The basic concept of metal push button switch
Metal push button switch is a kind of power supply that uses modern power electronic technology to control the timing ratio of switch tube registration and turn off to maintain a stable output voltage. Metal push button switches are usually composed of pulse width modulation control ICs and MOSFETs. Comparing the metal push button switch
and the linear power supply, the cost of both increases with the increase of output power, but the increase rate of the two is different. The linear power supply cost is higher than the metal button switch at a certain output power point, which is called the cost turning point. With the development and innovation of power electronics technology, the metal button switch technology is also constantly innovating. This cost turning point is increasingly moving to the low-output power end, which provides a wide development space for metal button switches.
The high frequency of metal button switches is the direction of its development. The high frequency has made the metal button switch smaller, and made the metal button switch into a wider range of use, especially in the field of high and new skills, and promoted the miniaturization of high-tech products. Facilitate and portable. The deployment and use of other metal button switches have important implications in terms of energy saving, capital saving and environmental maintenance. The power electronic equipment used in metal push button switches are mainly diodes, IGBTs and MOSFETs. SCR is used in a small number of metal button switch input rectifier circuits and soft-start circuits. GTR is difficult to drive and has a low switching frequency. It is gradually replaced by IGBTs and MOSFETs.
Three conditional folding
1. Switch: The power electronic equipment is operated in the switch state rather than the linear state
2. High frequency: power electronic equipment operates at high frequency instead of low frequency close to power frequency
3. DC: The metal button switch outputs DC instead of communication
Classification of metal push button switches
Everyone in the field of metal button switch skills is to develop related power electronic equipment and switch frequency conversion skills. The two promote each other to promote the metal button switch to be light, small, thin, low noise, and high with an increase rate exceeding two digits every year. Unfold in a reliable and anti-disturbance direction. Metal button switches can be divided into two categories: AC/DC and DC/DC. DC/DC converters have been modularized, and planning skills and production skills have been experienced and standardized at home and abroad, and have been recognized by users. However, the modularity of AC/DC, due to its own characteristics, makes it encounter more messy skills and skills production problems in the process of modularization. The structure and characteristics of the two types of metal button switches are discussed below.
Metal push button switches
have more interference than linear power supplies. Electrical equipment that is sensitive to common mode interference should be grounded and shielded. According to EMC constraints such as ICE1000, EN61000, and FCC, metal push button switches adopt EMC electromagnetic compatibility methods. Therefore, the metal button switch should usually be equipped with EMC electromagnetic compatibility filter.
Metal button switches must have maintenance functions such as overcurrent, overheating, and short circuit in the planning. Therefore, the metal button switch module with complete maintenance functions should be preferred when planning, and the technical parameters of the maintenance circuit should be consistent with the operating characteristics of the electrical equipment. Match to prevent damage to electrical equipment or metal button switches.
The expansion direction of the metal button switch is high frequency, high reliability, low consumption, low noise, anti-interference and modularization. Because the key technology of light, small and thin metal button switches is high frequency, major foreign metal button switch manufacturers are committed to the simultaneous development of new and highly intelligent element equipment, especially to improve the loss of secondary rectifier equipment, and Increased technological innovation in power ferrite materials to improve the ability to achieve high magnetic functions at high frequencies and large magnetic flux densities, and miniaturization of capacitors is also a key skill. The use of SMT technology has made the metal push button switch have made great progress. The components are arranged on both sides of the circuit board to ensure that the metal push button switch
is light, small and thin.
The high frequency of metal button switches will inevitably innovate the traditional PWM switch technology. The completion of the soft switching skills of ZVS and ZCS has become the main stream technology of metal button switches, and has greatly improved the operating efficiency of metal button switches. Regarding the goal of high reliability, American metal push button switch
manufacturers have reduced the stress of the equipment by reducing the operating current and lowering the junction temperature, so that the reliability of the product has been greatly improved.
Modularity is the overall trend of metal button switch deployment. Modular power supplies can be selected to form a distributed power system, can be planned into an N+1 redundant power supply system, and complete the capacity expansion of the parallel method. For the defect of large operating noise of metal push button switches, if you seek to increase the frequency alone, the noise will also increase. However, using some resonant conversion circuit technology can theoretically complete the high frequency and reduce the noise.