Oscillators--- Neuronal Oscillation

Harmonic oscillator 简谐子！简谐运动！
F=-kx

Relaxation oscillator

A relaxation oscillator is an oscillator in which a capacitor is charged gradually and then discharged rapidly. The capacitor is charged through the resistor, causing the voltage across the capacitor to approach the charging voltage on an exponential curve. In parallel with the capacitor is the threshold device. Such devices don't conduct at all until the voltage across them reaches some threshold (trigger) voltage. They then conduct heavily, quickly discharging the capacitor. When the voltage across the capacitor drops to some lower threshold voltage, the device stops conducting and the capacitor can begin charging again, repeating the cycle. If the threshold element is a neon lamp, the circuit also provides a flash of light with each discharge of the capacitor.