An Ultra-Compact Switchless Bidirectional PA-LNA with 8-Shaped Transformer-Based Inter-stage Matching Networks for W-Band Applications

This paper presents an area efficient wideband bidirectional switchless PA-LNA for W-band wireless applications. The 3-stage PA-LNA employs a single signal path common-source (CS) and cascode combined circuit topology with highly efficient 8-shaped and tri-coil transformer for inter-stage and I/O matching respectively to reduce the electron-magnetic cross coupling, insertion loss and improve linearity in a compact size. The chip prototype fabricated in 40nm CMOS LP process. Thanks to the I/O and interstage matching network and careful layout optimization for both active and passive devices, the proposed bidirectional PA-LNA achieves superior performance overall: In PA mode, 13.7 dBm max Psat, 8.7 dBm max OP1dB and 9.5% peak PAE can be achieved. To the best of the authors’ knowledge, this is the first work on single-signal-path bidirectional PA-LNA using 8-shaped transformer achieving high-level of integration and cross coupling cancellation for W-band wireless applications.