| 摘要 |
<p>PURPOSE:To measure the current speed with high linearity over a wide current speed range while suppressing the fluctuation in the output signal caused by the ambient temperature or the aging of elements. CONSTITUTION:The thermal current sensor comprises a trench 6 made in a semiconductor substrate 7, an electric insulation film 3 bridging the trench 6, a heating element 1 and a temperature measuring element 2 therefor disposed on the bridge, and a fluid temperature measuring element 4 disposed on a part of the insulation film 3. The heating element 1 is driven such that the elements 2 and 4 exhibit different temperature difference and a current speed signal is obtained by subtracting the potential difference V2 across the heating element 1 at the time of driving with a low temperature difference from the potential difference V1 across the heating element 1 at the time of driving with high temperature difference.</p> |
