| 摘要 |
PURPOSE:To improve accuracy by reading a battery voltage value and correcting the output of a pressure sensor which operates on the battery voltage as a voltage source. CONSTITUTION:A control unit is constituted of a CPU contg. a read-only memory element ROM, a random access memory element RAM, an input/output interface I/O, an analog-digital converter A/D and resistors R1, R2 which divide battery voltage. The voltage dividing signal for the battery voltage and the output signal of a pressure sensor are connected to an A/D input terminal. The battery voltage and pressure data at the present point of time are read and are stored in the element RAM and the pressure data corrected by using a correcion factor is stored in the another address of the element RAM. The corrected pressure is used as control data. The output error owing to the fluctuation in the battery voltage is thus eliminated. |
