Impedance characteristics of switching power supply module
2022-05-20

The impedance characteristic of switching power supply module refers to that the power circuit composed of internal resistors, capacitors and inductors has blocking effect on AC current. The characteristic impedance of resistor is itself, and the resistance of capacitor and inductor to AC current is called reactance.


Capacitors in the power circuit to block AC current is called capacitive reactance. The larger the AC frequency is, the smaller the capacitive reactance is, which has the effect of isolating direct AC. Inductors block AC current in the power circuit, which is called inductive reactance. The greater the AC frequency, the greater the inductive reactance. It has the effect of direct and AC isolation of AC current, and can carry out filters.


A large resistance in the power module will be detrimental to the work of the load regulator circuit. All changes in the relatively serious load current will cause fluctuations in the output of the control module. The harm of fluctuations to the detection is the same as that of single pulse and noise to the detection results.


When the line voltage or load current flow changes, the output working voltage of the DC power module will fluctuate. The level of the regulator is determined by the main parameters of the regulator circuit, the volume of the filter capacitor and the speed of kinetic energy release. The stable size is the percentage or transition value of the output working voltage at full load or full load.


The transient does not respond or the repair time is usually 12% when the load changes. The output offset is calibrated by the millivolts of the common output offset Valley working voltage, and the repair time is indicated by the common millivolts of the output repair to the standard value.


The size of the transient non response and repair time of the power module indicates that when the output load changes suddenly, the voltage stabilizing circuit recovers the working voltage. The size of the working capacity is usually calibrated by the offset value of the output when the load suddenly changes greatly or the time commonly used to repair the output to the original value.