Dimmer jitter correction
First Claim
1. A controller for controlling a lamp driver supplied with an output of a dimmer, said controller comprising:
- enabling element configured to enable said lamp driver at a start time and disable said lamp driver before the end of an active period of said dimmer;
wherein said enabling element is further configured to disable said lamp driver a first time period after said start time; and
further comprising;
calculating element configured to calculate a proposed new first time period, wherein said enabling element is further configured to adapt said first time period based on said proposed new first time period;
a sensing element configured to sense a passive period of said dimmer based on said output of said dimmer and transmit a signal indicating said passive period to said calculating element, wherein said calculating element is further configured to calculate said proposed new first time period based on said signal indicating said passive period and a signal indicating said first time period;
wherein said enabling element is further configured to supply said signal indicating said first time period; and
wherein said calculating element is further configured to determine a second time period between the end of said first time period and a point in time at which a mains voltage of said dimmer falls below a certain level, subtract said determined second time period from a reference time period and integrate a subtraction result to obtain said proposed new first time period.
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0 Petitions
Accused Products
Abstract
A controller and a method for controlling lamp drivers such as e.g. LED drivers for lamps having a fast response behavior such as e.g. LED lamps are proposed. They enable to substantially reduce or prevent a visible luminance flicker at such lamps when dimming the lamps with a conventional dimmer such as e.g. a phase cut dimmer. This can be achieved by switching off the lamp driver prematurely in such a way that a time jitter of a dimmer switching does not influence an on-time of the lamp driver. No bulky or expensive filters or capacitors are needed. Thus, a space-switch saving and/or inexpensive construction is enabled.
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Citations
14 Claims
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1. A controller for controlling a lamp driver supplied with an output of a dimmer, said controller comprising:
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enabling element configured to enable said lamp driver at a start time and disable said lamp driver before the end of an active period of said dimmer; wherein said enabling element is further configured to disable said lamp driver a first time period after said start time; and further comprising; calculating element configured to calculate a proposed new first time period, wherein said enabling element is further configured to adapt said first time period based on said proposed new first time period; a sensing element configured to sense a passive period of said dimmer based on said output of said dimmer and transmit a signal indicating said passive period to said calculating element, wherein said calculating element is further configured to calculate said proposed new first time period based on said signal indicating said passive period and a signal indicating said first time period; wherein said enabling element is further configured to supply said signal indicating said first time period; and wherein said calculating element is further configured to determine a second time period between the end of said first time period and a point in time at which a mains voltage of said dimmer falls below a certain level, subtract said determined second time period from a reference time period and integrate a subtraction result to obtain said proposed new first time period. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
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11. A method of controlling a lamp driver supplied with an output of a dimmer, said method comprising:
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enabling said lamp driver at a start time; and disabling said lamp driver before the end of an active period of said dimmer; wherein disabling said lamp driver before the end of an active period of said dimmer comprises disabling said lamp driver a first time period after said start time; and further comprising calculating a proposed new first time period and adapting said first time period based on said proposed new first time period; sensing a passive period of said dimmer based on said output of said dimmer; calculating said proposed new first time period based on said signal indicating said passive period and a signal indicating said first time period; and integrating an output of said lamp driver to produce an integration result; and adapting said first time period based on the integration result.
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12. A controller for controlling a lamp driver supplied with an output of a dimmer, said controller comprising:
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enabling element configured to enable said lamp driver at a start time and disable said lamp driver before the end of an active period of said dimmer; wherein said enabling element is further configured to disable said lamp driver a first time period after said start time; and further comprising; calculating element configured to calculate a proposed new first time period, wherein said enabling element is further configured to adapt said first time period based on said proposed new first time period; a sensing element configured to sense a passive period of said dimmer based on said output of said dimmer and transmit a signal indicating said passive period to said calculating element, wherein said calculating element is further configured to calculate said proposed new first time period based on said signal indicating said passive period and a signal indicating said first time period; and an integrating element configured to integrate an output of said lamp driver and supply said signal indicating said first time period based on an integration result. - View Dependent Claims (13, 14)
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Specification