| 摘要 |
PURPOSE:To provide an accurate thermometer of a simple constitution by displaying temperautures with the beat frequencies of reference signals for time and thermometer. CONSTITUTION:Reference signal for thermometer from terminal 8b and inverted reference signal for delay thermometer through inverter I6 are applied via NAND gate G1, inverter I7 to NAND gates G2, G3. On the other hand, the inverted reference signal for time via inverter I3, the reinverted reference signal for time and the non-inverted reference signal for time via inverters I4, I5 and the inverted delay time reference signal via inverter I4 are applied to gates G2, G3 respectively. Hence, the gates G2, G3 generate low level outputs when the fall of the reference signal for time and the rise of the reference signal for thermometer overlap and when the rises of both reference signals overlap. This causes the signals corresponding to the beat periods of both reference signals proportional to temperatures to be generated through R-S type FFs G4, G5, thus temperatures may be accurately displayed without using thermistors having accuracy distribution differences with the simple constitution of not requiring A/D conversion. |
