Integrated frequency-selective amplifiers for radio frequencies

The design approach for integrated selective amplifiers described here is based on a feedback configuration with a positive real zero in the loop transmission function. The basic circuit consists of two unity gain amplifiers and a transconductance block with RC imbedding. Temperature- insensitive performance, with Q values up to at least 150, at center frequencies in the RF range, is obtained for circuits fabricated with conventional diffusion and thin-film deposition techniques. Design equations are given and experimental data are reported for a 650-kHz amplifier with a Q of 50/spl plusmn/5 percent over the temperature range -10 to +110/spl deg/C.