| 摘要 |
PROBLEM TO BE SOLVED: To provide a thermal infrared sensor of high sensitivity, which realizes low noise without broadening of the gate dimension of MOS transistors composing a current source and an integrator and also without voltage multiplication between the gate and the source. SOLUTION: The infrared sensor includes: a detection element the temperature of which varies with incident infrared radiation; a constant current transistor supplying a constant current to the detection element; and a filter circuit connected to the output from the detection element, and detects incident infrared radiation to the detection element from the sensor output outputted from the filter circuit. Since the constant current transistor consisting of two MOS transistors connected parallelly each other the gate of which have a voltage level supplying the constant current and a voltage level keeping accumulation condition below the gate at the respective gates and the rectangular-wave voltage of mutually reversed phases are applied, respectively, the clock frequency of rectangular-wave voltage becomes higher than the cutoff frequency of the filter circuit. COPYRIGHT: (C)2007,JPO&INPIT
|
