# US 10,312,703 B2 · Battery charging system with power path switch control > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,312,703 B2 - Document ID: US10312703B2 - Status: Granted - Kind: B2 - Application number: 14/930,519 - Filed: 2015-11-02 - Published: 2016-04-28 - Granted: 2019-06-04 - Earliest claimed: 2011-08-17 - Assignees: Texas Instruments Incorporated - Applicants: National Semiconductor Corporation - Inventors: Sanjay Gurlahosur - Web page: https://patentgrep.com/patent/US10312703B2 ## CPC - H02J 7/92: with prioritisation of loads or sources - H02J 7/18: due to variation of ohmic resistance in field circuit, using resistance switching in or out of circuit step by step - H02J 7/663: {using battery or load disconnect circuits (H02J9/002 takes precedence)} - H02J 7/933: {the cycle being controlled or terminated in response to electric parameters} - H02J 7/94: in response to battery current - H02J 7/96: in response to battery voltage - H02M 1/08: Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - 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 A battery charger circuit having a regulator controller configured to control the switching transistors of a switching voltage regulator. A power path switch is disposed intermediate an output of the switching voltage regulator and a terminal of a battery to be charged, with the power path switch including at least two transistor segments having common respective drain electrodes, common respective source electrodes and separate respective gate electrodes. A power path switch controller operates to sequentially turn ON the at least two transistor segments of the power path switch, preferably in the order of a decreasing ON resistance. ## Claims ### Claim 1 A battery charger circuit comprising: an input terminal; and an output terminal; a switch coupled between the input terminal and the output terminal, the switch including at least two transistor segments having common drain electrodes, common source electrodes and separate gate electrodes, the at least two transistor segments having different channel resistances; current detection circuitry configured to detect a short circuit condition based on a detected current of the switch exceeding a predefined threshold current; and a controller responsive to the detection of the short circuit condition, configured to successively turn off the at least two transistor segments until the detected current is below the predefined threshold current. ### Claim 2 (depends on 1) The battery charger circuit of claim 1 wherein the at least two transistor segments include at least four transistor segments having common drain electrodes, common source electrodes and separate gate electrodes. ### Claim 3 (depends on 1) The battery charger circuit of claim 1, wherein the controller responsive to the detection of the short circuit condition, is configured to successively turn off the at least two transistor segments until the detected current is below the predefined threshold current for a pre-defined period. ### Claim 4 (depends on 1) The battery charger circuit of claim 1, wherein the at least two transistor segments include at least four transistor segments having at least a first channel resistance, a second channel resistance greater than the first channel resistance, a third channel resistance greater than the second channel resistance, and a fourth channel resistance greater than the third channel resistance. ### Claim 5 (depends on 1) The battery charger circuit of claim 1, wherein the controller responsive to the detection of the short circuit condition, is configured to successively turn off the at least two transistor segments, in a sequence based on the channel resistances of the at least two transistor segments, until the detected current is below the predefined threshold current. ### Claim 6 (depends on 1) The battery charger of claim 1, wherein the at least two transistor segments include at least four transistor segments having at least a first channel resistance, a second channel resistance two times of the first channel resistance, a third channel resistance two times of the second channel resistance, and a fourth channel resistance two times of the third channel resistance. ### Claim 7 A battery charging system, comprising: a switching regulator; a battery; and a battery charge circuit including: a switch coupled between the switching regulator and the battery, the switch including at least two transistor segments having common drain electrodes, common source electrodes and separate gate electrodes, the at least two transistor segments having different channel resistances; current detection circuitry configured to detect a short circuit condition based on a detected current of the switch exceeding a predefined threshold current; and a controller responsive to the detection of the short circuit condition, configured to successively turn off the at least two transistor segments until the detected current is below the predefined threshold current. ### Claim 8 (depends on 7) The system of claim 7 wherein the at least two transistor segments include at least four transistor segments having common drain electrodes, common source electrodes and separate gate electrodes. ### Claim 9 (depends on 7) The system of claim 7, wherein the at least two transistor segments include at least four transistor segments having at least a first channel resistance, a second channel resistance two times of the first channel resistance, a third channel resistance two times of the second channel resistance, and a fourth channel resistance two times of the third channel resistance. ### Claim 10 (depends on 7) The system of claim 7, wherein the at least two transistor segments include at least four transistor segments having at least a first channel resistance, a second channel resistance greater than the first channel resistance, a third channel resistance greater than the second channel resistance, and a fourth channel resistance greater than the third channel resistance. ### Claim 11 (depends on 7) The system of claim 7, wherein the at least two transistor segments include at least four transistor segments, with the transistor segments having at least a first channel resistance, a second channel resistance greater than the first channel resistance, a third channel resistance greater than the second channel resistance, and a fourth channel resistance greater than the third channel resistance. ### Claim 12 (depends on 7) The system of claim 7, wherein the controller responsive to the detection of the short circuit condition, is configured to successively turn off the at least two transistor segments, in a sequence based on the channel resistances of the at least two transistor segments, until the detected current is below the predefined threshold current.