Self-sustained oscillation in an R_H - C or R_H - L circuit containing a hysteresis resistor R_H

When thei - vcurve of a resistor exhibits hysteresis jumps alongiorvaxis, this resistor can be connected to an energy storage elementCorLto form a relaxation oscillator. The criteria of oscillation are derived from a point of view somewhat different from those reported in the literature. It is found that only four different combinations ofRH - CorRH- Lwill support sustained oscillations. Theoretical waveforms and frequencies of oscillations are predicted. Experiments employing an op amp realizedR_Hare conducted and agreement between theoretical predictions and experiments is good. A possible application of the theory to the explanation of biological oscillation across an active membrane is proposed.