Non-linear analysis of an active peak detector
Gerald T. Volpe · 1985
The transient response of an active peak detector is analyzed assuming appropriate non-linearites for the drive amplifier and coupling diode, as well as dynamics for the capacitive load and the amplifier's gain - bandwidth. A piecewise linear model development is compared to the quasi-exact solution of the describing non-linear differential equation. The results show that the piecewise linear model predicts an underdamped clamped response to a step, whereas the quasi-exact response shows monotonic behavior. The discrepancy is explained on the basis of a gradual change in the coupling diode's impedance as peak detection occurs in reality versus a ficticious abrupt change in the diode impedance as assumed for the linear piecewise model.