The HMC391LP4 / 391LP4E from Analog Devices is a Voltage Controlled Oscillator with Frequency 3900 to 4450 MHz, Power 1.41 to 3.16 mW, Tuning Voltage 0 to 10 V, Pulling 8 MHz pp, Pushing 16 MHz/V. Tags: Surface Mount. More details for HMC391LP4 / 391LP4E can be seen below.