1964, Japanese NEO magazine published two enlightening articles: one is "Miniaturizing AC power supply to DC with high frequency technology"; The other is "pulse modulation for miniaturization of power supply". These two articles point out the research direction of miniaturization of switching regulated DC power supply, that is, high frequency and pulse width modulation technology. After nearly 10 years of research and development, good results have been achieved.
1973, Motorola published an article entitled "Initiating a 20kHz Revolution", and since then, the development upsurge of high-frequency switching power supply has been set off in the world. As a switching regulator in switching power supply, DC/DC converter has increased the power density of power supply from 1 ~ 4 W/in3 to 40 ~ 50 W/in3. Firstly, Buck converter is adopted.
By the mid-1980s, buck, boost and buck-boost converters were also applied to switching power supplies. In the mid-1970s, California Institute of Technology developed a new type of switching converter called Cuk converter (named after the inventor S 1obodan Cuk). Cuk converter and Buck-Boost converter are dual and buck-boost converters. It has been gradually applied to switching power supply since the mid-1980s.
1976, p.w., Clarke developed a "primary inductance converter" with transformer (PIC for short), and obtained a patent, which was applied to switching power supply.
1977, Bell Laboratories developed a "single-ended primary inductance converter" with transformer, which is called SEPIC circuit for short. This is a new DC/DC single-ended PWM switching converter, and its dual circuit is called DualSEPIC or Zeta converter.
By 1989, SEPIC and Zeta were also applied to the switching power supply, which increased the number of DC/DC converters used in the switching power supply to six. Up to now, the number of DC/DC converters used in switching power supply has increased to 14 through the evolution and cascade of DC/DC converters. Using these 14 DC/DC converters as the main components of switching power supply, switching power supply with high performance and high power density can be designed, which can be used in different places to meet different performance requirements and uses.