Patent ID: 8596108
Filing Date: 2013-12-03
Classification: G01N,Y10T

Abstract:
1. A gas measuring device for measuring a presence of a target gas in a fluid medium, the gas measuring device comprising: a sensor having a sensing element and a heating element being configured to heat the sensing element to a predetermined operating temperature, the sensing element being responsive to the target gas such that at least one electrical property of the sensing element varies based on a presence of the target gas, wherein the electrical property of the sensing element is measured by the gas measuring device; and a control circuit having a heating element controller connected to, and measuring an electrical property of, the heating element, and the control circuit having a heater power supply supplying power to the heating element, wherein the heating element controller is connected to, and controls the operation of, the heater power supply using pulse modulation based on the measurement of the electrical property of the heating element, and wherein the heating element controller controls the heater power supply using a first set of power pulses having a first duration and using a second set of power pulses having a second duration that is different than the first duration to maintain the electrical property of the heating element at a substantially constant value.