Patents Assigned to Integrated Sensor Technologies Inc.
  • Patent number: 5394343
    Abstract: An electronic tire pressure gauge has a tire valve stem receiver, a thin silicon square diaphragm with four diffused resistors configured in a full Wheatstone bridge as a pressure transducer, a voltage controlled oscillator, a comparator, a clock, a microprocessor with program memory, and a display. The comparator compares the stable transducer output for a given pressure with the voltage-controlled oscillator output, to yield a comparator pulse which goes high while the transducer signal is greater than the oscillator signal. The clock provides bus cycles used by the microprocessor for counting the duration of the high comparator pulse. Multiple high comparator pulses are compared, and the longest duration is selected and converted to a pressure value and displayed. Battery power is conserved by a power on/off algorithm.
    Type: Grant
    Filed: April 19, 1993
    Date of Patent: February 28, 1995
    Assignee: Integrated Sensor Technologies Inc.
    Inventor: Kuey Y. Tsao