Switching Power Supply, also called Switching Power Supply, Switching converter, is a kind of high frequency electric energy conversion device.Its function is to a voltage level, through the different forms of architecture into the voltage or current client demands.
Compared with the traditional linear power supply, switching power supply has the advantage of high efficiency, the efficiency can be as simple as the input power and the ratio of output power), combined with the switching transistor in switch state, small loss, low fever, do not need size/weight very big radiator, so a smaller volume, lighter in weight.But when switching power supply work, because the frequency is higher, can cause interference to the power grid and the surrounding equipment, therefore, must properly deal with this problem.
Advantage of linear power supply structure is relatively simple, relatively high reliability of current ripple rate can easily achieve low, maintenance more convenient also.
In fact, modern circuit, switching power supply and linear power supply circuit, in most cases, is a combination - the use of switching power supply, carries on the preliminary transformation to ripple, the accuracy is not high circuit use;At the same time, the use of A low dropout linear power supply circuit (LDO) to obtain precision, low voltage ripple (noise) for such as operational amplifier (OP-AMP), AD Converter is used.