# US 2014/0191741 A1 · Low current dc-dc converter with integrated low current coulomb counter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0191741 A1 - Document ID: US20140191741A1 - Status: Published application - Kind: A1 - Application number: 13/734,485 - Filed: 2013-01-04 - Published: 2014-07-10 - Earliest claimed: 2013-01-04 - Assignees: Linear Technology Corporation - Applicants: Linear Technology Corporation - Inventors: Samuel H. NORK - Web page: https://patentgrep.com/patent/US20140191741A1 ## CPC - H02J 7/94: in response to battery current - G01R 29/24: Arrangements for measuring quantities of charge - G05F 1/62: using bucking or boosting DC sources - H02M 3/156: with automatic control of output voltage or current, e.g. switching regulators - H02M 1/0032: {Control circuits allowing low power mode operation, e.g. in standby mode} - H02M 3/1582: {Buck-boost converters (H02M3/1584 takes precedence)} - 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 - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - G05F: SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES - 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) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A power supply system includes a regulator circuit responsive to an input signal at the input node for producing an output signal at the output node at a desired level. The regulator circuit has a controller, an inductive element and a first switch coupled to the inductor element and controlled by the controller to produce the output signal. Also, the power supply system includes a Coulomb counter for producing a Coulomb count signal proportional to the number of Coulombs passing from the input node to the output node. The Coulomb counter is enabled by an enabling signal representing a predetermined time period, for determining the number of Coulombs passing from the input node to the output node during that predetermined time period. ## Claims ### Claim 1 A power supply system having an input node and an output node, comprising: a regulator circuit responsive to an input signal at the input node for producing an output signal at the output node at a desired level, and having a controller, an inductive element and a first switch coupled to the inductor element and controlled by the controller to produce the output signal, and a Coulomb counter for producing a Coulomb count signal proportional to the number of Coulombs passing from the input node to the output node, the Coulomb counter being enabled by an enabling signal representing a predetermined time period, for determining the number of Coulombs passing from the input node to the output node during the predetermined time period. ### Claim 2 (depends on 1) The system of claim 1, wherein the enabling signal represents a time period during which the first switch is ON. ### Claim 3 (depends on 2) The system of claim 2, wherein the regulator circuit is configured to operate in a buck-boost mode. ### Claim 4 (depends on 2) The system of claim 2, wherein the regulator circuit is configured to operate in a buck mode. ### Claim 5 (depends on 1) The system of claim 1, wherein the regulator circuit is configured to operate in a boost mode and includes a second switch coupled to the inductor element. ### Claim 6 (depends on 5) The system of claim 5, wherein the enabling signal represents the sum of a first time period during which the first switch is ON and a second time period during which the second switch is ON. ### Claim 7 (depends on 1) The system of claim 1, wherein the Coulomb counter is configured for counting the number of Coulombs transferred to the output node from a battery coupled to the input node. ### Claim 8 (depends on 1) The system of claim 1, wherein the Coulomb counter is configured for counting the number of Coulombs transferred from the input node to a battery coupled to the output node. ### Claim 9 (depends on 2) The system of claim 2, wherein the Coulomb counter is enabled for determining the number of Coulombs during only one ON time period of the first switch out of a predetermined number of successive ON time periods of the first switch. ### Claim 10 (depends on 1) The system of claim 1, wherein the regulator circuit is configured for operating in a sleep mode when the output voltage is above a predetermined regulation point. ### Claim 11 (depends on 10) The system of claim 10, wherein circuitry for determining the number of Coulombs is not active when the regulator circuit is in a sleep mode. ### Claim 12 (depends on 1) The system of claim 1, wherein the Coulomb counter includes a Coulomb measuring circuit for determining the number of Coulombs passing from the input node to the output node during the predetermined time period to produce a value representing the determined number of Coulombs, and a result accumulating circuit for accumulating values produced by the Coulomb measuring circuit. ### Claim 13 (depends on 12) The system of claim 12, wherein an accumulated value in the result accumulating circuit represents total number of periods during which the first switch is ON. ### Claim 14 (depends on 1) The system of claim 1, wherein the regulator circuit and the Coulomb counter are integrated on a single integrated circuit. ### Claim 15 A method of supplying power from an input node to an output node, comprising the steps of: in response to an input signal at the input node, producing an output signal at an output node at a desired level, determining the number of Coulombs passing from the input node to the output node during a predetermined time period to produce a measurement value representing the number of Coulombs per the predetermined time period, and accumulating measurement values determined during a number of predetermined time periods to produce a Coulomb count signal representing the total number of Coulombs transferred from the input node to the output node. ### Claim 16 (depends on 15) The method of claim 15, wherein the output signal is produced by a regulator circuit having a first controllable switch, and the predetermined period represents an ON time period of the first controllable switch. ### Claim 17 (depends on 16) The method of claim 16, wherein the number of Coulombs is determined during only one ON time period of the first controllable switch out of a predetermined number of successive ON time periods of the first controllable switch. ### Claim 18 (depends on 15) The method of claim 15, wherein the output signal is produced by a regulator circuit having first and second controllable switches, and the predetermined period represents the sum of an ON time period of the first controllable switch and an ON time period of the second controllable switch.