# US 2021/0242771 A1 · Multi-mode dc-to-dc power converter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0242771 A1 - Document ID: US20210242771A1 - Status: Published application - Kind: A1 - Application number: 16/778,697 - Filed: 2020-01-31 - Published: 2021-08-05 - Earliest claimed: 2020-01-31 - Assignees: QUALCOMM Incorporated - Applicants: Qualcomm Incorporated - Inventors: Jiwei Chen; Guoyong Guo; Yue Jing - Web page: https://patentgrep.com/patent/US20210242771A1 ## CPC - 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 - G06F 1/263: {Arrangements for using multiple switchable power supplies, e.g. battery and AC (G06F1/30 takes precedence)} - H02J 7/865: {Battery or charger load switching, e.g. concurrent charging and load supply (H02J7/50 takes precedence)} - H02J 7/90: Regulation of charging or discharging current or voltage - H02M 1/36: Means for starting or stopping converters - H02J 2207/20: Charging or discharging characterised by the power electronics converter - H02M 3/072: {adapted to generate an output voltage whose value is lower than the input voltage} - Y02B 70/10: Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes - 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) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract An apparatus is disclosed for implementing a multi-mode direct-current (DC)-to-DC power converter. In an example aspect, the apparatus includes a DC-to-DC power converter with a flying capacitor, an inductor, and four switches. The inductor is coupled between a second node and a battery node. A first switch is coupled between a first node and a first terminal of the flying capacitor. A second switch is coupled between the first terminal and the second node. A third switch is coupled between a second terminal of the flying capacitor and the second node. A fourth switch is coupled between the second terminal and a ground node. The DC-to-DC power converter is configured to selectively transfer power from the first node to the battery node according to a first operational mode and transfer other power from the battery node to the first node according to a second operational mode. ## Claims ### Claim 1 An apparatus comprising: a direct-current (DC)-to-DC power converter comprising: a first node, a second node, a battery node, and a ground node; a flying capacitor having a first terminal and a second terminal; an inductor coupled between the second node and the battery node; a first switch coupled between the first node and the first terminal of the flying capacitor; a second switch coupled between the first terminal of the flying capacitor and the second node; a third switch coupled between the second terminal of the flying capacitor and the second node; and a fourth switch coupled between the second terminal of the flying capacitor and the ground node, the DC-to-DC power converter configured to selectively: transfer power from the first node to the battery node according to a first operational mode; and transfer other power from the battery node to the first node according to a second operational mode. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the DC-to-DC power converter is configured to selectively: operate as a three-level buck converter according to the first operational mode; and operate as a two-level boost converter according to the second operational mode. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein: the DC-to-DC power converter is configured to selectively operate as a divide-by-two charge pump to transfer the power from the first node to the battery node according to a third operational mode; and the DC-to-DC power converter comprises a bypass switch coupled between the second node and the battery node, the bypass switch configured to selectively be: in a closed state based on the third operational mode; and in an open state based on the first operational mode or the second operational mode. ### Claim 4 (depends on 1) The apparatus of claim 1, further comprising: a control circuit coupled to the DC-to-DC power converter, the control circuit configured to enable the DC-to-DC power converter to transition between the first operational mode and the second operational mode, wherein: the DC-to-DC power converter comprises a capacitor coupled between the first node and a ground; and the DC-to-DC power converter is configured to selectively: operate in a soft-start state during the second operational mode to adjust a voltage across the flying capacitor while at least one of the first switch or the fourth switch is in the open state; or operate in a steady state during the second operational mode such that the flying capacitor is connected in parallel to the capacitor. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the control circuit comprises: a soft-start circuit coupled to the first terminal of the flying capacitor and the second terminal of the flying capacitor, the soft-start circuit configured to adjust the voltage across the flying capacitor based on a voltage at the first node, the voltage across the flying capacitor, and a reference voltage; and a driver circuit coupled to the first switch and the fourth switch, the driver circuit configured to selectively: cause at least one of the first switch or the fourth switch to be in the open state during the soft-start state; and cause both the first switch and the fourth switch to be in a closed state during the steady state. ### Claim 6 (depends on 5) The apparatus of claim 5, wherein the control circuit comprises: a voltage sensor coupled to the first terminal of the flying capacitor and the second terminal of the flying capacitor, the voltage sensor configured to measure the voltage across the flying capacitor; and a comparator coupled to the voltage sensor, the first node, the reference voltage, and the driver circuit, the comparator configured to cause the driver circuit to transition from operating the DC-to-DC power converter in the soft-start state to operating the DC-to-DC power converter in the steady state responsive to an absolute value of a difference between the voltage at the first node and the voltage across the flying capacitor being less than the reference voltage. ### Claim 7 (depends on 5) The apparatus of claim 5, wherein the driver circuit is coupled to the second switch and the third switch, and the driver circuit is configured to cause, responsive to the voltage at the first node being less than another reference voltage: the first switch and the second switch to alternate between the open state and the closed state according to a first signal during the soft-start state; and the third switch and the fourth switch to alternate between the open state and the closed state according to a second signal during the soft-start state, a phase difference between the first signal and the second signal being approximately 180 degrees. ### Claim 8 (depends on 5) The apparatus of claim 5, wherein the driver circuit is configured to cause, responsive to the voltage at the first node being greater than another reference voltage, the first switch, the second switch, the third switch, and the fourth switch to be in the closed state during the soft-start state. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein: the battery node is configured to be coupled to a battery; the ground node is configured to be coupled to a ground; and the first node is configured to be selectively coupled to: a power source based on the DC-to-DC power converter being in the first operational mode; and an external load based on the DC-to-DC power converter being in the second operational mode. ### Claim 10 (depends on 1) The apparatus of claim 1, wherein: the battery node is configured to be selectively: coupled to a load based on the DC-to-DC power converter being in the first operational mode; and coupled to a battery based on the DC-to-DC power converter being in the second operational mode. ### Claim 11 (depends on 1) The apparatus of claim 1, wherein: the load comprises at least one processor and a display screen; and the DC-to-DC power converter is configured to transfer the power to the at least one processor and the display screen. ### Claim 12 An apparatus comprising: a first node configured to selectively couple to a power source or an external load; a battery node configured to be coupled to a battery; and direct-current (DC)-to-DC power conversion means for selectively operating as a three-level buck converter to transfer power from the first node to the battery node and as a two-level boost converter to transfer other power from the battery node to the first node. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the DC-to-DC power conversion means comprises: capacitive means for storing and releasing a first portion of energy, the capacitive means having a first terminal and a second terminal; inductive means for storing and releasing a second portion of energy, the inductive means coupled between a second node and the battery node; and switching means for transferring the first portion of energy and the second portion of energy between the first node and the battery node, the switching means comprising: first means for selectively operating in a closed state to connect the first node to the first terminal or an open state to disconnect the first node from the first terminal; second means for selectively operating in the closed state to connect the first terminal to the second node or the open state to disconnect the first terminal from the second node; third means for selectively operating in the closed state to connect the second terminal to the second node or disconnecting the second terminal from the second node; and fourth means for selectively operating in the closed state to connect the second terminal to a ground node or the open state to disconnect the second terminal from the ground node. ### Claim 14 (depends on 13) The apparatus of claim 13, further comprising: current means for adjusting an amount of the first portion of energy stored by the capacitive means during a soft-start state in which the DC-to-DC power conversion means operates as the two-level boost converter; and driver means for controlling at least the first means or the fourth means to operate in the open state during the soft-start state. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein the driver means is configured to control the first means and the fourth means to operate in the closed state to connect the capacitive means between the first node and the ground node during a steady state in which the DC-to-DC power conversion means operates as the two-level boost converter. ### Claim 16 (depends on 14) The apparatus of claim 14, wherein the driver means is configured to control, responsive to a voltage at the first node being less than a reference voltage: the first means and the second means to alternate between the closed state and the open state according to a first phase during the soft-start state; and the third means and the fourth means to alternate between the closed state and the open state according to a second phase during the soft-start state, a difference between the first phase and the second phase being approximately 180 degrees. ### Claim 17 (depends on 14) The apparatus of claim 14, wherein the driver means is configured to control, responsive to a voltage at the first node being greater than a reference voltage, the first means, the second means, the third means, and the fourth means to be in the closed state during the soft-start state. ### Claim 18 A method comprising: connecting a first node of a direct-current (DC)-to-DC power converter to a power source; operating the DC-to-DC power converter as a three-level buck converter according to a first operational mode; transferring power from the power source to a battery responsive to the DC-to-DC power converter operating as the three-level buck converter; connecting the first node of the DC-to-DC power converter to an external load; operating the DC-to-DC power converter as a two-level boost converter according to a second operational mode; and transferring other power from the battery to the external load responsive to the DC-to-DC power converter operating as the two-level boost converter. ### Claim 19 (depends on 18) The method of claim 18, wherein the operating the DC-to-DC power converter as the two-level boost converter comprises: adjusting, during a soft-start state, a voltage across a flying capacitor of the DC-to-DC power converter while at least one of a first terminal of the flying capacitor is disconnected from the first node or a second terminal of the flying capacitor is disconnected from a ground node of the DC-to-DC power converter; and connecting the flying capacitor between the first node and the ground node during a steady state. ### Claim 20 (depends on 19) The method of claim 19, wherein the operating the DC-to-DC power converter as the two-level boost converter comprises transitioning from the soft-start state to the steady state responsive to an absolute value of a difference between a voltage at the first node and the voltage across the flying capacitor being less than a reference voltage. ### Claim 21 (depends on 19) The method of claim 19, wherein the operating the DC-to-DC power converter as the two-level boost converter comprises alternating between connecting an inductor of the DC-to-DC power converter to the first node and connecting the inductor to the ground node during the steady state. ### Claim 22 (depends on 19) The method of claim 19, wherein the operating the DC-to-DC power converter as the two-level boost converter comprises: responsive to a voltage at the first node being less than a reference voltage, alternating between connecting an inductor of the DC-to-DC power converter to the first node and connecting the inductor to the ground node during the soft-start state; and responsive to the voltage at the first node being greater than the reference voltage, disconnecting the inductor from the first node and the ground node during the soft-start state. ### Claim 23 An apparatus comprising: a first power path configured to be connected to a power source; a second power path configured to be connected to an external load; a battery; a switching circuit coupled between the first power path, the second power path, and a first node, the switching circuit configured to selectively: connect the first node to the first power path; and connect the first node to the second power path; and a direct-current (DC)-to-DC power converter comprising: the first node; and a battery node coupled to the battery, the DC-to-DC power converter configured to selectively: operate as a three-level buck converter to transfer power from the first power path to the battery according to a first operational mode; and operate as a two-level boost converter to transfer other power from the battery to the second power path according to a second operational mode. ### Claim 24 (depends on 23) The apparatus of claim 23, wherein the DC-to-DC power converter comprises: a second node and a ground node; a flying capacitor having a first terminal and a second terminal; an inductor coupled between the second node and the battery node; a first switch coupled between the first node and the first terminal of the flying capacitor; a second switch coupled between the first terminal of the flying capacitor and the second node; a third switch coupled between the second terminal of the flying capacitor and the second node; and a fourth switch coupled between the second terminal of the flying capacitor and the ground node. ### Claim 25 (depends on 24) The apparatus of claim 24, wherein the DC-to-DC power converter is further configured to selectively operate as a divide-by-two charge pump to transfer the power from the power source to the battery according to a third operational mode. ### Claim 26 (depends on 25) The apparatus of claim 25, wherein the DC-to-DC power converter comprises a bypass switch coupled between the second node and the battery node, the bypass switch configured to selectively be: in a closed state based on the third operational mode; and in an open state based on the first operational mode or the second operational mode. ### Claim 27 (depends on 24) The apparatus of claim 24, further comprising a control circuit coupled to the DC-to-DC power converter, the control circuit configured to: cause the first switch and the second switch to alternate between an open state and a closed state according to a first signal during a soft-start state associated with the second operational mode; and cause the third switch and the fourth switch to alternate between the open state and the closed state according to a second signal during the soft-start state, a phase difference between the first signal and the second signal being approximately 180 degrees. ### Claim 28 (depends on 27) The apparatus of claim 27, wherein the control circuit comprises a soft-start circuit configured to adjust a voltage across the flying capacitor while the first switch is in the open state or the fourth switch is in the open state. ### Claim 29 (depends on 27) The apparatus of claim 27, wherein the control circuit is configured to cause the first switch and the fourth switch to be in the closed state during a steady state associated with the second operational mode. ### Claim 30 (depends on 29) The apparatus of claim 29, wherein the control circuit is configured to cause the DC-to-DC power converter to transition from the soft-start state to the steady state responsive to an absolute value of a difference between a voltage at the first node and a voltage across the flying capacitor being less than a reference voltage.