DC-DC converters are commonly used in mobile devices such as cell phones and notebooks, which are mainly powered by batteries. These electronic devices often have many sub-circuits and require different power supply voltages than those provided by batteries or external power sources. Moreover, when the battery power is reduced, the voltage will also drop. A switching DC-DC converter can be used with a battery that has dropped in voltage to maintain the voltage of the supply circuit within a certain range, so there is no need to use multiple batteries for this purpose.
DC-DC converters, also known as choppers, add DC voltage to the load intermittently by controlling the on/off of the power electronics and changing the output voltage average by changing the duty cycle. Most DC-DC converters also regulate the output voltage, although there are some exceptions, like high-efficiency LED driver circuits that are DC-DC converters that regulate the current to the LED, and simple charge pumps that increase the output voltage to two or three times the original.
DC-DC converters can also be used in conjunction with photovoltaic arrays or wind engines, with the aim of getting the most energy collected; such devices are called power optimizers.
Generally used in the mains supply 50-60Hz transformer, if the power to exceed a few watts, its size will be large and bulky, and winding copper losses and eddy currents in the core will cause energy loss. DC-DC converters will design the circuit so that the transformer or inductor can work at higher frequencies, so the components are smaller, lighter, and more affordable in value. Even these components are used in applications where conventional mains frequency transformers were used. For example, household electrical equipment often rectify the mains power supply into direct current, use the technology of switching power supply to convert to the required voltage of high frequency alternating current, and finally rectify to the corresponding voltage of direct current. The whole circuit is more complicated than the traditional system with transformer and rectifier, but it is cheaper and the efficiency will be better.
DC-DC converters generally consist of a control chip, inductor coil, diode, transistor, and capacitor. DC-DC converters are voltage converters that effectively output a fixed voltage after transforming the input voltage. DC-DC converters are divided into three categories: step-up DC-DC converters, step-down DC-DC converters, and isolated DC-DC converters. The control type has high efficiency and good output voltage ripple and noise, and the control type has the advantage of low power consumption even when used for a long time, especially at small loads.
Currently, DC-DC converters are widely used in power conversion systems for electric vehicles such as electric cars, electric locomotives, electric motorcycles, etc. They are also commonly used in products such as cell phones, MP3, digital cameras, and portable media players. The circuit type is classified as chopper circuit.