SMPS power unit:

SMPS power unit power supply (also referred to as switching Rectifier SMR) through the MOSFET or IGBT in the high-frequency operation, switching frequency is generally controlled within 50-100 KHz range, ripple factor≤1%, to achieve high efficiency and miniaturization.

SMPS power unit birth process:

1960s large-scale application of the linear regulator DC power supply, because it’s following disadvantages, such as large volume weight, it is difficult to achieve miniaturization, large loss, low efficiency, there are common end between output and input, which difficult to achieve isolation, it can only lower voltage, can’t increase voltage, so it is difficult in the case of the application of output greater than 5A, has begun to be replace by DC SMPS power unit.

In 1964, Japan NEO magazine published two articles instructive:
One article for the “high-frequency technology make AC variable DC power supply miniaturization”;
Another article “pulse modulation for power supply miniaturization.”
These two articles indicates SMPS power unit DC power supply miniaturization research direction, that is one high frequency, the second is the use of pulse width modulation techniques. After nearly 10 years of research, development and achieved good results.

SMPS power unit 20kHZ revolution:

In 1973, Motorola published an article entitled “Trigger from 20kHz of revolution”, all around the world set off a development boom of high-frequency switching power supply and DC/DC converter is used as a switching regulator switching power supply, the power density from 1~4 W/in3 increased to 40~50W/in3. First adopted Buck converter.

By the mid-1980s, Buck, Boost and Buck Boost converter is also applied to SMPS power unit. The mid-1970s, the California Institute of Technology have developed a new switching converter, called Cuk converter (based on the inventor’s name S1obodan Cuk). Cuk converter and Buck-Boost Converter with each other duality, also is a step- down converter. The mid-1980s and then gradually be applied to switching power supply.

In 1976, the United States P. W, Clarke has developed a transformer “primary inductance converter” referred to PIC, patented, and is also applied to the switching power supply.

In 1977, Bell Laboratories on the basis of the PIC, has developed a transformer “single-ended primary inductance converter”, short (with the transformer) SEPIC circuit, this is a new DC/DC single-ended PWM switching converter circuit is called dual DualSEPIC, or Zeta converter.

By 1989, people applied SEPIC and Zeta to SMPS power unit, making switching power supply used in the DC/DC converter, increased to 6 kinds. So far, through DC/DC converter and the cascade evolution, switching power supply used in DC/DC converter has been increased to 14 kinds. Use these 14 kinds of DC/DC converter as a switching power supply, it can be designed in different places, meet different performance requirements and applications, high performance, all kinds of power, high power density switching power supply.