| 摘要 |
PURPOSE:To obtain an oscillator which transduces the difference between two capacitors into a frequency by obtaining a frequency output proportional to the capacity difference from a reset generator. CONSTITUTION:This device consists of a switched capacitor differential integrator 1 which integrates the difference between charges charged in two capacitors Cx and Cy and outputs a voltage proportional to the integrated value, a comparator 3 which compares the output voltage with a reference voltage 6, the reset generator 4 which resets the integrator 1 every time the state of the comparator 3 is inversed, etc., and outputs the frequency proportional to the capacity difference from a terminal 41. The integrator 1 generates the voltage proportional to the difference between both charges in synchronism with clock pulses 2 and outputs the voltage based upon a specific expression in one cycle of a clock frequency. This voltage is integrated (n) times and when the output voltage becomes equal to the voltage Vr of a reference power source 6, the number of times of integration is given as a specific expression. At this time, the generator 4 generates a reset signal, the integrator 4 is reset, and its reset signal is generated at intervals of (n) cycles of the clock period from the generator 2, so that the frequency of the reset signal is proportional to the capacity difference.
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