How to choose the suitable switching power supply chip
Switching power supply chip, in simpler terms, is a integrated block that combines various components used for switching power supply control and protection functions, which are installed together through special processes and then encapsulated. The power supply (start-up) function of the switching power supply chip is to connect a capacitor to ground and a resistor to the positive pole of the input voltage at the VDD pin of the chip. When powered on, the input voltage charges the capacitor through the resistor. When the voltage on the capacitor reaches the start-up voltage threshold of the chip, the chip begins to work. The power supply (maintenance) function of the switching power supply chip is for energy saving. The start-up resistance is relatively large, and the resistor-capacitor combination alone cannot provide the current required to maintain the normal operation of the chip. Therefore, a power supply winding is set on the high-frequency transformer to provide continuous power to the chip. Once the chip starts working, the output voltage of this winding provides a continuous power source for the chip. The gate drive function of the switching power supply chip is that once the chip starts working, the GATE pin drives the switching transistor to be turned on or off, and the various output windings produce voltage outputs.
1. Main Functions and Features
1.1 Feedback control
The control chip is capable of monitoring the output voltage and comparing it with a set reference voltage in order to adjust the conduction time of the switching transistor, thereby stabilizing the output voltage.
1.2 Pulse Width Modulation (PWM)
The control chip utilizes the technique of pulse width modulation to cyclically open and close switch tubes, allowing for precise voltage regulation by adjusting the energy transfer.
1.3 Protection Functions
Switching power supply chips typically come with various protection functions, such as overcurrent protection, overtemperature protection, short-circuit protection, undervoltage lockout, and overvoltage protection, to ensure the safety of both the power supply and the load.
1.4 Soft start
The control chip enables the soft start function, gradually increasing the output voltage and reducing the current surge during startup.
1.5 Dynamic Response
The switch power control chip possesses a rapid dynamic response capability, enabling it to adapt to changes in load and transient demands.
1.6 Electrical Isolation
In certain applications, control chips may possess the capability of electrical isolation to enhance system security.
1.7 External Component Configuration
Switching power supply chips typically require the use of external components (such as switching transistors, inductors, capacitors, etc.) to achieve a complete switching power supply system.
2. Common Categories
Switching power supply chips can be classified based on their different characteristics and functions. Here are some common classifications of switching power supply chipchips:
2.1 PWM Controller:
These types of control chips are focused on generating PWM signals to control the on and off states of switching transistors. They are typically used in conjunction with external components such as switching transistors, inductors, and capacitors to build complete switch-mode power supplies. PWM controllers are commonly employed in high-power switch-mode power supplies.
2.2 Buck controller
A buck controller is designed to reduce the input voltage to a desired lower output voltage. It is particularly suitable for applications that require an output voltage lower than the input voltage, such as mobile devices and communication equipment.
2.3 Boost Controller
The boost controller is designed to increase the input voltage to the desired higher output voltage, commonly used in applications that require high-voltage driving, such as LCD backlighting and high-voltage drivers.
2.4 Flyback Controller
The flyback controller is utilized to achieve galvanic isolation in power supply designs, typically found in devices such as televisions and computer monitors.
2.5 Half-Bridge Controller
The half-bridge controller is employed to drive the switch-mode power supply with a half-bridge topology, suitable for high-power applications such as industrial power supplies and electric vehicle chargers.
2.6 Multi-phase controller
A multi-phase controller combines multiple switched-mode power supplies in parallel to enhance efficiency and power density. They are commonly employed in high-power applications, such as server power supplies and industrial power systems.
2.7 Synchronous rectification controller
The synchronous rectification controller is utilized to optimize energy transfer efficiency and is commonly employed in conjunction with synchronous rectification MOSFETs.
2.8 Power Management IC (PMIC)
The Power Management IC is an integrated circuit that incorporates a variety of power management functions, including switch-mode power control, LDO voltage regulators, and battery charging/discharging management. They are commonly employed in mobile devices and portable electronic products.
2.9 led driver controller
A device specifically designed to control the switch-mode power supply of LED lighting driver circuits, suitable for applications such as LED strips and backlighting.
2.10 Automotive Power Controller
Designed specifically for the unique requirements of automotive electronic systems, the switch power controller possesses characteristics that enable it to adapt to the voltage range and environment of automobiles.
The aforementioned is a list of some common classifications of Switching power supply chips. In reality, there are even more specialized and feature-rich switch power controllers available. When selecting the appropriate control chip, it is necessary to evaluate and choose based on specific application requirements and technical parameters.
3. Application Fields
Switching power supply chips are widely used in various electronic devices and systems to provide efficient and stable power conversion functionality. Here are some common application areas for Switching power supply chips:
3.1 Communication Equipment
This encompasses mobile phones, base stations, routers, switches, and other communication devices, all of which require efficient and stable power supply to support their communication functions.
3.2 Computers and servers
Control chips are used to provide stable power supply for computers and servers, supporting various computing and data processing tasks.
3.3 Consumer Electronics
Consumer electronic products such as televisions, sound systems, and household appliances require a stable power supply to ensure their proper functioning.
3.4 Industrial automation
It is used for industrial control, automation equipment, and robots to ensure stable power supply for industrial equipment.
3.5 Medical Equipment
Medical imaging devices, monitoring equipment, medical instruments, and other devices require power sources with high reliability and stability.
3.6Power equipment
Used in power conversion and distribution systems, such as inverters, variable frequency drives, etc.
3.7 Aerospace
In the field of aerospace, switch-mode power controller chips are utilized in satellites, aircraft, and space probes, among other applications.Switching power supply control chips are commonly used in conjunction with switching devices such as MOSFETs and other external components to build complete switching power supply systems. These control chips can be employed in a variety of applications, including communication equipment, computers, consumer electronics, industrial control, and medical devices. They provide efficient and stable power solutions for electronic devices.
