Overview of Filter Circuit for DC Stabilized Power Supply
Composition and working principle of a regulated power supply
(1) DC regulated power supply generally consists of four parts: transformer, rectifier circuit, filter circuit, and regulated circuit.
(2) Rectification utilizes the unidirectional conductivity of a diode to convert 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 only requires one diode, but the output is only half of the sine wave, resulting in low conversion efficiency. The output of bridge full wave rectification is two and a half cycle waveforms, and the output voltage has doubled, but the number of rectifier diodes has increased to four, making the circuit more complex.
(3) The filtering circuit can filter out the AC component in the rectifier output and obtain a relatively smooth DC current. The average output voltage increases after adding capacitor filtering. Capacitive filtering is suitable for applications with high load resistance and low load current. When capacitive filtering cannot meet the requirements, * * filtering can be added to form a complex filtering.
(4) The voltage stabilizing circuit can stabilize the output voltage by automatically adjusting the voltage stabilizing device during voltage fluctuations or load changes in the power grid. The transistor series voltage stabilizing circuit is composed of sampling, reference voltage, comparative amplification, and adjustment parts. It has good voltage stabilizing characteristics and is currently widely used as a circuit. Integrated voltage stabilizing circuits are increasingly widely used due to their advantages such as small size, light weight, and convenient installation and debugging.
(5) The integrated voltage regulator only has three output terminals: input terminal, output terminal, and common terminal, which is convenient to use and has good voltage stability.
