Boost DC to DC Converter


In many applications, a constant dc voltage source is utilized to supply dc loads. The load does not always match the available dc source, such that it could not be supplied directly by the source. In general, the specifications of the load have to be taken into account. One example is the CPU inside a laptop computer with a core-voltage of 1.8 V ±20 mV. For the functionality of the CPU, it is important to keep this voltage within the limits, no matter what the state of the CPU is (sleep, speed-step or full-load mode).

In order to fulfill this requirement, an additional component is inserted between the source and the load, which absorbs the voltage difference between the source and the load. A resistance represents a simple technical solution. It lowers the voltage at the load. However, it causes high losses at high power levels. Furthermore, the load voltage is load dependent . Another example, LCD backlights and some flashlights which need high D.C voltages to operate its cold cathode fluorecent tubes (CCFL), so an efficient converter become necessary.

DC-DC converter is an electronic circuit which converts a source of direct current (DC) from one voltage level to another. It’s used whenever we want to change DC electrical power efficiently from one voltage level to another DC to DC converters are used in portable electronic devices such as cellular phone and laptop computers, which are supplied with power from batteries primarily.

dc2

Fig.(1)

such electronic devices often contain several sub-circuits, each with its own voltage level requirement different from that supplied by the battery or an external supply (sometimes higher or lower than the supply voltage). There are many different types of DC-DC converter, each of which tends to be more suitable for some types of application than for others. For conveniece they can be classified into various groups, however. For example some converters are only suitable for stepping down the voltage (Buck Converter), while others are only suitable for stepping it up (Boost Converter); a third group can be used for either (Buck Boost Converter ).

In this project, I designed a boost DC-DC converter, which is shown in Fig.(2), to boost a 12v to 360v. Watch the video to see how this circuit is working.