Working principle of switching power supply chip
Working principle of switching power supply chip
Switching power supply is a new type of power supply system, and its working principle is to realize the conversion of electric energy and energy based on the continuous opening and closing of switching devices, and to realize the process of obtaining the required stable voltage or current from the input power supply.
Switching power supply chip is the core component of switching power supply, which can select the relevant working mode according to the input voltage range and output voltage requirements, and realize the power conversion between input power supply and output load through open-close switching devices.
The main working modes of switching power supply chip include offline mode and open-closed loop mode, which are obviously different in function, fluctuation and response.
1. Offline mode
Offline mode is usually suitable for low-power and low-voltage applications, which is characterized by stable output voltage, no need for electrical isolation between applications, and relatively simple maintenance.
Off-line mode switching power supply chip has the following main features:
(1) Wide input voltage range: Due to the need to support all voltage values ranging from deformed peak voltage to peak voltage, the input voltage range is usually much wider than that of ordinary transformers.
(2) High-capacitance load: Due to the need to support large-capacity loads, the input capacitance is usually very large.
(3) Low noise: For applications requiring low noise, the switching power supply chip needs to be optimized and adjusted.
(4) High efficiency: In order to ensure the output efficiency of switching power supply, high efficiency runoff mode should be adopted in the design.
(5) Low cost: In order to improve the cost competitiveness of products, it is often necessary to adopt cheap devices and design to save costs.
Off-line mode switching power supply chip is essentially an electronic circuit that realizes automatic switching between two different working states. When the power supply is turned on, the chip is mainly responsible for starting and supplying the power supply, and when the power supply is turned off, the chip is mainly responsible for maintaining the stability of the output voltage.
2. Open and closed loop mode
Open-closed loop mode is an advanced power switch mode, and its control principle is based on a specific feedback loop, which can ensure stable output voltage and tightness feedback when the output current load types and changes.
The open-closed mode switching power supply chip has the following main characteristics:
(1) Faster response: The open-closed loop mode can quickly adjust the output voltage and current, making the response speed of switching power supply faster. It is mainly used for ships with high-speed data signal replacement and initial electronic equipment fragmentation.
(2) Strong ability to cope with changes: the open-closed loop mode can automatically adjust the output voltage and current, and adapt to the changes of load current range while maintaining the quality of output voltage.
(3) Wide voltage range: wide input voltage range is supported, and the output voltage range is not affected by power supply changes, so that the application range of the product is wider.
(4) saving power consumption: supporting the production of more energy-saving products, thus reducing the design cost of a series of operations.
Open-closed-loop switching power supply chip uses AC voltage and DC power supply with specific feedback loop to realize power regulation and stabilize energy adaptation, so that electronic equipment can operate stably and reliably under normal working principle, thus ensuring the stability and stability of equipment.
