An integrated T/R switch designed to protect low-noise amplifier (LNA) circuits in CMOS transceivers is reported. A 1.5-V 3-5 GHz low-noise amplifier utilizing on-chip transformer and gain boosting in cascode stage is fabricated by TSMC 0.18um CMOS process. The transformer-based LNA is realized with a LC ladder filter circuit to achieve the wideband input matching to the source impedance of antenna, whereas the cascode stage with a shunting peaking coil provides a flat and high power gain. The output stage with a diode-connected load matches the measured instrument. This proposed chip also merger T/R-Switch design on single RFIC solution on 3-5 GHz by electronic design automation (EDA) form computational intelligence techniques.