Abstract: In RF systems, the down converter is a commonly used component, which is mainly used for the detection and reception of RF signals. A downconverter for the 6-18 GHz frequency band is designed in this paper. The down converter uses a hybrid integrated circuit technology with processing bandwidth 1 GHz and the noise figure is better than 6 dB. The amplitude consistency is within ±2 dB and the phase consistency within ±15° between the different components. Besides, the no false dynamic range is larger than 50 dB. The component uses multi-function chips, MEMS filter bank, built-in digital attenuators and a digital phase shifter. The component possesses advantages of wide frequency band, small size, high integration, and easy production.