LED tube lamp with operating modes compatible with electrical ballasts
First Claim
1. A light emitting diode (LED) tube lamp configured to receive an external driving signal, comprising:
- an LED module for emitting light, the LED module comprising an LED unit comprising an LED;
a rectifying circuit for rectifying the external driving signal to produce a rectified signal, the rectifying circuit having a first output terminal and a second output terminal for outputting the rectified signal;
a filtering circuit connected to the LED module, and configured to provide a filtered signal for the LED unit; and
a protection circuit for providing protection for the LED tube lamp, the protection circuit comprising;
a voltage divider comprising two elements connected in series between the first and second output terminals of the rectifying circuit, for producing a signal at a connection node between the two elements; and
a control circuit coupled to the connection node between the two elements, for receiving, and detecting a state of, the signal at the connection node,wherein the control circuit includes or is coupled to a switching circuit coupled to the rectifying circuit;
the control circuit is configured to be triggered by the detected state, upon the external driving signal being input to the LED tube lamp, to prevent the input external driving signal from resulting in an overcurrent condition to the LED tube lamp;
the switching circuit has a control terminal connected to the control circuit, and two other terminals connected to a reference voltage and the first output terminal respectively; and
when the input external driving signal has a state that would cause an overcurrent condition, the control circuit is triggered by the detected state of the signal at the connection node to output a signal to the control terminal to turn on or conduct the switching circuit, wherein the conducting state of the switching circuit eventually discontinues a current conduction through the LED unit.
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Accused Products
Abstract
A light emitting diode (LED) tube lamp configured to receive an external driving signal includes an LED module for emitting light, the LED module comprising an LED unit comprising an LED; a rectifying circuit for rectifying the external driving signal to produce a rectified signal, the rectifying circuit having a first output terminal and a second output terminal for outputting the rectified signal; a filtering circuit connected to the LED module, and configured to provide a filtered signal for the LED unit; and a protection circuit for providing protection for the LED tube lamp. The protection circuit includes a voltage divider comprising two elements connected in series between the first and second output terminals of the rectifying circuit, for producing a signal at a connection node between the two elements; and a control circuit coupled to the connection node between the two elements, for receiving, and detecting a state of, the signal at the connection node. The control circuit includes or is coupled to a switching circuit coupled to the rectifying circuit, and the switching circuit is configured to be triggered on or off by the detected state, upon the external driving signal being input to the LED tube lamp, to allow discontinuous current to flow through the LED unit.
89 Citations
27 Claims
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1. A light emitting diode (LED) tube lamp configured to receive an external driving signal, comprising:
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an LED module for emitting light, the LED module comprising an LED unit comprising an LED; a rectifying circuit for rectifying the external driving signal to produce a rectified signal, the rectifying circuit having a first output terminal and a second output terminal for outputting the rectified signal; a filtering circuit connected to the LED module, and configured to provide a filtered signal for the LED unit; and a protection circuit for providing protection for the LED tube lamp, the protection circuit comprising; a voltage divider comprising two elements connected in series between the first and second output terminals of the rectifying circuit, for producing a signal at a connection node between the two elements; and a control circuit coupled to the connection node between the two elements, for receiving, and detecting a state of, the signal at the connection node, wherein the control circuit includes or is coupled to a switching circuit coupled to the rectifying circuit; the control circuit is configured to be triggered by the detected state, upon the external driving signal being input to the LED tube lamp, to prevent the input external driving signal from resulting in an overcurrent condition to the LED tube lamp; the switching circuit has a control terminal connected to the control circuit, and two other terminals connected to a reference voltage and the first output terminal respectively; and when the input external driving signal has a state that would cause an overcurrent condition, the control circuit is triggered by the detected state of the signal at the connection node to output a signal to the control terminal to turn on or conduct the switching circuit, wherein the conducting state of the switching circuit eventually discontinues a current conduction through the LED unit. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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13. A light emitting diode (LED) tube lamp configured to receive an external driving signal, comprising:
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an LED module for emitting light, the LED module comprising an LED unit comprising an LED; a rectifying circuit for rectifying the external driving signal to produce a rectified signal, the rectifying circuit having a first output terminal and a second output terminal for outputting the rectified signal; a filtering circuit connected to the LED module, and configured to provide a filtered signal for the LED unit; and a detection circuit coupled between the rectifying circuit and the LED module, the detection circuit comprising; a voltage divider comprising two elements connected in series between the first and second output terminals of the rectifying circuit, for producing a signal at a connection node between the two elements; and a control circuit coupled to the connection node between the two elements, for receiving, and detecting a state of, the signal at the connection node, wherein the control circuit includes or is coupled to a switching circuit coupled to the rectifying circuit, wherein the switching circuit has a control terminal connected to the control circuit and has two other terminals connected to a reference voltage and the first output terminal respectively, and wherein the detection circuit is configured such that when the external driving signal is input to the LED tube lamp, for preventing an overcurrent condition the control circuit is triggered by the detected state to output a signal to a control terminal of the switching circuit to turn on or conduct the switching circuit, wherein the conducting state of the switching circuit eventually discontinues a current conduction through the LED unit. - View Dependent Claims (14, 15, 16)
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17. A light emitting diode (LED) tube lamp configured to receive an external driving signal, comprising:
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a lamp tube; a first external connection terminal and a second external connection terminal coupled to the lamp tube and for receiving the external driving signal; an LED module for emitting light, the LED module comprising an LED unit comprising an LED; a rectifying circuit for rectifying the external driving signal to produce a rectified signal, the rectifying circuit having a first output terminal and a second output terminal for outputting the rectified signal; a filtering circuit coupled to the rectifying circuit and the LED module; a detection circuit coupled between the rectifying circuit and the LED module, the detection circuit comprising; a voltage divider comprising two elements connected in series between the first and second output terminals of the rectifying circuit, for producing a fraction voltage at a connection node between the two elements; and a controller coupled to the connection node between the two elements, for receiving the fraction voltage at the connection node; and a converter circuit coupled between the controller and the LED module, for converting a signal from the controller or the rectifying circuit into a driving signal for driving the LED module, wherein the controller includes or is coupled to a switch coupled to the converter circuit, wherein the switch has a control terminal connected to the controller and has two other terminals connected to a reference voltage and the first output terminal respectively, and wherein the detection circuit is configured for preventing an overcurrent condition and configured such that when the fraction voltage is in a defined voltage range, the controller regulates the continuity of current to flow through the LED unit by alternately turning on and off the switch; and
the controller is configured to be triggered by the fraction voltage to output a signal to the control terminal to turn on or conduct the switch, wherein the conducting state of the switch eventually discontinues a current conduction through the LED unit. - View Dependent Claims (18, 19, 20, 21, 22, 23, 24, 25, 26, 27)
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Specification