12V Switching Power Supply PCBA Board

Basic Concepts

• Definition: PCBA is the abbreviation of Printed Circuit Board Assembly. The PCBA board of the switching power supply is to install various electronic components on the printed circuit board through welding and other processes to form a complete circuit system with the function of switching power supply.

• Function: Convert, regulate and control the input power supply, output stable DC voltage, and provide suitable power supply for other electronic equipment or circuit modules.

Components

• Printed Circuit Board (PCB): It is the support body of electronic components and the provider of line connection. It is usually made of insulating material with conductive traces and pads on the surface.

• Electronic components: including switching tubes, transformers, capacitors, resistors, inductors, integrated circuits, etc., which are the core components for realizing the function of switching power supply.

• Welding materials: Mainly used to connect electronic components to PCB boards to ensure the electrical connection and mechanical stability of the circuit. Commonly used welding materials include solder paste, solder wire, etc.

Working principle

• Buck principle: When the base of the switch tube is at a high level, the switch tube is saturated and turned on, the inductor stores energy, and the capacitor is charged; when the base of the switch tube is at a low level, the switch tube is turned off, the inductor releases energy, and the capacitor discharges. By adjusting the duty cycle of the base control voltage through the sampling circuit and the feedback circuit, the output voltage can be stabilized and the purpose of voltage reduction can be achieved.

• Boost principle: When the transistors are connected in parallel, the induced electromotive force generated by the inductor is superimposed on the voltage and acts on the load, so that the output voltage is higher than the input voltage. Similarly, the on-off and duty cycle of the switch tube are controlled to achieve boost and voltage regulation.

Performance characteristics

• High efficiency: It works in the off state for part of the time, with low power consumption and less heat. The conversion efficiency is usually high, generally reaching more than 80%, and some high-efficiency switching power supplies can even reach more than 95%.

• Wide input voltage range: It can adapt to a wider input voltage range, such as from tens of volts to hundreds of volts, which can meet the needs of different application scenarios.

• Stable output: Through the feedback control circuit, the fluctuation of the output voltage can be effectively suppressed, the stability of the output voltage can be ensured, and the output voltage ripple factor is low.

• Complete protection functions: It usually has multiple protection functions such as overvoltage protection, overcurrent protection, short circuit protection, overheating protection, etc., which can effectively protect the power supply and load equipment from damage.

Application areas

• Consumer electronics: such as mobile phone chargers, tablet chargers, laptop power adapters, etc.

• Industrial equipment: used for power supply of various industrial automation equipment, instruments and meters, inverters, PLCs and other equipment.

• Communication equipment: Provide stable power supply for communication equipment such as base stations, switches, routers, etc.

• Automotive electronics: such as the power conversion and supply of the engine control unit (ECU), car entertainment system, headlights and other components of the car.