Abstract: A temperature control system for an electrically heated cutaneous gas sensor. A heating element is provided with heating current by a closed loop temperature control circuit. The system includes a plurality of temperature monitoring circuits which are arranged to turn off the flow of heating current if the temperature of the sensor takes on an unacceptable value. The system also includes temperature setting circuitry for applying an increased temperature setpoint signal to the temperature control circuit, for a predetermined time, to reduce the time delay between the application of the sensor to the patient and the production of usable sensor data. Timing circuitry assures that the flow of heating current is not turned off in response to normal sensor temperature transients.

Abstract: A temperature control system for an electrically heated cutaneous gas sensor. A closed loop temperature control circuit varies the current through the heating element, in accordance with the sensed temperature of the sensor, to maintain the sensor at a temperature approximately equal to that set by a temperature setpoint signal. As the sensor is first placed on a patient, the magnitude of the temperature setpoint signal is increased above its normal value, for a predetermined time, in order to decrease the time delay between the time that the sensor is placed on the patient and the time that the sensor begins to provide usable data.

Abstract: A temperature control system for an electrically heated cutaneous gas sensor. A heating element is provided with heating current by a closed loop temperature control system. The system includes a plurality of temperature monitoring and control circuits which are arranged to turn off a switch that controls the flow of current through the heating element if the temperature of the sensor varies outside of acceptable limits. The system also includes latching circuitry for maintaining the off state of the switch after the occurrence of an out of limits condition, and circuitry for preventing the latching circuitry from being actuated during normal temperature transients.