An isolated gate driver is a special category of driver normally used for high-power (kilowatt) applications. The primary functions of the driver are: boost the strength of the microcontroller or DSP output signal, increase the voltage swing from 3.3 V up to +18 V (and sometimes down to -5 V during turn off), and raise the current level from 3 mA to 3 A or more. It provides the high current necessary to quickly turn on (charge) and turn off (discharge) an IGBT or MOSFET power device. An isolated gate driver delivers good isolation, separating the low-level microcontroller output signals from the DC bus voltage (often called DC Link).