| 摘要 |
PURPOSE:To provide a low-cost, high-performance electronic thermometer by reducing the dimensions of various circuits. CONSTITUTION:An electronic thermometer has a resistance-value-to-frequency conversion circuit 1 which selectively produces reference pulse signals having frequencies matching the resistance value of a reference resistance 102 and detection pulse signals having frequencies matching the resistance value of a thermistor 101; a divider circuit which, after counting the reference pulse signals before a count aborting value is reached, is reset to count the detection pulse signals over a time equal to the counting time of the reference pulse signals; a divider circuit 5 for determining counting time for every temperature measuring process by counting clocks from an oscillating circuit 4 before the count aborting value is reached; and an initial logarithm adjusting circuit 3 serving as an aborting value setting means for setting the count aborting value to meet resistance variation correction data. The initial logarithm adjusting circuit 3 consists of an initial value setting circuit 61 which converts the logarithm value of the LO outputs of the AND output of the divider circuit 2 based on the resistance variation correction data and a gate setting output circuit 60. |
