Why are regulated power supplies widely used
There are many classification methods for regulated power supplies. According to the type of output power, there are DC regulated power supplies and AC regulated power supplies; according to the connection mode between the regulated circuit and the load, there are series regulated power supplies and parallel regulated power supplies; There are linear regulated power supply and switching regulated power supply in working state; simple regulated power supply and feedback regulated power supply are divided into circuit types, and so on.
Advantages and disadvantages of switching power supply
advantage:
"Switching regulated power supply" is more efficient and energy-saving than "series-regulated regulated power supply"; it has a strong ability to adapt to changes in mains power; the output voltage can be adjusted in a wide range; one switch tube can easily obtain multiple groups of different voltage levels. Power supply; small size, light weight and many other advantages, and are widely used.
(1) Low power consumption and high efficiency
(2) Small size and light weight
(3) Wide range of voltage regulation
(4) The efficiency of filtering is greatly improved, and the capacity and volume of the filter capacitor are greatly reduced
(5) The circuit form is flexible and diverse
Working principle: After rectification and filtering, the DC voltage is provided by R1 to the base of the regulating tube, so that the regulating tube is turned on. When V1 is turned on, the voltage passes through RP and R2 to make V2 turn on, and then V3 is also turned on. At this time, V1, The emitter and collector voltages of V2 and V3 no longer change (its function is exactly the same as that of the Zener tube). By adjusting RP, a stable output voltage can be obtained, and the ratio of R1, RP, R2 and R3 determines the output voltage value of this circuit.
The difference between linear regulated power supply and switching power supply
The switching regulated power supply realizes voltage conversion and voltage stabilization by converting direct current into high-frequency pulses, and then performing electromagnetic conversion. The linear regulated power supply is directly connected in series with a controllable adjustment element to divide the input DC voltage to realize voltage conversion and voltage stabilization, which is essentially equivalent to connecting a variable resistor in series.
The switching regulator power supply has high efficiency, and it can step up or step down. Linear regulated power supplies can only step down and have low efficiency. Switching regulated power supply will produce high-frequency interference, while linear regulated power supply will have no interference.
