DC Regulated Power Supply Filter Circuit Overview
Regulated power supply composition and working principle
(1) DC regulated power supply is generally composed of four parts: transformer, rectifier circuit, filter circuit, voltage regulator circuit.
(2) Rectification is the use of diode unidirectional conductivity, the alternating current into pulsating direct current. According to the output waveform, rectification can be divided into half-wave and full-wave rectification. Half-wave rectification requires only a diode, but the output is only half of the sinusoidal waveform, low conversion efficiency. Bridge full-wave rectifier output is two half-wave waveform, the output voltage is doubled, but the number of rectifier diodes is increased to four, the circuit is more complex.
(3) The filter circuit can filter out the AC component in the rectified output and get a relatively smooth DC. The average value of the output voltage is increased by adding capacitor filtering. Capacitive filtering is suitable for load resistance is large, the load current is small occasions. When the capacitor filter can not meet the requirements, can increase the filter, the formation of complex filtering.
(4) voltage regulator circuit can be in the grid voltage fluctuations or load changes, through the automatic adjustment of the regulator device, so that the output voltage is basically stable. Transistor series-type voltage regulator circuit is composed of sampling, reference voltage, comparative amplification, adjustment of several parts, it has a better voltage regulator characteristics, is currently a commonly used circuit. Integrated voltage regulator circuit is more and more widely used due to the advantages of small size, light weight, easy installation and debugging.
(5) The integrated voltage regulator has only three leads, the input, the output and the common terminal, easy to use, better voltage regulation.
