# US 12,771,230 B2 · Trapezoidal current mode for multilevel DC-DC converter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,771,230 B2 - Document ID: US12771230B2 - Status: Granted - Kind: B2 - Application number: 18/799,391 - Filed: 2024-08-09 - Published: 2026-01-22 - Granted: 2026-10-20 - Earliest claimed: 2024-07-22 - Assignees: Nanyang Technological University; Lite-On Singapore Pte. Ltd.; Lite-On Technology Corporation - Applicants: Nanyang Technological University; Lite-On Singapore Pte. Ltd.; Lite-On Technology Corporation - Inventors: Zhi-Gang Yao; Yi Tang; Jing Yang; Shih-Ming Chen; Jung-Chih Wei - Web page: https://patentgrep.com/patent/US12771230B2 ## CPC - H02M 1/0095: {Hybrid converter topologies, e.g. NPC mixed with flying capacitor, thyristor converter mixed with MMC or charge pump mixed with buck} - H02M 1/0058: {by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero (using an auxiliary actively switched resonant commutation circuit connected to an intermediate DC voltage or between two push-pull branches of an inverter bridge H02M7/4811; in resonant inverters H02M7/4815; in inverters operating from a resonant DC source H02M7/4826)} - H02M 3/07: using capacitors charged and discharged alternately by semiconductor devices with control electrode {, e.g. charge pumps} - H02M 3/158: including plural semiconductor devices as final control devices for a single load - 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) ## Abstract In an aspect of the disclosure, a pulse generator for applying to a multilevel DC-DC converter including a filter is provided. The pulse generator includes a controller and multiple capacitor-switch modules coupled to the controller and configured to receive an input voltage of the multilevel DC-DC converter and output an inductor current with a trapezoidal waveform on an inductor of the filter. ## Claims ### Claim 1 A pulse generator for applying to a multilevel DC-DC converter including a filter, comprising: a controller; and a plurality of capacitor-switch modules, coupled to the controller and configured to receive an input voltage of the multilevel DC-DC converter and output an inductor current with a trapezoidal waveform on an inductor of the filter, wherein the controller measures the input voltage, the output voltage and the inductor current of the multilevel DC-DC converter, calculates three duty cycles, and assigns the three duty cycles to the plurality of capacitor-switch modules to generate a pulse-width modulation (PWM), wherein the PWM correspondingly forms a three level sequence of an output voltage of the pulse generator, and the three level sequence of the output voltage of the pulse generator correspondingly forms the inductor current with the trapezoidal waveform on the inductor of the filter. ### Claim 2 (depends on 1) The pulse generator of claim 1, wherein the trapezoidal waveform on the inductor of the filter is with reverse peak current compared to an average inductor current, wherein when an output current of the multilevel DC-DC converter is greater than zero, the inductor current has two positive peak currents and one negative valley current during the duty cycles. ### Claim 3 (depends on 2) The pulse generator of claim 2, wherein the duty cycles are sequentially corresponding to an n-level, an x-level and a 0-level, of an output voltage of the pulse generator, wherein the n-level of the output voltage of the pulse generator is higher than the x-level of the output voltage of the pulse generator, and the x-level of the output voltage of the pulse generator is higher than the 0-level of the output voltage of the pulse generator. ### Claim 4 (depends on 3) The pulse generator of claim 3, wherein the n-level of the output voltage of the pulse generator is corresponding to a rising edge of the trapezoidal waveform, wherein the x-level of the output voltage of the pulse generator is corresponding to a positive peak period of the trapezoidal waveform, wherein the 0-level of the output voltage of the pulse generator is corresponding to a falling edge of the trapezoidal waveform. ### Claim 5 (depends on 1) The pulse generator of claim 1, wherein the trapezoidal waveform on the inductor of the filter is with positive peak current compared to an average inductor current, wherein when an output current of the multilevel DC-DC converter is less than zero, the inductor current includes two negative valley currents and one positive peak current during the duty cycles. ### Claim 6 (depends on 5) The pulse generator of claim 5, wherein the duty cycles are sequentially corresponding to a 0-level, an x-level and an n-level, of an output voltage of the pulse generator, wherein the 0-level of the output voltage of the pulse generator is less than the x-level of the output voltage of the pulse generator, and the x-level of the output voltage of the pulse generator is less than the n-level of the output voltage of the pulse generator. ### Claim 7 (depends on 6) The pulse generator of claim 6, wherein the 0-level of the output voltage of the pulse generator is corresponding to a falling edge of the trapezoidal waveform, wherein the x-level of the output voltage of the pulse generator is corresponding to a negative peak period of the trapezoidal waveform, wherein the n-level of the output voltage of the pulse generator is corresponding to a rising edge of the trapezoidal waveform. ### Claim 8 (depends on 1) The pulse generator of claim 1, wherein the plurality of capacitor-switch modules include four serially connected capacitor-switch modules, and each of the four parallel connected capacitor-switch modules includes a complementary pair of switches and one capacitor, wherein a gate of each switch of the four parallel connected capacitor-switch modules is coupled to the controller to receive the duty cycles. ### Claim 9 (depends on 1) The pulse generator of claim 1, wherein the plurality of capacitor-switch modules include three parallelly connected capacitor-switch modules, and each of the three parallel connected capacitor-switch modules includes a complementary pair of switches and one capacitor, wherein a gate of each switch of the three parallelly connected capacitor-switch modules is coupled to the controller to receive the duty cycles. ### Claim 10 (depends on 1) The pulse generator of claim 1, wherein the plurality of capacitor-switch modules include four capacitor-switch modules with midpoint clamps and flying capacitors, and each of the four capacitor-switch modules includes a complementary pair of switches and one capacitor, wherein a gate of each switch of the three parallelly connected capacitor-switch modules is coupled to the controller to receive the duty cycles. ### Claim 11 A method for outputting an inductor current with the trapezoidal waveform of a multilevel DC-DC converter, comprising: measuring, by a controller, an input voltage, an output voltage and the inductor current of the multilevel DC-DC converter; calculating, by the controller, three duty cycles; and assigning, by the controller, the three duty cycles to a plurality of capacitor-switch modules of a pulse generator of the multilevel DC-DC converter to generate a pulse-width modulation (PWM), wherein the PWM correspondingly forms a three level sequence of an output voltage of the pulse generator, and the three level sequence of the output voltage of the pulse generator correspondingly forms the inductor current with the trapezoidal waveform on an inductor of a filter of the multilevel DC-DC converter. ### Claim 12 (depends on 11) The method of claim 11, wherein the trapezoidal waveform on the inductor of the filter is with reverse peak current compared to an average inductor current, wherein when an output current of the multilevel DC-DC converter is greater than zero, the inductor current includes two positive peak currents and one negative valley current during the duty cycles. ### Claim 13 (depends on 12) The method of claim 12, wherein the duty cycles are sequentially corresponding to an n-level, an x-level and a 0-level, of an output voltage of the pulse generator, wherein the n-level of the output voltage of the pulse generator is higher than the x-level of the output voltage of the pulse generator, and the x-level of the output voltage of the pulse generator is higher than the 0-level of the output voltage of the pulse generator. ### Claim 14 (depends on 13) The method of claim 13, wherein the n-level of the output voltage of the pulse generator is corresponding to a rising edge of the trapezoidal waveform, wherein the x-level of the output voltage of the pulse generator is corresponding to a positive peak period of the trapezoidal waveform, wherein the 0-level of the output voltage of the pulse generator is corresponding to a falling edge of the trapezoidal waveform. ### Claim 15 (depends on 11) The method of claim 11, wherein the trapezoidal waveform on the inductor of the filter is with positive peak current compared to an average inductor current, wherein when an output current of the multilevel DC-DC converter is less than zero, the inductor current includes two negative valley currents and one positive peak current during the duty cycles. ### Claim 16 (depends on 15) The pulse generator of claim 15, wherein the duty cycles are sequentially corresponding to a 0-level, an x-level and an n-level, of an output voltage of the pulse generator, wherein the 0-level of the output voltage of the pulse generator is less than the x-level of the output voltage of the pulse generator, and the x-level of the output voltage of the pulse generator is less than the n-level of the output voltage of the pulse generator. ### Claim 17 (depends on 16) The pulse generator of claim 16, wherein the 0-level of the output voltage of the pulse generator is corresponding to a falling edge of the trapezoidal waveform, wherein the x-level of the output voltage of the pulse generator is corresponding to a negative peak period of the trapezoidal waveform, wherein the n-level of the output voltage of the pulse generator is corresponding to a rising edge of the trapezoidal waveform. ### Claim 18 (depends on 11) The method of claim 11, wherein the plurality of capacitor-switch modules include four serially connected capacitor-switch modules, and each of the four parallel connected capacitor-switch modules includes a complementary pair of switches and one capacitor, wherein a gate of each switch of the four parallel connected capacitor-switch modules is coupled to the controller to receive the duty cycles. ### Claim 19 (depends on 11) The method of claim 11, wherein the plurality of capacitor-switch modules include three parallelly connected capacitor-switch modules, and each of the three parallel connected capacitor-switch modules includes a complementary pair of switches and one capacitor, wherein a gate of each switch of the three parallelly connected capacitor-switch modules is coupled to the controller to receive the duty cycles. ### Claim 20 (depends on 11) The method of claim 11, wherein the plurality of capacitor-switch modules include four capacitor-switch modules with midpoint clamps and flying capacitors, and each of the four capacitor-switch modules includes a complementary pair of switches and one capacitor, wherein a gate of each switch of the three parallelly connected capacitor-switch modules is coupled to the controller to receive the duty cycles.