US Patent 9660639 Distributed driver circuitry integrated with GaN power transistors

Power switching systems are disclosed comprising driver circuitry for enhancement-mode (E-Mode) GaN power transistors with low threshold voltage. Preferably, a GaN power switch (D3) comprises an E-Mode high electron mobility transistor (HEMT) with a monolithically integrated GaN driver. D3 is partitioned into sections. At least the pull-down and, optionally, the pull-up driver circuitry is similarly partitioned as a plurality of driver elements, each driving a respective section of D3. Each driver element is placed in proximity to a respective section of D3, reducing interconnect track length and loop inductance. In preferred embodiments, the layout of GaN transistor switch and the driver elements, dimensions and routing of the interconnect tracks are selected to further reduce loop inductance and optimize performance. Distributed driver circuitry integrated on-chip with one or more high power E-Mode GaN switches allows closer coupling of the driver circuitry and the GaN switches to reduce effects of parasitic inductances.