The HMC939A from Analog Devices is a RF Variable Attenuator with Frequency 0.1 to 40 GHz, Attenuation Range 1 to 31 dB, Attenuation Step 1 dB, Attenuation Accuracy ±1 dB, Power 21 to 24 dBm (P0.1dB). Tags: Die, Digital. More details for HMC939A can be seen below.