Buck PWM DC-DC Power Management IC Design

Memory chip

In recent years, with the rapid expansion of the portable electronic product market, the demand for power management chips has also increased. The portable technology requires the power management chip to have low power consumption and small size. Pulse width modulation, as a voltage conversion method, is widely used because of its high conversion efficiency and easy implementation. This paper mainly studies the design of current-mode pulse width modulation DC-DC controller chip.

This paper analyzes the working principle and circuit structure of the current-type buck pulse width modulation control chip, and designs the main functional blocks inside the chip, including reference, op amp, oscillator, comparator, logic drive and protection circuit. The transistor-level circuit diagrams are given respectively. Each function block has been verified by Hspice software and the simulation results are given, thus completing the overall circuit design. The simulation results show that the chip meets the design requirements under different working conditions, and the overall circuit structure is simple, the output voltage precision is high, the power consumption is low, and the area is small. Finally, the paper also gives the layout design.

With the widespread use of various home appliances and portable handheld electronic devices, power management chips have entered almost every electronic product. At present, China is producing more than 10 million air conditioners, washing machines, refrigerators, microwave ovens, flat-panel TVs, hundreds of millions of mobile phones, personal computers, digital cameras, DV, MP3 music players, etc., all of which require power management chips to drive. And management. Since the power management chip is matched with the entire semiconductor, its demand is huge. This has made the status of power management ICs more and more important, and has become the main battlefield for semiconductor manufacturers to compete. In addition, portable products have always been one of the main application areas of power management ICs. With the increasing use of semiconductor terminal products, consumers are increasingly demanding functions, performance, size and cost, and power demand and battery life are long. Becoming a must, these make the power management market vibrant, but also put more complex and strict requirements on power management technology [l. l, thus speeding up the power management IC structure upgrade process. In addition, with the increasing trend of “electronics” in automobiles, automotive electronics products have received more and more attention, which undoubtedly provides an opportunity for the future development of the power management IC market.

Of course, not only is the demand driven, the IC industry continues to develop in accordance with Moore's Law to make the semiconductor manufacturing process more sophisticated, improper handling of power problems will become the bottleneck of IC development. Therefore, the development of power supply is gradually transferring the pressure to the power management IC design. High-frequency switching power supply, low power consumption is the direction of its development, high frequency makes the switching power supply miniaturized, and the switching power supply enters a wider range of applications, especially in high-tech applications, promoting high-tech products. Miniaturized and lightweight. In addition, the development and application of switching power supplies are of great significance in terms of energy conservation, resource conservation and environmental protection.

The development of switching power supply technology is mainly reflected in two aspects: First, the design and process realization of related power electronic devices, and first, the improvement of switching frequency. The mutual promotion promotes the development of switching power supplies in the direction of light, small, thin, low noise, high reliability and anti-interference with an annual growth rate of more than two digits. Switching power supply can be divided into AC. DC and DC. DC two major categories. Among them, DC. The DC converter has been modularized, and the design technology and production process have been matured and standardized at home and abroad, and are suitable for battery-powered portable systems. According to the evolution of the global semiconductor market in recent years, we can find that the Asian market has risen very rapidly and now ranks first in the world. In general, the mainland and Taiwan markets account for at least two-thirds of the Asian market. Therefore, in recent years, foreign semiconductor giants have invested in factories in China, established IC R&D centers, and cooperated with enterprises and established joint laboratories with some famous universities, all of which will rapidly promote the development of China's semiconductor industry. Therefore, the semiconductor market on both sides of the strait will soon lead the world. The same is true for power management semiconductors. Its share in the entire semiconductor market is gradually increasing, and its share in the world market is further increasing. Therefore, China's power management ICs are facing greater opportunities and heavier burdens.

Bucky current mode PWM switching power supply loop control block diagram

Bucky current mode PWM switching power supply block diagram

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