Heat-sensitive type flow sensor

Abstract

A heat-sensitive type flow sensor which can be manufactured by using discrete parts at low cost in a miniature size with high accuracy and reliability includes a correcting circuitry capable of compensating for a detected current indicating a flow rate of a fluid of concern and outputted from a flow rate detecting circuit. In the heat-sensitive type flow sensor, an arithmetic processing circuit (200) for processing a detection voltage (VM) supplied from a flow rate detecting circuit (100) and indicating the flow rate includes a voltage-to-current conversion circuitry (504) for converting the detection voltage (VM) into a current (I1) and capable of performing gain adjustment, a correcting circuitry (300) for correcting a level of a current signal (I2) outputted from the voltage-to-current conversion circuit (500), and a detection current signal output circuit (600) for outputting the current signal (I01) corrected by the correcting circuitry (300) as a detection output current signal of the heat-sensitive type flow sensor. The correcting circuitry (300) includes diodes implemented as discrete parts which need not exhibit identical characteristic.

Dependencies are inferred from the claim text.