# US 8,541,951 B1 · High temperature LED system using an AC power source > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,541,951 B1 - Document ID: US8541951B1 - Status: Granted - Kind: B1 - Application number: 13/298,905 - Filed: 2011-11-17 - Granted: 2013-09-24 - Earliest claimed: 2010-11-17 - Assignees: Soraa, Inc. - Applicants: Frank Tin Chung Shum; Frank M. Steranka; Cliff Jue - Inventors: Frank Tin Chung Shum; Frank M. Steranka; Cliff Jue - Web page: https://patentgrep.com/patent/US8541951B1 ## CPC - H05B 45/44: with an active control inside an LED matrix - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL ## Abstract Power management and thermal management for high intensity LED lamps are disclosed. ## Claims ### Claim 1 An LED system for coupling to an AC power source comprising: a rectifier module being electrically coupled to the AC power source, the rectifier module being configured to provide a rectified output; a first array of LED devices, the first array of LED devices being electrically coupled to the rectifier module and to receive the rectified output; a second array of LED devices electrically coupled to the first array of LED devices; a current monitor module electrically coupled to the first array and second array of LED devices, the current monitor module being configured to determine a first current level using a drawn current level signal associated with the first array of LED devices and a second current level using a reference current level signal associated with the second array of LED devices; and a signal compensating module electrically coupled to the current monitor module, the signal compensating module being configured to generate a first compensation factor signal based on a difference between the first current level and a first reference current level. ### Claim 2 (depends on 1) The system of claim 1 further comprising a low pass filter electrically coupled to the current monitor module and the signal compensating module. ### Claim 3 (depends on 1) The system of claim 1 wherein the first array of LED devices is electrically coupled to the second array of LED devices in series. ### Claim 4 (depends on 1) The system of claim 1 further comprising a first switch and a second switch, the first switch being configured to control the first array of LED devices in response to the compensation factor signal. ### Claim 5 (depends on 1) The system of claim 1 wherein the signal compensating module comprises a divider module. ### Claim 6 (depends on 1) The system of claim 1 wherein the signal compensating module comprises a differential operational amplifier. ### Claim 7 (depends on 1) The system of claim 1 wherein the rectifier module is mounted to a printed circuit board. ### Claim 8 (depends on 1) The system of claim 1, further comprising: an LED submount having a front surface and a back surface, the front surface comprising an inner region and an outer region, the inner region being characterized by a reflectivity of at least 80%, the first and second arrays of LED devices being disposed on the inner region. ### Claim 9 (depends on 8) The system of claim 8 wherein the first and second array of LED devices are configured for being operable at 100 degrees Celsius or higher. ### Claim 10 (depends on 8) The system of claim 8 further comprising: a heat sink directly coupled to the back surface of the LED submount, the heat sink being characterized by a thermal emissivity of at least 0.5. ### Claim 11 (depends on 10) The system of claim 10 wherein the outer region of the heat sink is substantially non-reflective. ### Claim 12 (depends on 10) The system of claim 10 further comprising an MR-16 housing. ### Claim 13 (depends on 10) The system of claim 10 wherein the outer region of the heat sink is coated with anodized aluminum material and characterized by a thermal emissivity of at least 0.8. ### Claim 14 (depends on 10) The system of claim 10 wherein the heat sink is coated by a non-reflective material, a surface of the heat sink being characterized by an emissivity of at least 0.9. ### Claim 15 (depends on 10) The system of claim 10 wherein at least 10% of the front surface area is characterized an emissivity of 0.6 or greater. ### Claim 16 (depends on 10) The system of claim 10 further comprising a reflector positioned within an inner region of the front surface. ### Claim 17 (depends on 10) The system of claim 10 wherein a thermal resistance from the LED submount to the high-emissivity surface area is less than 8 C/W. ### Claim 18 (depends on 10) The system of claim 10 wherein the outer surface of the heat sink is coated by a substantially black coating. ### Claim 19 An LED system for coupling to an AC power source comprising: a rectifier module being electrically coupled to the AC power source, the rectifier module being configured to provide a rectified output; a first array of LED devices, the first array of LED devices being electrically coupled to the rectifier module and to receive the rectified output; a second array of LED devices electrically coupled to the first array of LED devices; a current monitor module electrically coupled to the first array and second array of LED devices, the current monitor module being configured to determine a first current level using a drawn current level signal associated with the first array of LED devices and a second current level using a reference current level signal associated with the second array of LED devices; a signal compensating module electrically coupled to the current monitor module, the signal compensating module being configured to generate a first compensation factor signal based on a difference between the first current level and a first reference current level; and an LED submount having a front surface and a back surface, the front surface comprising an inner region and an outer region, the inner region being characterized by a reflectivity of at least 80%. ### Claim 20 An LED system for coupling to an AC power source comprising: a rectifier module being electrically coupled to the AC power source, the rectifier module being configured to provide a rectified output; a first array of LED devices, the first array of LED devices being electrically coupled to the rectifier module and to receive the rectified output; a second array of LED devices electrically coupled to the first array of LED devices; a current monitor module electrically coupled to the first array and second array of LED devices, the current monitor module being configured to determine a first current level using a drawn current level signal associated with the first array of LED devices and a second current level using a reference current level signal associated with the second array of LED devices; a signal compensating module electrically coupled to the current monitor module, the signal compensating module being configured to generate a first compensation factor signal based on a difference between the first current level and a first reference current level; an LED submount having a front surface and a back surface, the front surface comprising an inner region and an outer region, the inner region being characterized by a reflectivity of at least 80% the first and second arrays of LED devices being disposed on the inner region; and a heat sink coupled to at the LED submount the heat sink being characterized by a thermal emissivity of at least 0.5.