A broadband low cost GaN-on-silicon MMIC amplifier

The design and performance of a 0.1 to 5 GHz medium power distributed amplifier is described. The circuit is realized using a low-cost GaN-on-silicon MMIC process featuring 0.5 mum gate length GaN HFETs on a 150 mum thick high resistivity silicon substrate. The circuit was designed using a non-linear FET model and standard passive component models. The first pass circuit demonstrates a saturated output power of 2 W and a maximum efficiency of greater than 30% at 1 GHz at a drain bias of 15 V, and a saturated output power of 3 W and maximum efficiency of 23% at 2.5 GHz with a drain bias of 28 V.