What is the difference between switching power supply and regulated power supply?
There are many types of regulated power supplies, and series regulated power supplies are composed of power transformers, rectifier components, filtering capacitors, regulating components (such as regulating tubes or tri voltage regulators), reference voltages, sampling networks, comparative amplifiers, and overload or short-circuit protection. Due to the fact that the series stabilized power supply belongs to a linear stabilized circuit, and the regulating tube is convenient for stabilizing the voltage. Its disadvantages are high power consumption, low efficiency, and allowing for a small range of grid fluctuations. Generally, series stabilized power supplies allow a fluctuation range of (220 ± 22) V. In order to reduce power consumption and improve efficiency, switch mode stabilized power supplies are introduced.
1. Switching power supply directly rectifies, filters and adjusts the voltage of the power grid, and then stabilizes it with a switching regulator. So no transformer is needed.
2. Switching power supplies generally use power semiconductor devices as switches, and adjust the output voltage by controlling the duty cycle of the switches. Taking the power transistor (GTR) as an example, when the switching transistor saturates and conducts, the voltage drop across the collector and emitter is close to zero. When the switching transistor is turned off, the collector current is zero, resulting in low power consumption and high efficiency. The efficiency can reach up to 70% to 95%. And with low power consumption, the heat sink also decreases accordingly.
3. The operating frequency of the switch is in the tens of kilohertz range, and the capacity values of the filtering capacitors and inductors used are relatively small. Therefore, switch mode power supplies have the characteristics of light weight and small size.
4. Due to low power consumption and low internal temperature rise, the stability and reliability of the entire machine are improved.
There are two types of power supplies: switching power supplies and regulated power supplies. These two types of power supplies have differences, but they also have similarities.
Switching power supply is a widely promoted regulated power supply in modern times, which has the characteristics of high efficiency, wide voltage range, and stable output voltage. It is now widely used.
For example, ATX power supplies for computers, laptop power adapters, printer power supplies, mobile phone chargers, and so on. A regulated power supply maintains a fixed output voltage when the load power changes. Switching power supply is also a regulated power supply, but a regulated power supply cannot be directly referred to as a switching power supply.
A regulated power supply is a power supply that uses electronic circuits to output voltage to achieve stability. There are series regulated power supplies, parallel regulated power supplies, and switch regulated power supplies.
Ordinary series stabilized power supplies are equipped with power transformers, which have the advantages of stable output voltage and small ripple, but have a small voltage range and low efficiency.
