Presentation Description: This talk will first examine the unique power conversion needs in modern organic light-emitting diode television (OLED TV) displays and their impact on the design of the isolated DC/DC conversion stages used to power the OLED backlight bias, audio amplifier bias and timing/control power. The focus of the presentation will look at the use of silicon metal-oxide-semiconductor field-effect transistors (MOSFETs) and gallium nitride (GaN) in the primary side half bridge as well as in synchronous rectification (SR) in a side-by-side comparison in an OLED TV power supply unit (PSU) application. An analysis of the effects of Coss linearity, 3rd quadrant voltage, reverse recovery, etc. will be shown and their impact on the overall efficiency and regulation performance will be discussed. Lastly, test results for two power supplies (one using Si field effect transistors (FET), the other using GaN) will be presented.
