In recent years, driven by the rapid growth of downstream electronic product manufacturing, China's power management chip market has maintained steady growth. According to SEMI data, the market size of China's power management chip reached 73.6 billion yuan in 2019, a year-on-year increase of 8%. It reached 79 billion yuan in 2020, with a compound annual growth rate of 7% from 2015 to 2020. With broad downstream application areas and a thriving related application terminal market, strong downstream demand will be a powerful driving force for the continued growth of the entire power management chip industry in the future.
Power management ICs (PMICs) are integrated circuits used to manage power consumption. They help reduce power consumption, improve system reliability and stability, and are widely used in various electronic devices and systems. In modern electronic products, PMICs have become one of the essential chips.
The selection of power management IC chips is mainly based on the following parameters:
Power consumption: Power consumption is an important parameter of power management IC chips, reflecting the chip's energy consumption. Power consumption of power management IC chips is generally divided into two types: static power consumption and dynamic power consumption. Static power consumption refers to the power consumption in the chip's standby state, while dynamic power consumption refers to the power consumption in the chip's operating state.
Conversion efficiency: Conversion efficiency is another important parameter of power management IC chips, reflecting how efficiently the chip converts input electrical energy into output electrical energy. The conversion efficiency of power management IC chips is generally divided into three types: input efficiency, output efficiency, and application efficiency.
Voltage regulation accuracy: Voltage regulation accuracy refers to the precision with which a power management IC chip regulates the input voltage. The higher the voltage regulation accuracy, the more stable the chip's output voltage.
Current control accuracy: Current control accuracy refers to the precision with which a power management IC chip controls the output current. The higher the current control accuracy, the more stable the chip's output current.
Temperature control accuracy: Temperature control accuracy refers to the precision with which the power management IC chip controls the chip temperature. The higher the temperature control accuracy, the more stable the chip temperature.
Response speed: Response speed refers to how quickly a power management IC chip responds to an input signal. The faster the response speed, the more precise the chip's control.
Reliability: Reliability refers to the performance of a power management IC chip under prolonged use and frequent switching. Higher reliability means a longer chip lifespan.
Competitive Landscape of Power Management Chips
After understanding the selection parameters, it is also important to know the manufacturers of power management chips.
Currently, the Chinese power management chip market is still dominated by European and American companies, with Chinese manufacturers holding a relatively low market share. According to Chipown Microelectronics' prospectus, as of May 2020, European and American companies held over 80% of the market share in China, and Chinese companies are still unable to compete with European and American manufacturers such as TI, ADI, and Infineon in terms of production and sales scale. The top five Chinese manufacturers in terms of market share are Chipown Microelectronics, Silan Microelectronics, Shanghai Belling, Fuman Electronics, SG Micro, and Chipown Microelectronics, with Chipown Microelectronics holding the highest market share at 1.13%. In terms of product categories, domestic manufacturers all have around 1,000 product categories, with SG Microelectronics slightly leading other companies in power management chips with over 1,000 products. The simultaneous upgrading of sub-product technologies and application areas, along with the diverse product range, has resulted in low industry concentration. The more industry application areas a company has and the more product categories it has, the stronger its competitiveness. For example, Texas Instruments (15%) is the leading manufacturer with the highest market share in power management chips. According to the prospectus of Chipown Microelectronics, it has more than 100,000 product categories, which is a huge lead over Chinese manufacturers. Chinese power management chip companies have relatively weak cross-product line and cross-industry capabilities, so their product categories and market share are relatively small compared with European and American companies.
What is a power supply chip? What is its function? What factors should be considered when selecting a power supply chip? What is the input voltage linearity regulation rate, and how does the linear change in input voltage affect the output voltage? Let's first understand a few conceptual questions:
1. Output voltage load regulation: The relative change in output voltage when the load current changes.
2. Output voltage accuracy: The error range of the device's output voltage.
3. Load transient response: The fluctuation of output voltage when the load current changes rapidly from a small value to the maximum current.
4. Should the power supply chip be a DC/DC converter or an LDO?
This depends on your application. For example, if it's for boosting, you can only use a DC/DC converter because an LDO is a dropout converter and cannot boost.
Let's also look at their main characteristics:
DC/DC: High efficiency, high noise;
LDO: Low noise, low quiescent current;
Therefore, if the voltage drop is relatively large, choose DC/DC converter because of its high efficiency, while LDO converters will lose a large portion of their efficiency due to the large voltage drop.
If the voltage drop is relatively small, choose an LDO because it has low noise, clean power supply, simple peripheral circuitry, and low cost.
LDO stands for Low Dropout Regulator, which is a power converter in contrast to traditional linear regulators. Traditional linear regulators, such as the 78xx series chips, require the input voltage to be 2V-3V higher than the output voltage to function properly. However, in some cases, this condition is clearly too stringent. For example, in a 5V to 3.3V conversion, the input-output voltage difference is only 1.7V, which obviously does not meet the requirements. LDO-type power conversion chips were developed to address these situations.
LDO (Linear Diode) step-down chips: Their principle is similar to a resistor divider to achieve voltage reduction. This results in significant energy loss, as the reduced voltage is converted into heat. The greater the voltage drop and the larger the load current, the more pronounced the chip's heat generation. These chips are typically packaged in a larger size for better heat dissipation.
LDO linear step-down chips such as the 2596 and L78 series.
DC/DC buck converter chips: These chips exhibit low energy loss and minimal heat generation during the buck conversion process. They also feature a small package and enable PWM digital control.
DC/DC step-down chips such as: TPS5430/31, TPS75003, MAX1599/61, TPS61040/41
LDO stands for low-dropout regulator, which is a type of linear regulator in contrast to traditional linear regulators. Traditional linear regulators, such as the 78xx series chips, require the input voltage to be 2V to 3V higher than the output voltage; otherwise, they will not function properly.
However, in some cases, such conditions are clearly too stringent. For example, in a 5V to 3.3V conversion, the input-output voltage difference is only 1.7V, which obviously does not meet the requirements. LDO (Low Voltage Regulator) chips were developed to address these situations. Many companies manufacture LDO chips, including ALPHA, Linear Technology (LT), Micrel, National Semiconductor, and TI.
Power management chips are one of the core components in electronic products responsible for power management and protection. Selecting a suitable power management chip can improve system efficiency, extend battery life, and prevent system damage.
1. Methods for selecting power management chips
1.1 Determine power requirements: First, it is necessary to determine the required voltage and current values of the power supply in order to select a suitable power management chip.
1.2 Chip power consumption: Consider the power consumption of the chip to avoid selecting chips that may cause problems such as overheating, short lifespan and poor stability.
1.3 Package Type: The package type is crucial to the operating environment of the power management chip. Common package types include QFN, WLCSP, and BGA, and the appropriate type should be selected based on the specific requirements.
2. Causes and solutions for power chip overheating
2.1 Causes: The main reasons for power supply chips overheating are excessive power consumption, poor heat dissipation, and excessively high ambient temperature. Excessive temperature can lead to decreased performance or even damage to the power supply chip.
2.2 Solutions: Heat dissipation can be improved by adopting heat dissipation design or adding heat sinks. Power consumption can also be reduced by adjusting parameters such as input voltage or frequency.
As an indispensable part of electronic systems, power modules are extremely common and also one of the most demanding areas for hardware engineers to master. A power module is a subsystem in an electronic system that performs functions such as power conversion, distribution, control, and monitoring. The power consumption, performance, cost, and size of the entire electronic system are directly related to the design of the power module. Modern large-scale electronic systems are developing towards high integration, high speed, high gain, and high reliability. Even minor disturbances in the power supply can affect the performance of electronic devices, necessitating the design of power modules with low noise and strong ripple immunity. In portable devices, battery power is increasingly used, placing high demands on battery life, which typically corresponds to the extreme requirements of high efficiency, high reliability, and low quiescent current in their power modules.
In summary, power module design is fundamental to the performance of electronic systems. Only after a well-designed power module can a system pursue performance and reliably implement all its functions. A crucial aspect of power module design is selecting the appropriate chip and technical solution. Typically, based on the characteristics of each branch in the power module, the input and output voltage differences are determined. Then, considering application requirements and constraints such as efficiency, heat dissipation limitations, noise requirements, system complexity, and cost, the most suitable power chip can be selected. Finally, the selected power chip is used to implement the corresponding power conversion and distribution functions.
