# US 2014/0197154 A1 · Resistance determination with increased sensitivity for temperature control of heated automotive components > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0197154 A1 - Document ID: US20140197154A1 - Status: Published application - Kind: A1 - Application number: 14/135,089 - Filed: 2013-12-19 - Published: 2014-07-17 - Earliest claimed: 2012-12-31 - Assignees: Continental Automotive Systems, Inc. - Applicants: Continental Automotive Systems, Inc. - Inventors: Perry Robert Czimmek - Web page: https://patentgrep.com/patent/US20140197154A1 ## CPC - G05D 23/1919: {characterised by the type of controller} - G05D 23/2401: {using a heating element as a sensing element} - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES ## Abstract Electrical resistance of a heated component is determined for temperature control and monitoring. A voltage-representation signal, which is proportional to a voltage across a heater component, is received. A magnified voltage-representation signal is generated by determining a difference between a voltage baseline offset, which represents a minimum operating voltage of the heater component, and the voltage-representation signal. A current-representation signal, which is proportional to an electrical current passing through the heater component is received. A magnified current-representation signal is generated by determining a difference between a current baseline offset, which represents a minimum operating current of the heater component, and the current-representation signal. The magnified current-representation signal is modulated to generate a resistance-representation signal that is proportional to an amount of modulation that makes the magnified current-representation signal approximately equal to the magnified voltage-representation signal. ## Claims ### Claim 1 A method comprising: receiving a voltage-representation signal that is proportional to a voltage across a heater component; generating a magnified voltage-representation signal by determining a difference between a voltage baseline offset, which represents a minimum operating voltage of the heater component, and the voltage-representation signal; receiving a current-representation signal that is proportional to an electrical current passing through the heater component; generating a magnified current-representation signal by determining a difference between a current baseline offset, which represents a minimum operating current of the heater component, and the current-representation signal; and modulating the magnified current-representation signal to generate a resistance-representation signal that is proportional to an amount of modulation that makes the magnified current-representation signal approximately equal to the magnified voltage-representation signal. ### Claim 2 (depends on 1) The method of claim 1, wherein the modulation is pulse-width modulation. ### Claim 3 (depends on 2) The method of claim 2, wherein the resistance-representation signal is generated, at least in part, based on a signal that is proportional to the percent duty cycle of the pulse width modulation. ### Claim 4 (depends on 1) The method of claim 1, wherein a difference of the resistance-representation signal and the magnified voltage-representation signal is integrated to provide an error signal configured to control the modulation such that the modulation is proportional to an electrical resistance of the heater component. ### Claim 5 (depends on 1) The method of claim 1, wherein a difference of the resistance-representation signal and the magnified voltage-representation signal is provided as an error signal configured to control the modulation such that the modulation is proportional to an electrical resistance of the heater component. ### Claim 6 (depends on 1) The method of claim 1, wherein the resistance-representation signal is scaled such that the resistance-representation signal is proportional to the electrical resistance of the heater component. ### Claim 7 (depends on 1) The method of claim 1, wherein the current-representation signal is generated by a differential voltage measurement of a voltage across a resistor that is passing an amount of current that is, proportionally, approximately the same as an amount of current passing through the heater component. ### Claim 8 (depends on 1) The method of claim 1, wherein the voltage-representation signal is generated by a differential voltage measurement of the heater component. ### Claim 9 Apparatus comprising: a low-pass filter that is configured to receive a modulated magnified current-representation signal that is proportional to a difference between a current baseline offset and an electrical current passing through a heater component and that is configured to provide a resistance-representation signal; an amplifier configured to generate a difference error signal based on a difference between a magnified voltage-representation signal, which is proportional to a difference between a voltage baseline offset and a voltage across a heater component, and the resistance-representation signal; and a modulator configured to modulate the magnified current-representation signal in response to the difference error signal such that the resistance-representation signal is proportional to an amount of modulation that makes the magnified current-representation signal approximately equal to the magnified voltage-representation signal. ### Claim 10 (depends on 9) The apparatus of claim 9, wherein the modulator is a pulse-width modulator. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein the magnified resistance-representation signal is generated, at least in part, based on a signal that is proportional to the percent duty cycle of the pulse-width modulator. ### Claim 12 (depends on 9) The apparatus of claim 9, wherein the amplifier is configured to integrate the difference of the magnified resistance-representation signal and the magnified voltage-representation such that the modulation is proportional to an electrical resistance of the heater component. ### Claim 13 (depends on 9) The apparatus of claim 9, wherein the amplifier is configured such that the modulation is proportional to an electrical resistance of the heater component. ### Claim 14 (depends on 9) The apparatus of claim 9, wherein the resistance-representation signal is scaled such that the resistance-representation signal is proportional to the electrical resistance of the heater component. ### Claim 15 (depends on 9) The apparatus of claim 9, wherein the current-representation signal is generated by a differential voltage measurement of a voltage across a resistor that is passing an amount of current that is, proportionally, approximately the same as an amount of current passing through the heater component. ### Claim 16 (depends on 9) The apparatus of claim 9, wherein the voltage-representation signal is generated by a differential voltage measurement of the heater component.