If the SMPS has an AC input, then the first stage is to convert the input to DC. This is called rectification. An SMPS with a DC input does not require this stage.
The inverter stage converts DC, whether directly from the input or from the rectifier stage described above, to AC by running it through a power oscillator, whose output transformer is very small with few windings at a frequency of tens or hundreds of kilohertz. The switching is implemented as a multistage (to achieve high gain) MOSFET amplifier. MOSFETs are a type of transistor with a low on-resistance and a high current-handling capacity.
If the output is required to be isolated from the input, as is usually the case in mains power supplies, the inverted AC is used to drive the primary winding of a high-frequency transformer. This converts the voltage up or down to the required output level on its secondary winding. The output transformer in the block diagram serves this purpose. If a DC output is required, the AC output from the transformer is rectified. For output voltages above ten volts or so, ordinary silicon diodes are commonly used. The rectified output is then smoothed by a filter consisting of inductors and capacitors. For higher switching frequencies, components with lower capacitance and inductance are needed.
For, non-isolated power supplies contain an inductor instead of a transformer. This type includes:-
1) boost converters,
2) buck converters,
3) buck-boost converters.
These belong to the simplest class of single input, single output converters which use one inductor and one active switch A feedback control loop is employed to regulate the output voltage by varying the duty cycle to compensate for variations in input voltage. For an optimized power supply Custom Design is mandatory thus having different Voltage and Current ratings. Akshat Autoline Pvt. Limited Specializes in this area by helping industries reduce their R&D costs, add various features keeping in mind the technical specifiaction and world class quality standards.
