A 1μm CMOS eight-bit integrated circuit was designed and fabricated

used for sampling

weighting

controlling and summing of both SAW delay lines and SAW IDTs in multi-chip module (MCM) programmable SAW filter.Its characteristics and performances are simulated and tested.The circuit of each bit consists of two sampling capacitances which are made in sandwich structure of two layers of Al and one layer of poly-silicon and also consists of two high transconductance N-MOSFETs with high W/L ratio.The circuit is simple and compatible with traditional CMOS processes.Its insertion loss is about -8dB~-20dB within 15MHz~250MHz frequency and the weighted circuit's on/off ratio is within the range from 7dB to 18dB.