What is buck converter

What is buck converter?

The buck converter is a complete circuit which do step down voltage from input DC to DC, basically it can give fixed voltage, such as if its input is 20v or 15v and its output has fixed at 12v, if input voltage will increase, so its output voltage will not change, the output remain fixed at 12v, this thing makes to it special and useful.

Where is used of buck converter?

The buck converter typically used in computer, laptop, mobile, circuits, even Laptop and Mobile changers, and also SMPS works by buck converter, the SMPS basically a power supply which used in computer.

The Buck Converter is utilized in SMPS circuits where the DC yield voltage should be lower than the DC input voltage. The DC info can be gotten from redressed AC or from any DC supply. It is valuable where electrical disengagement isn't required between the exchanging circuit and the result, however where the information is from an amended AC source, separation between the AC source and the rectifier could be given by a mains confining transformer.

The exchanging semiconductor between the information and result of the Buck Converter consistently turns on and off at high recurrence. To keep a ceaseless result, the circuit utilizes the energy put away in the inductor L, during the on times of the exchanging semiconductor, to keep providing the heap during the off periods. The circuit activity relies upon what is now and then additionally called a Flywheel Circuit. This is on the grounds that the circuit acts rather like a mechanical flywheel that, given routinely divided beats of energy continues turning without a hitch (yielding energy) at a consistent rate.

AC or DC Input

The buck converter is a type of DC to DC converter that can take an info straightforwardly from a DC source, like a battery. The info could likewise be DC gotten from the AC mains (line) as displayed in Fig. 3.1.1 through a rectifier/repository capacitor circuit. The AC contribution to the rectifier circuit could be AC at high voltage straightforwardly from the AC mains supply, or then again at a lower voltage by means of a stage down transformer. Anyway the DC applied to the Buck Converter is acquired, it is then changed over to a high recurrence AC, utilizing an exchanging or 'chopper' semiconductor, driven by a (typically beat width balanced) square wave. This outcomes in a high recurrence AC wave, which can then be re-changed over to DC in a significantly more productive way than would be conceivable in the circuits portrayed in power.

What is boost converter?

The boost converter is the opposite of buck converter, it will do voltage step up from input voltage, if 12v supplied to it, than it step up voltage and give high voltage, output voltage we can adjust and fixed by own requirement.

The buck and boost converter or circuits works same as a transformer, but where the transformer only works by "AC current and buck or boost converter can works at both currents such as "AC and "DC".

The buck and boost converter mostly used in computer and laptops, because a computer/laptop has many different electronics parts which requires different voltage level, such as Ram, DVD room, USB port, LCD's signal, small lights, etc. Require different voltage, and this only possible by a Buck converter circuit.

How to works a buck circuit

This buck circuits has four main components which is Transistor, Diode, Inductor and Capacitor, and this circuit works at switching mode. 

Buck converter circuit

Which figure you saw above this is the circuit of Buck converter.

So when its switch "ON" then current will pass, and if switch will be "OFF" then current will can not flow, this means if this switch remain "ON" condition so voltage flows but when switch "OFF" than voltage be "0v".

So if this switch will switching quickly then voltage can decrease, because if this switch "ON" and "OFF" many time so voltage will can't remain full, and voltage will decrease.

For this we used a transistor place of switch because Transistor can switching quickly, so when voltage switching quickly by transistor then voltage frequency will be high, for this we used a inductor and capacitor for current filtering, because the "DC" current has zero frequency, if inductor and capacitor not used then "DC" load will not run smoothly.

And diode used for current maintenance so that when transistor switched "OFF" then current can easily return.

And transistor controlled by PWM circuit, because voltage will adjust by switching, means if transistor frequency will decrease or increase then voltage will be increase and decrease.