reduces overhead.
While specific language has been used to describe the disclosure, any limitations arising on
account of the same are not intended. As would be apparent to a person in the art, various
working modifications may be made to the method in order to implement the inventive
concept as taught herein.
The drawings and the forgoing description give examples of embodiments. Those skilled in
the art will appreciate that one or more of the described elements may well be combined into
a single functional element. Alternatively, certain elements may be split into multiple
functional elements. Elements from one embodiment may be added to another embodiment.
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For example, orders of processes described herein may be changed and are not limited to the
manner described herein.
Moreover, the actions of any flow diagram need not be implemented in the order shown; nor
do all of the acts necessarily need to be performed. Also, those acts that are not dependent on
other acts may be performed in parallel with the other acts. The scope of embodiments is by
no means limited by these specific examples. Numerous variations, whether explicitly given
in the specification or not, such as differences in structure, dimension, and use of material,
are possible. The scope of embodiments is at least as broad as given by the following claims.
Benefits, other advantages, and solutions to problems have been described above with regard
to specific embodiments. However, the benefits, advantages, solutions to problems, and any
component(s) that may cause any benefit, advantage, or solution to occur or become more
pronounced are not to be construed as a critical, required, or essential feature or component
of any or all the claims.

We Claim:
1. A device (200) for controlling an operation in a dimmer circuit, said system (200)
comprising:
at least one procurement module (202) for procuring at least two dimmer levels and
receiving a reference point detection within a first type of signal
at least one pulse-generator (204) configured to trigger periodically a pulse within a
second type of signal for each of said at least two dimmer levels based upon the occurrence
of reference point within the first type of signal, wherein the width of pulse within each
second type of signal is based on the value of the respective dimmer level;
and
at least one output module (206) to communicate said second type of signals
comprising the periodical pulses respectively to at least two dimmer units to cause generation
of at least two dimmer signals.
2. The device (200) as claimed in claim 1, wherein said procurement module (202) procures
said dimmer levels through at least one of:
generation of said levels;
accessing said levels from a storage; and
receiving said levels as an input from an external source.
3. The device (200) as claimed in claim 1, wherein the first type of signal as received by said
procurement module (202) is at least one of
a periodical signal represented by one or more of an AC signal, a square-shaped wave,
and a saw-tooth wave; and
a non-periodical signal.
4. The device (200) as claimed in claim 1, wherein said dimmer unit comprises at least one or
more of an opto-isolator, and/or a triac or a silicon controller rectifier.
5. The device (200) as claimed in claim 1, wherein said detected reference point is a zero
crossing detected within the first type of signal by a zero cross detector.
6. The device (200) as claimed in claim 1, wherein said device (200) is at least one of
microcontroller, a logic circuit, an electronic circuit implemented through FPGA or ASIC
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scheme, and wherein said generator (204) generates each of said second type of signal as a
digital signal with a ‘1’ base and triggers said periodical pulses as ‘0’within the second type
of signal and vice-versa.
7. The device (200) as claimed in claim 5, wherein said pulse generator (202) uses only a
single-thread based mode of operation to trigger periodically at least two pulses within
second type of signals.
8. The device (200) as claimed in claim 1, wherein said dimming levels as procured are
arranged in an increasing or decreasing order by said procurement module (202) to enable
said generator (204) at periodically triggering pulses in the second type of signals through
least one of:
simultaneously triggering start of pulses in said second type of signals after a fixed
interval of the occurrence of the reference point and sequentially triggering an end of pulses
in said second type of signals in accordance with said increasing or decreasing order; and
sequentially triggering start of pulses in said second type of signals in accordance
with said increasing or decreasing order after the occurrence of reference point, and
simultaneously triggering an end of pulses in said second type of signals after a fixed interval
of the occurrence of next reference point within the first type of signal.
9. The device (200) as claimed in claim 1, wherein each of said dimmer units combine the
received second type of signals having the periodical pulses with said first type of signal to
produce a unique dimmer signal.
10. The device (200) as claimed in claim 8, wherein said dimmer signal when communicated
to an electrical device causes at least a portion of available AC energy to reach said electrical
device.
11. A method of controlling an operation in a dimmer circuit:
procuring (step 102) at least two dimmer levels and receiving a reference point detected
within a first type of signal;
triggering (step 104) periodically, from a single source, a pulse within a second type of
signal for each of said at least two dimmer levels based upon the occurrence of reference
point within the first type of signal, wherein the width of pulse within each second type of
signal is based on the value of the respective dimmer levels; and
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communicating (step 106) said second type of signals comprising the periodical pulses
to respective at least two dimmer units to cause generation of at least two dimmer signals.
12. A dimmer circuit (300) comprising:
a source (302) for providing a first type of signal ;
a detector circuit (304, 404) to detect at least one reference point within the first type of
signal
at least two dimmer units (306, 406); and
a microcontroller (200) configured to:
procure at least two dimmer levels and receive the detected reference points from
the detector circuit (304, 404);
trigger periodically a pulse within a second type of signal for each of said at least
two dimmer levels based upon the occurrence of the reference point, wherein the width
of pulse within each second type of signal is based on the value of the respective
dimmer levels; and
communicate said second type of signals comprising the periodical pulses to
respective at least two dimmer units (306, 406) to cause generation of at least two
dimmer signals.