GALVANICALLY ISOLATED MONITORING CIRCUIT

摘要

There is described a system for measuring an environmental parameter such as temperature experienced by a resistive component such as a thermistor (107) in a galvanically isolated circuit, or for measuring the voltage developed by a component. The system comprises a measurement circuit (1) comprising a voltage pulse generator (114). The measurement circuit is inductively coupled to the galvanically isolated circuit by a flyback transformer (101) such that a stable voltage (V104) across a first capacitor (114) in the measurement circuit after many voltage pulses is proportional to a stable voltage (V106) across a second capacitor (106) connected across the component in the galvanically isolated circuit. The stable voltages across the first and second capacitors are adjustable by adjusting a duty cycle of the voltage pulses.