| 摘要 |
PURPOSE:To enlarge the input dynamic range by switching an A/D converting operation when a converted voltage exceeds the voltage range in the A/D converting circuit of the 2<n>R voltage dividing system. CONSTITUTION:In starting the A/D converting operation, the A/D converting operation is performed by connecting an analog switch SW1 to (b) contacts to transmit an input analog voltage Vin to a voltage comparator circuit OP2 as it is. When the resulting voltage exceeds the voltage ranges VH-VL through this converting operation, a CONT2 discriminates it and switches the A/D converting operation to keep the resulting voltage in the operating voltage ranges VH-VL in the voltage comparison circuit OP2. Thus, the input dynamic range is enlarged while keeping the desired A/D converting accuracy. |
