# US 2018/0323781 A1 · Isolation and Voltage Regulation Circuit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0323781 A1 - Document ID: US20180323781A1 - Status: Published application - Kind: A1 - Application number: 15/773,462 - Filed: 2016-10-25 - Published: 2018-11-08 - Earliest claimed: 2015-11-03 - Assignees: Intelligent Energy Limited - Applicants: Intelligent Energy Limited - Inventors: Brendan DEVANEY; Stephen LAWES - Web page: https://patentgrep.com/patent/US20180323781A1 ## CPC - H03K 17/30: Modifications for providing a predetermined threshold before switching (shaping pulses by thresholding H03K5/08) - H01M 8/043: applied during specific periods - H01M 8/0488: {of fuel cell stacks} - H01M 8/04953: {of auxiliary devices, e.g. batteries, capacitors} - H02J 1/108: having arrangements for blocking reverse current flow, e.g. using diodes (H02J1/12 takes precedence) - H03K 17/302: {in field-effect transistor switches} - H02J 1/106: {for load balancing, symmetrisation, or sharing} - H03K 2017/307: {circuits simulating a diode, e.g. threshold zero} - Y02E 60/50: Fuel cells - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract The disclosure relates to an isolation and voltage regulation circuit for an electrochemical power source, the circuit comprising: an input terminal (202) for coupling to the power source and receiving an input voltage (Vin) from the power source; an output terminal (204) for coupling to a load; a diode circuit (206) connected between the input terminal and the output terminal; a diode controller (208) configured to control electrical conduction through the diode circuit between the input terminal and the output terminal, the diode controller having a first controller input (210) coupled to the output terminal and a second controller input (212); and a reference controller (220) configured to set a voltage at the second controller input (212) in accordance with a comparison between the input voltage (Vin) and a reference voltage (Vref). ## Claims ### Claim 1 An isolation and voltage regulation circuit for an electrochemical power source, the circuit comprising: an input terminal for coupling to the power source and for receiving an input voltage from the power source; an output terminal for coupling to a load; a diode circuit connected between the input terminal and the output terminal; a diode controller configured to control electrical conduction through the diode circuit between the input terminal and the output terminal, the diode controller having a first controller input coupled to the output terminal and a second controller input; and a reference controller configured to set a voltage at the second controller input in accordance with a comparison between the input voltage and a reference voltage. ### Claim 2 (depends on 1) The circuit of claim 1 in which the reference controller is coupled between the input terminal and the second controller input. ### Claim 3 (depends on 2) The circuit of claim 2 in which the reference controller is configured to set the voltage at the second controller input by switchably coupling the second controller input to (i) a reference voltage source when the input voltage is greater than the reference voltage and (ii) the input terminal when the input voltage is less than the reference voltage. ### Claim 4 (depends on 3) The circuit of claim 3 in which the reference controller is configured to couple the second controller input to the input terminal when the input voltage is equal to the reference voltage. ### Claim 5 (depends on 3) The circuit of claim 3 in which the reference controller comprises selection circuitry configured to select whether the input voltage or the reference voltage is provided as a second voltage to the second controller input of the diode controller. ### Claim 6 (depends on 5) The circuit of claim 5 in which the reference controller comprises a reference comparator with a first reference input, a second reference input and a reference output, the first reference input is connected to the input terminal in order to receive the input voltage, the second reference input is connected to the reference voltage source in order to receive the reference voltage, and a signal from the reference output is provided to control the selection circuitry. ### Claim 7 (depends on 1) The circuit of claim 1 in which the diode controller has a first controller input, a second controller input and a controller output and is configured to drive the controller output to maintain a voltage equal to the reference voltage. ### Claim 8 (depends on 1) The circuit of claim 1 in which the diode circuit comprises a switchable element. ### Claim 9 (depends on 8) The circuit of claim 8 in which the switchable element is a field effect transistor. ### Claim 10 (depends on 8) The circuit of any claim 8 in which the diode circuit comprises a pair of switchable elements connected between the input terminal and the output terminal, and in which the control circuit is coupled to the pair of switchable elements. ### Claim 11 (depends on 1) The system comprising the isolation and voltage regulation circuit of claim 1 and an electrochemical power source connected to the input terminal of the isolation and voltage regulation circuit. ### Claim 12 (depends on 11) The system of claim 11 in which the electrochemical power source comprises a fuel cell. ### Claim 13 A method of operating an isolation and voltage regulation circuit for an electrochemical power source, the circuit comprising: an input terminal coupled to the power source and receiving an input voltage from the power source; an output terminal coupled to a load; a diode circuit connected between the input terminal and the output terminal; a diode controller controlling electrical conduction through the diode circuit between the input terminal and the output terminal, the diode controller having a first controller input coupled to the output terminal and a second controller input; and a reference source providing a reference voltage, the method comprising: comparing the input voltage and the reference voltage setting a voltage at the second controller input in accordance with a result of the comparison. ### Claim 14 (depends on 13) The method of claim 13 comprising setting the voltage at the second controller input as: the reference voltage when the input voltage is greater than the reference voltage; and the input voltage when the input voltage is less than the reference voltage. ### Claim 15 A circuit, system, controller or method substantially as described herein with reference to the accompanying drawings.