A transformer for high-power RF applications using bondwires in parallel

A novel bondwire-transformer for high-power RF applications is presented. The proposed structure uses several bondwires in parallel, which enables ultra-low losses and high magnetic coupling. A prototype of this proposed transformer has been implemented and evaluated by full-wave electromagnetic simulations and RF measurements. Its main electrical parameters and efficiency figures of merit are considered up to 10GHz. At 2.1GHz, the measured losses and the reactive coupling factor of the fabricated prototype are better than 0.22dB (GMAX=0.95) and 0.71, respectively, while its resonance frequency is higher than 6.8GHz.