Parasitic capacity measurement method for FETs - has transistors periodically switched by suitable voltage and known capacity parallelly charged and discharged for comparison

摘要

The method described has been designed to measure the parasitic capacities between the gate and the source electrodes on one side and the gate and the drain electrodes on the other and these depend on the intrinsic voltage of the metal oxide (MOS) field-effect transistors in question.$ The transistor is periodically switched, by a suitable voltage, between a switched-on and a switched-off state and a reference capacity of known value in parallel with it is charged and discharged. During this process the voltages on the source and the drain electrodes and also on a second terminal of the transistors are maintained at a constant value. The currents through the electrodes and the reference capacity are actually measured and from these the capacities can be obained.$ ADVANTAGE - Improvement in accuracy.