Design and validation of an electrostatic discharge (ESD)-protected ultra-wideband low-noise amplifier (LNA) is presented in this paper. It features an interstage matching network for gain roll-off compensation to achieve a flat gain over its passband. Evaluated with a chip-on-board approach, the amplifier demonstrates a gain of 11.8 ± 0.3 dB, minimum noise figure of 2.1 dB, and a group delay variation of ±30 ps from 3 to 5 GHz, even though it uses a less advanced 0.35- micron BiCMOS technology. The LNA is protected against human body model ESD stress up to 6.5 kV. The measured input third-order intercept point at 4.5 GHz is -5.5 dBm. The core LNA draws 3 mA from a 3-V supply