# US 11,028,973 B2 · Led tube lamp > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,028,973 B2 - Document ID: US11028973B2 - Status: Granted - Kind: B2 - Application number: 16/667,370 - Filed: 2019-10-29 - Published: 2020-08-27 - Granted: 2021-06-08 - Earliest claimed: 2015-03-10 - Assignees: Jiaxing Super Lighting Electric Appliance Co., Ltd - Applicants: Jiaxing Super Lighting Electric Appliance Co., Ltd - Inventors: Aiming Xiong; Xintong Liu; Junren Chen; Hechen Hu; Hao Zhang - Web page: https://patentgrep.com/patent/US11028973B2 ## CPC - F21K 9/278: Arrangement or mounting of circuit elements integrated in the light source - H05B 45/3578: Emulating the electrical or functional characteristics of discharge lamps - F21K 9/27: Retrofit light sources for lighting devices with two fittings for each light source, e.g. for substitution of fluorescent tubes - F21K 9/272: Details of end parts, i.e. the parts that connect the light source to a fitting; Arrangement of components within end parts (F21K9/278 takes precedence) - F21K 9/275: Details of bases or housings, i.e. the parts between the light-generating element and the end caps; Arrangement of components within bases or housings (F21K9/278 takes precedence) - F21V 3/061: {the material being glass} - F21V 15/015: Devices for covering joints between adjacent lighting devices; End coverings - F21V 23/003: {the elements being electronics drivers or controllers for operating the light source, e.g. for a LED array} - F21V 23/005: {the substrate is supporting also the light source} - F21V 23/023: {Power supplies in a casing (F21V23/003 takes precedence)} - F21V 25/00: Safety devices structurally associated with lighting devices (gas- tight or water-tight arrangements F21V31/00; in general F16P; protective circuit arrangements per se H02H7/00) - F21V 25/02: coming into action when lighting device is disturbed, dismounted, or broken - F21V 25/04: breaking the electric circuit - F21V 29/70: characterised by passive heat-dissipating elements, e.g. heat-sinks - H05B 45/00: Circuit arrangements for operating light-emitting diodes [LED] - H05B 45/10: Controlling the intensity of the light - H05B 45/20: Controlling the colour of the light - H05B 45/37: Converter circuits - H05B 45/50: responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits - H05B 45/59: for reducing or suppressing flicker or glow effects - H05B 47/17: Operational modes, e.g. switching from manual to automatic mode or prohibiting specific operations - H05K 1/00: Printed circuits - H05K 1/14: Structural association of two or more printed circuits (providing electric connection to or between printed circuits H05K1/11, H01R12/00) - F21V 23/02: the elements being transformers, impedances {or power supply units, e.g. a transformer with a rectifier} - F21V 29/83: the elements having apertures, ducts or channels, e.g. heat radiation holes - F21Y 2103/10: comprising a linear array of point-like light-generating elements - F21Y 2115/10: Light-emitting diodes [LED] - H05K 1/147: {at least one of the printed circuits being bent or folded, e.g. by using a flexible printed circuit (H05K1/148 takes precedence)} - H05K 2201/10106: Light emitting diode [LED] - Y02B 20/30: Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED] - F21K: NON-ELECTRIC LIGHT SOURCES USING LUMINESCENCE; LIGHT SOURCES USING ELECTROCHEMILUMINESCENCE; LIGHT SOURCES USING CHARGES OF COMBUSTIBLE MATERIAL; LIGHT SOURCES USING SEMICONDUCTOR DEVICES AS LIGHT-GENERATING ELEMENTS; LIGHT SOURCES NOT OTHERWISE PROVIDED FOR - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS - F21Y: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A power supply module is configured to provide, based on an external driving signal, a driving current for driving an LED tube lamp. The power supply module includes a detection path circuit, configured to establish a detection path which is capable of affecting an electrical signal on a power line of the power supply module when the detection path is turned on, and a driving circuit, electrically connected to the detection path circuit, and configured to produce the driving current based on the external driving signal. When the driving circuit is activated by receiving the external driving signal, the driving circuit enters into a first mode to detect whether a foreign external impedance is electrically connected to the LED tube lamp. When the foreign external impedance is detected, the driving circuit remains in the first mode, and when the foreign external impedance is not detected, the driving circuit enters into a second mode to produce the driving current. The driving circuit is further configured to obtain a dimming message from the electrical signal and adjust the magnitude of the driving current according to the dimming message when in the second mode. ## Claims ### Claim 1 A power supply module configured to provide, based on an external driving signal, a driving current for driving an LED tube lamp, comprising: a detection path circuit, configured to establish a detection path which is capable of affecting an electrical signal on a power line of the power supply module when the detection path is turned on; and a driving circuit, electrically connected to the detection path circuit, and configured to produce the driving current based on the external driving signal, wherein when the driving circuit is activated by receiving the external driving signal, the driving circuit enters into a first mode to detect whether a foreign external impedance is electrically connected to the LED tube lamp, wherein when the foreign external impedance is detected, the driving circuit remains in the first mode, and when the foreign external impedance is not detected, the driving circuit enters into a second mode to produce the driving current, and wherein the driving circuit is further configured to obtain a dimming message from the electrical signal and adjust the magnitude of the driving current according to the dimming message when in the second mode. ### Claim 2 (depends on 1) The power supply module according to claim 1, wherein the driving circuit comprises: a driving controller, electrically connected to the detection path circuit for receiving the electrical signal; and a conversion circuit, electrically connected to the driving controller and configured to produce the driving current in response to the control of the driving controller. ### Claim 3 (depends on 1) The power supply module according to claim 1, further comprising: a rectifying circuit, having input terminals for receiving the external driving signal and output terminals; and a filtering circuit, having input terminals electrically connected to the output terminals of the rectifying circuit and output terminals electrically connected to the driving circuit. ### Claim 4 (depends on 3) The power supply module according to claim 3, wherein the detection path circuit comprises: a first diode, having an anode electrically connected to one of the input terminals of the rectifying circuit and a cathode; a second diode, having an anode electrically connected to another one of the input terminals of the rectifying circuit and a cathode electrically connected to the cathode of the first diode; and a transistor, having a first terminal electrically connected to the cathode of the first and the second diodes, a second terminal electrically connected to a ground terminal, and a control terminal configured to receive a pulse signal in the first mode. ### Claim 5 (depends on 3) The power supply module according to claim 3, wherein the detection path circuit comprises: a transistor, having a first terminal electrically connected to one of the output terminals of the rectifying circuit, a second terminal electrically connected to another one of the output terminals of the rectifying circuit, and a control terminal configured to receive a pulse signal in the first mode. ### Claim 6 A method for determining whether a foreign external impedance is electrically connected to an LED tube lamp, comprising: sampling a voltage on a detection path disposed in the LED tube lamp at a first point in time to obtain a first voltage level; issuing, after the first point in time, a pulse signal to temporarily turn on the detection path; sampling the voltage on the detection path at a second point in time to obtain a second voltage level, wherein the second point in time is within the period of the detection path being turned on; and generating an indication for indicating whether the foreign external impedance is electrically connected to the LED tube lamp according to the first voltage level and the second voltage level. ### Claim 7 (depends on 6) The method according to claim 6, wherein the step of generating a result for indicating whether the foreign external impedance is electrically connected to the LED tube lamp according to the first voltage level comprises: calculating a difference between the first voltage level and the second voltage level; comparing the difference with a set value; generating the indication with a first logic level for indicating the foreign external impedance is electrically connected to the LED tube lamp when the difference is greater than the set value; and generating the indication with a second logic level for indicating the foreign external impedance is not electrically connected to the LED tube lamp when the difference is not greater than the set value. ### Claim 8 (depends on 6) The method according to claim 6, wherein the step of generating a result for indicating whether the foreign external impedance is electrically connected to the LED tube lamp according to the first voltage level comprises: respectively comparing the first voltage level and the second voltage level with a set value; generating the indication with a first logic level for indicating the foreign external impedance is electrically connected to the LED tube lamp when the first voltage level and the second voltage level are not greater than the set value; and generating the indication with a second logic level for indicating the foreign external impedance is not electrically connected to the LED tube lamp when the first voltage level is not greater than the set value and the second voltage level is greater than the set value. ### Claim 9 (depends on 6) The method according to claim 6, wherein the step of generating a result for indicating whether the foreign external impedance is electrically connected to the LED tube lamp according to the first voltage level comprises: comparing the first voltage level with the second voltage level; generating the indication with a first logic level for indicating the foreign external impedance is electrically connected to the LED tube lamp when the first voltage level is greater than the second voltage level; and generating the indication with a second logic level for indicating the foreign external impedance is not electrically connected to the LED tube lamp when the first voltage level is not greater than the second voltage level. ### Claim 10 An LED tube lamp, comprising: a lamp tube; two end caps, connected to respective ends of the lamp tube; an LED light strip, mounted on an inner surface of the lamp tube; a plurality of LED chips, disposed on the LED light strip; and a power supply module, electrically connected to the LED chips via the LED light strip, and configured to drive the LED chips to emit light, wherein the power supply module comprises: a detection path circuit, configured to establish a detection path which is capable of affecting an electrical signal on a power line of the power supply module when the detection path is turned on; and a driving circuit, electrically connected to the detection path circuit, and configured to produce a driving current based on an external driving signal, wherein when the driving circuit is activated by receiving the external driving signal, the driving circuit enters into a first mode to detect whether a foreign external impedance is electrically connected to the LED tube lamp, wherein when the foreign external impedance is detected, the driving circuit remains in the first mode, and when the foreign external impedance is not detected, the driving circuit enters into a second mode to produce the driving current, and wherein the driving circuit is further configured to obtain a dimming message from the electrical signal and adjust the magnitude of the driving current according to the dimming message when in the second mode. ### Claim 11 (depends on 10) The LED tube lamp according to claim 10, wherein the driving circuit comprises: a driving controller, electrically connected to the detection path circuit for receiving the electrical signal; and a conversion circuit, electrically connected to the driving controller and configured to produce the driving current in response to the control of the driving controller. ### Claim 12 (depends on 10) The LED tube lamp according to claim 10, further comprising: a rectifying circuit, having input terminals for receiving the external driving signal and output terminals; and a filtering circuit, having input terminals electrically connected to the output terminals of the rectifying circuit and output terminals electrically connected to the driving circuit. ### Claim 13 (depends on 12) The LED tube lamp according to claim 12, wherein the detection path circuit comprises: a first diode, having an anode electrically connected to one of the input terminals of the rectifying circuit and a cathode; a second diode, having an anode electrically connected to another one of the input terminals of the rectifying circuit and a cathode electrically connected to the cathode of the first diode; and a transistor, having a first terminal electrically connected to the cathode of the first and the second diodes, a second terminal electrically connected to a ground terminal, and a control terminal configured to receive a pulse signal in the first mode. ### Claim 14 (depends on 12) The LED tube lamp according to claim 12, wherein the detection path circuit comprises: a transistor, having a first terminal electrically connected to one of the output terminals of the rectifying circuit, a second terminal electrically connected to another one of the output terminals of the rectifying circuit, and a control terminal configured to receive a pulse signal in the first mode. ### Claim 15 (depends on 10) The LED tube lamp according to claim 10, wherein the driving circuit determines whether the foreign external impedance is detected based on the following steps: sampling the electrical signal at a first point in time to obtain a first voltage level; issuing, after the first point in time, a pulse signal to temporarily turn on the detection path; sampling the electrical signal at a second point in time to obtain a second voltage level, wherein the second point in time is within the period of the detection path being turned on; determining the foreign external impedance is electrically connected to the LED tube lamp when the first voltage level is greater than the second voltage level; and determining the foreign external impedance is not electrically connected to the LED tube lamp when the first voltage level is not greater than the second voltage level.