A line of monolithic-microwave-integrated-circuit (MMIC) tunable filters from Hittite Microwave Corp. covers applications from 1.0 to 7.6 GHz. The varactor-tuned filters, the firm's 25th product line, include models HMC881LP5E and HMC882LP5E, tunable, seventh-order, lowpass filters with adjustable cutoff points from 2.2 to 4.0 GHz, and 4.5 to 7.6 GHz, respectively. They are tuned by means of 0 to 14 V control signals and maintain stopband rejection of at least 35 dB beyond 30 GHz. Models HMC890LP5E and HMC891LP5E are tunable, third-order, bandpass filters with adjustable passband frequency and bandwidth by means of independent voltage controls. The two units offer adjustable center frequencies from 1 to 2 GHz and 2.0 to 3.9 GHz, respectively. Bandwidths can be adjusted within 6 percent of the center frequency. The bandpass filters maintain stopband rejection of at least 30 dB to 9 GHz. The four filter models are supplied in 5 x 5 mm QN surface-mount packages.