HCI-Proof Ultra-Broadband Millimeter-Wave Amplifier for Automotive Radar

In this paper, a circuit configuration to solve the problem of hot carrier injection (HCI) in a millimeter-wave amplifier is proposed. It is necessary to drive the LO-terminal of a mixer with sufficient voltage swing, but as it is generally known, there is the problem of HCI in CMOS transistors. Applying voltage exceeding the HCI limit to a transistor will accelerate the degradation of the transistor. Therefore, we controlled the output power of the driver amplifier to adjust the voltage swing to an allowable range. Furthermore, by controlling the output power, a wide range of frequency flatness from 72 GHz to 88 GHz has been achieved. This circuit is fabricated in 40-nm CMOS.