MIM Capacitor-Assisted Inverse Design of Nonintuitive Amplifiers

An algorithmic inverse-design technique is presented for the synthesis of nonintuitive amplifiers that enables the insertion of variable-sized metal–insulator–metal (MIM) capacitors directly into multilayered pixelated amplifier layouts. This capability expands the accessible design space and further improves the performance of pixelated radio frequency integrated circuits (RFICs). A hybrid real–binary optimization algorithm jointly co-optimizes the passive networks, transistor sizing and biasing, while autonomously determining the number, size and placement of MIM capacitors across multi-stage amplifier layouts. A SiGe HBT mm-Wave low-noise amplifier (LNA) synthesized using this approach experimentally achieves a gain–bandwidth product exceeding 1 THz with unconditional stability and a DC power consumption of 26 mW.