Modeling and realization of a wideband LNA based on LTCC technology

A wideband low noise amplifier integrated into a LTCC (Low Temperature Co-Fired Ceramic) environment is presented in this paper. 50ohm microstrip lines are simulated using 3D full-wave simulator, which takes into account the electromagnetic effects caused by top conductors recess. To integrate bare chips into LTCC substrates, an entire passive structure of the LNA including bond wires and via arrays is designed and optimized, with bond wires for interconnection from MMIC chips to microstrip lines and via arrays for grounding between different ground planes. An equivalent pi-type model for two-parallel bond wires is analyzed and parameters of the model are extracted. The pitch of via arrays is studied to obtain good grounding performance. To implement an overall simulation of the LNA EM (electromagnetic)-based data of the full passive structure are exported into ADS and are cascaded with S parameter data of MMIC. The measured results show the LNA has a 20dB gain, a 7dB return loss and a 2.6dB noise figure from 8 GHz to 20 GHz. Good agreement between simulated and measure results is achieved.