100V half-bridge gate driver for GaN power FETs from National Semiconductor

National Semiconductor Corp. has introduced the 100V half-bridge gate driver optimized for use with enhancement-mode Gallium-Nitride (GaN) power field-effect transistors (FETs) in high-voltage power converters. According to National this new LM5113 is industry's first a highly integrated, high-side and low-side GaN FET driver that reduces component count by 75 percent and shrinks printed circuit board (PCB) area by up to 85 percent compared to discrete driver designs.

Designers of power bricks and communications infrastructure equipment require high power efficiency in the smallest form factor. Enhancement-mode GaN FETs enable new levels of efficiency and power density compared to standard metal-oxide semiconductor field-effect transistors (MOSFETs) due to their low on-resistance (Rdson) and gate charge (Qg) as well as their ultra-small footprint, but driving them reliably presents significant new challenges. National says its LM5113 driver integrated circuit (IC) eliminates these challenges, enabling power designers to realize the benefits of GaN FETs in a variety of popular power topologies.

"National's LM5113 bridge driver helps designers unleash the performance of eGaN FETs by simplifying the design," said Alex Lidow, co-founder and CEO for Efficient Power Conversion Corporation. "The LM5113 dramatically reduces component count, and paired with our eGaN FETs, enables a tremendous PCB area savings and higher level of power density versus equivalent MOSFET-based designs."

Technical Features of the LM5113 Bridge Driver:

LM5113 regulates the high side floating bootstrap capacitor voltage at approximately 5.25V to optimally drive enhancement-mode GaN power FETs without exceeding the maximum gate-source voltage rating. The LM5113 also features independent sink and source outputs for flexibility of the turn-on strength with respect to the turn-off strength. A low impedance pull down path of 0.5 Ohms provides a fast, reliable turn-off mechanism for the low threshold voltage enhancement-mode GaN power FETs, helping maximize efficiency in high frequency power supply designs. The LM5113 features an integrated high-side bootstrap diode, further minimizing PCB real estate. The LM5113 also provides independent logic inputs for the high-side and low-side drivers.

Package: 10-pin 4 mm by 4 mm LLP package
Price: Cost US$1.65 each in quantities of 1,000
Availability: Now in samples, volumes in September

For more information, visit http://www.national.com/pf/LM/LM5113.html