Oscillator arrangement for measuring capacitance change, has reference oscillator oscillating to develop frequency and pulse width modulated signal, and ESD-prevention circuit with small self-capacitance against electrical zero point switch

摘要

The arrangement has a reference oscillator with a fixed time constant and high impedance signal input. The oscillator is controlled in such a manner that it oscillates by a measuring oscillator to develop a frequency and pulse width modulated signal at the arrangement output. An ESD-prevention circuit with small self-capacitance is arranged against an electrical zero point switch in a direction of measuring capacitor.