# US 8,786,211 B2 · Current control for SIMO converters > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,786,211 B2 - Document ID: US8786211B2 - Status: Granted - Kind: B2 - Application number: 13/327,495 - Filed: 2011-12-15 - Published: 2013-06-20 - Granted: 2014-07-22 - Earliest claimed: 2011-12-15 - Assignees: Cree, Inc. - Applicants: Michael Gilliom - Inventors: Michael Gilliom - Web page: https://patentgrep.com/patent/US8786211B2 ## CPC - H02M 3/1584: {with a plurality of power processing stages connected in parallel} - H05B 45/3725: Switched mode power supply [SMPS] - H05B 45/46: having LEDs disposed in parallel lines - H02M 3/1586: {switched with a phase shift, i.e. interleaved} - H05B 45/375: using buck topology - H05B 45/38: using boost topology - H05B 45/385: using flyback topology - Y02B 20/30: Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED] - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - 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 A system includes a single-inductor-multiple-out (SIMO) converter having storage circuitry in communication with a plurality of output channels, and a controller that controls and measures current flow through the SIMO converter. A signal generator may output switching signals to store current in the storage circuitry and discharge the stored current into the plurality of output channels. The discharged current may be measured and compared to a desired current draw through the output channels over a sample period. A compensator may determine whether to change one or more timing parameters used to control the flow of current through the SIMO converter. ## Claims ### Claim 1 A method of controlling current conduction in a single-inductor-multiple-output (SIMO) converter comprising storage circuitry in communication with a plurality of output channels, the method comprising: measuring, with at least one first controller, current drawn through the plurality of output channels over a current sample period, wherein the current sample period extends over multiple switching cycles, and wherein each of the plurality of output channels is configured to draw current during each of the multiple switching cycles; determining, with at least one second controller, whether to change an amount of current being conducted in the SIMO converter for a next sample period based on a comparison between the measured current drawn over the current sample period and a predetermined current draw. ### Claim 2 (depends on 1) The method of claim 1, wherein determining, with the at least one second controller, whether to change the amount of current being conducted for the next sample period comprises: determining whether to change at least one of a charge period or one or more channel conduction periods. ### Claim 3 (depends on 1) The method of claim 1, further comprising: determining, with at least one third controller, fixed channel conduction periods for the plurality of output channels for the current sample period. ### Claim 4 (depends on 1) The method of claim 1, further comprising: determining, with at least one third controller, one or more fixed ratios of channel conduction periods between the plurality of output channels for the current sample period. ### Claim 5 (depends on 4) The method of claim 4, further comprising: determining, with at least one fourth controller, whether to change one or more of the one or more fixed ratios of channel conduction periods based on the comparison, wherein determining whether to change one or more channel conduction periods is based on determining whether to change one or more of the one or more fixed ratios. ### Claim 6 (depends on 1) The method of claim 1, wherein the current sample period is over a quarter-cycle of a rectified alternating current (AC) input signal. ### Claim 7 (depends on 1) The method of claim 1, wherein the comparison of the measured current draw with the predetermined current draw comprises a comparison of a measured current draw with a predetermined current draw for each of the plurality of output channels. ### Claim 8 (depends on 1) The method of claim 1, further comprising: determining, with at least one third controller, a difference between the predetermined current draw and the measured current draw; and changing, with at least one fourth controller, the predetermined current draw for the next sample period based on the determined difference. ### Claim 9 (depends on 1) The method of claim 1, further comprising: increasing, with at least one third controller, at least one of a charge period or one or more channel conduction periods for the next sample period if the measured current draw through the plurality of output channels for the current sample period is less than the predetermined current draw; and decreasing, with at least one fourth controller, at least one of the charge period or one or more of the channel conduction periods for the next sample period if the measured current draw through the plurality of output channels for the current sample period is more than the predetermined current draw. ### Claim 10 (depends on 1) The method of claim 1, further comprising: determining, with at least one third controller, an arrangement of orders in which to discharge the stored current into the plurality of output channels over the plurality of switching cycles in the current sample period; and outputting, with at least one fourth controller, switching signals to draw the current through the output channels over the plurality of switching cycles in accordance with the arrangement. ### Claim 11 (depends on 10) The method of claim 10, wherein the arrangement comprises: a first order in which the plurality of output channels draw current during a current switching cycle of the plurality of switching cycles; and a second order in which the plurality of output channels draw current during a previous switching cycle of the plurality of switching cycles, wherein the second order is a reverse order of the first order. ### Claim 12 (depends on 10) The method of claim of claim 10, wherein the arrangement is determined for one of consolidated sequencing, interleaved sequencing, or commutated sequencing. ### Claim 13 (depends on 1) The method of claim 1, further comprising: determining, with at least one third controller, channel conduction periods for the current sample period for one of continuous current conduction or discontinuous current conduction. ### Claim 14 (depends on 1) The method of claim 1, wherein each of the plurality of output channels comprises a light emitting diode (LED) configured as a load of the output channel, wherein the predetermined current draw is a value based on a predetermined light output of the LEDs in the plurality of output channels. ### Claim 15 (depends on 14) The method of claim 14, further comprising: determining, with at least one third controller, whether to change the predetermined current draw based on a change in the predetermined light output. ### Claim 16 (depends on 1) The method of claim 1, further comprising: determining, with at least one third controller, whether to change one or more duty cycles of one or more signals sent to the SIMO converter to control the current conduction for the next sample period based on determining whether to change the amount of current being conducted. ### Claim 17 (depends on 1) The method of claim 1, wherein the first controller and the second controller are the same controller. ### Claim 18 (depends on 1) The method of claim 1, wherein the first controller and the second controller are different controllers. ### Claim 19 A controller system configured to control current conduction in a single-inductor-multiple output (SIMO) converter that comprises a plurality of output channels, the controller system comprising: an accumulator module that is configured to measure current drawn through the plurality of channels over a current sample period, wherein the current sample period extends over multiple switching cycles, and wherein each of the plurality of output channels is configured to draw current during each of the multiple switching cycles; and a compensator module that is configured to determine whether to change an amount of current being conducted in the SIMO converter for a next sample period based on a comparison between the measured current drawn and a predetermined current draw. ### Claim 20 (depends on 19) The controller system of claim 19, wherein the compensator module is configured to determine whether to change at least one of a charge period or one or more channel conduction periods based on the comparison. ### Claim 21 (depends on 19) The controller system of claim 19, further comprising a signal generator module that is configured to: determine fixed channel conduction periods for the plurality of output channels for the current sample period. ### Claim 22 (depends on 19) The controller system of claim 19, further comprising a signal generator module that is configured to: determine one or more fixed ratios of channel conduction periods between the plurality of output channels for the current sample period. ### Claim 23 (depends on 22) The controller system of claim 22, wherein the compensator module is further configured to: determine whether to change one or more of the one or more fixed ratios of channel conduction periods based on the comparison, wherein the determination of whether to change one or more channel conduction periods is based on a determination of whether to change one or more of the one or more fixed ratios. ### Claim 24 (depends on 19) The controller system of claim 19, wherein the current sample period is over a quarter-cycle of a rectified alternating current (AC) input signal. ### Claim 25 (depends on 19) The controller system of claim 19, further comprising a comparator module that is configured to compare a measured current draw with a predetermined current draw for each of the plurality of output channels to perform the comparison of the measured current draw with the predetermined current draw. ### Claim 26 (depends on 19) The controller system of claim 19, further comprising a comparator module that is configured to determine a difference between the measured current draw and the predetermined current draw, wherein the compensator module is configured to change the predetermined current draw for the next sample period based on the determined difference. ### Claim 27 (depends on 19) The controller system of claim 19, wherein the compensator module is further configured to: increase at least one of the charge period or one or more of the channel conduction periods for the next sample period if the measured current draw through the plurality of output channels for the current sample period is less than the predetermined current draw; and decrease at least one of the charge period or one or more of the channel conduction periods for the next sample period if the measured current draw through the plurality of output channels for the current sample period is more than the predetermined current draw. ### Claim 28 (depends on 19) The controller system of claim 19, further comprising a signal generator module that is configured to: determine an arrangement of orders in which to discharge the stored current into the plurality of output channels of the SIMO converter over a plurality of switching cycles in the current sample period; and output switching signals to draw the current through the output channels over the plurality of switching cycles in accordance with the arrangement. ### Claim 29 (depends on 28) The controller system of claim 28, wherein the arrangement comprises: a first order in which the plurality of output channels draw current during a current switching cycle of the plurality of switching cycles; and a second order in which the plurality of output channels draw current during a previous switching cycle of the plurality of switching cycles, wherein the second order is a reverse order of the first order. ### Claim 30 (depends on 28) The controller system of claim of claim 28, wherein the arrangement is determined for one of consolidated sequencing, interleaved sequencing, or commutated sequencing. ### Claim 31 (depends on 19) The controller system of claim 19, further comprising a signal generator module that is configured to: determine channel conduction periods for the current sample period for one of continuous current conduction or discontinuous current conduction. ### Claim 32 (depends on 19) The controller system of claim 19, wherein each of the plurality of output channels comprises a light emitting diode (LED) configured as a load of the output channel, wherein the desired current draw is a predetermined value based on a predetermined light output of the LEDs in the plurality of output channels. ### Claim 33 (depends on 32) The controller system of claim 32, wherein the compensator module is further configured to: determine whether to change the predetermined current draw based on a change in the predetermined light output. ### Claim 34 (depends on 19) The controller system of claim 19, wherein the compensator module is further configured to: determine whether to change one or more duty cycles of one or more signals sent to the SIMO converter to control the current conduction for the next sample period based on the determination of whether to change the amount of current being conducted. ### Claim 35 (depends on 19) The controller system of claim 19, wherein each of the plurality of output channels comprises a load, wherein one or more of the loads are floating with respect to ground. ### Claim 36 (depends on 35) The controller system of claim 35, wherein each of the plurality of output channels further comprises an output switch and a sense resistor in communication with the load, wherein at least one of the output switch and the sense resistor is referenced to a common ground. ### Claim 37 (depends on 19) The controller system of claim 19, wherein the SIMO converter comprises a flyback converter. ### Claim 38 (depends on 19) The controller system of claim 19, wherein the SIMO converter comprises a boost converter. ### Claim 39 (depends on 19) The controller system of claim 19, wherein the SIMO converter comprises a buck converter.