The HMC291 from Analog Devices is a RF Variable Attenuator with Frequency 700 MHz to 4 GHz, Attenuation Range 4 to 12 dB, Attenuation Step 12 dB, Power 0.63 W, P1dB 22 to 26 dBm. Tags: IC, Programmable, Digital. More details for HMC291 can be seen below.