High-frequency power supplies often require high-speed high-current drivers such as the UCC27324-Q1 device. A leading application is the need to provide a high-power buffer stage between the PWM output of the control device and the gates of the primary power MOSFET or IGBT switching devices. In other cases, the driver is used to drive the power device gates through a drive transformer. Synchronous rectification supplies must also simultaneously drive multiple devices, which can present an extremely large load to the control circuitry.

Drivers are used when using the primary PWM regulator to directly drive the switching devices is not feasible for one or more reasons. The PWM device may not have the brute drive capability required for the intended switching MOSFET, limiting the switching performance in the application. In other cases, minimizing the effect of high-frequency switching noise by placing the high-current driver physically close to the load may be necessary. Also, newer devices that target the highest operating frequencies may not incorporate onboard gate drivers at all. The PWM outputs are intended to drive only the high-impedance input to a driver such as the UCC27324-Q1. Finally, the control device may be under thermal stress because power dissipation, and an external driver can help by moving the heat from the controller to an external package.