# US 2017/0257918 A1 · Universal led driver switching circuit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0257918 A1 - Document ID: US20170257918A1 - Status: Published application - Kind: A1 - Application number: 15/449,300 - Filed: 2017-03-03 - Published: 2017-09-07 - Earliest claimed: 2016-03-04 - Assignees: Basic6, Inc. - Applicants: Basic6 Inc. - Inventors: Victor ANSART; John STEIN; Magnus WENNEMYR - Web page: https://patentgrep.com/patent/US20170257918A1 ## CPC - H04B 10/116: Visible light communication - H04B 10/502: {LED transmitters} - H04B 10/516: Details of coding or modulation - H05B 45/10: Controlling the intensity of the light - H05B 45/3725: Switched mode power supply [SMPS] - H05B 45/375: using buck topology - H05B 45/38: using boost topology - H05B 47/175: by remote control - Y02B 20/30: Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED] - H04B: TRANSMISSION - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract Apparatus including a light emitting diode; a constant current source for driving the diode; modulation circuitry for modulating the current supplied to the light emitting diode so that digital information can be carried on light from the diode; and a filtering circuit between the constant current source and the light emitting diode to minimize the effect of LED modulation on the current source. Alternatively, the constant current source can supply current to the diode or to one of a power dissipating element or power storage element. A method for powering a light emitting diode includes using a constant current source; and modulating the current supplied by the constant current source at a frequency for transmitting digital data on light produced. In the alternative, a method can also include diverting current from the constant current source away from the light emitting diode, when the light emitting diode is not emitting light. ## Claims ### Claim 1 An apparatus comprising: a light emitting diode; a constant current source for driving the light emitting diode; modulation circuitry to modulate the current supplied to the light emitting diode by the constant current source at a rate sufficient so that digital information is carried on light emitted by the light emitting diode, wherein the modulation circuitry includes at least one of a microcontroller and a microprocessor; and filtering circuitry to minimize voltage and current oscillations experienced by the constant current source when modulating the current supplied to the light emitting diode, whereby the constant current source functions normally and outputs a substantially constant current, and wherein the filtering circuit contains at least one power storing element to store energy provided by the constant current source when the light emitting diode is off, and wherein the component supplies the energy to the light emitting diode when the light emitting diode is on. ### Claim 2 (depends on 1) The apparatus of claim 1, further comprising communication circuitry for allowing the at least one of the microcontroller and the microprocessor to communicate via a network. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the filtering circuit is selected from the group consisting of a pi filter, a T filter, an RC filter and an active filter. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the filtering circuit is a pi filter. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the filtering circuitry maintains the lifetime or reliability of the constant current source ### Claim 6 (depends on 1) The apparatus of claim 1, disposed in an adapter to be used to provide power from a source to a light emitting diode. ### Claim 7 An apparatus comprising: a light emitting diode; a constant current source for driving the light emitting diode; modulation circuitry to modulate the current supplied to the light emitting diode by the constant current source at a rate sufficient so that digital information is carried on light emitted by the light emitting diode, wherein the modulation circuitry includes: at least one of a microcontroller and a microprocessor; a first switching element for supplying power to the light emitting diode; a power storing element; and a second switching element for supplying current to the power storing element; wherein only one of the first switching element and the second switching element supply power at a given time, so that the current supplied by the constant current source remains substantially constant. ### Claim 8 (depends on 7) The apparatus of claim 7, further comprising communication circuitry for allowing the at least one of the microcontroller and the microprocessor to communicate via a network. ### Claim 9 (depends on 7) The apparatus of claim 7, wherein the one of a microcontroller and a microprocessor acts as a modulation signal source for supplying a modulation signal to one of the first switching element and the second switching element, further comprising: a logic inverter for supplying an inverted form of the modulation signal to another of the first switching element and the second switching element. ### Claim 10 (depends on 9) The apparatus of claim 9, wherein only one of the first switching element and the second switching element supply power at a given time. ### Claim 11 (depends on 7) The apparatus of claim 7, wherein the power storing element is a capacitor, further comprising a voltage regulator circuit for regulating the voltage produced across the capacitor. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the voltage regulator circuit includes a boost converter if the voltage in the capacitor is below a predetermined voltage. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein the voltage regulator circuit includes a buck converter if the voltage in the capacitor is above a predetermined voltage. ### Claim 14 (depends on 11) The apparatus of claim 11, wherein the voltage regulator circuit includes a buck-boost converter if the voltage in the capacitor is at times below and at times above a predetermined voltage. ### Claim 15 (depends on 7) The apparatus of claim 7, disposed in an adapter to be used to provide power from a source to a light emitting. ### Claim 16 (depends on 7) The apparatus of claim 7, packaged as a self-contained unit for connection to a power source. ### Claim 17 (depends on 7) The apparatus of claim 7, wherein power stored in the power storing element is used to power related circuitry performing tasks other than control and signal modulation ### Claim 18 A method for powering a light emitting diode, comprising: using a constant current source to power the light emitting diode; and modulating current supplied by the constant current source at a frequency for transmitting digital data on light produced by the light emitting diode; and using a filter circuit between the constant current source and the light emitting diode to so that voltage and current oscillations experienced by the constant current source when modulating the current supplied to the light emitting diode are reduced, whereby the constant current source functions normally and outputs a substantially constant current. ### Claim 19 A method for powering a light emitting diode, comprising: using a constant current source to power the light emitting diode; modulating current supplied by the constant current source at a frequency for transmitting digital data on light produced by the light emitting diode; and diverting current from the constant current source away from the light emitting diode, when the light emitting diode is modulated to not emit light; wherein the current is diverted to one of an energy dissipating and an energy storage device.