The LTC6948-4 from Analog Devices is a Frequency Synthesizer with Frequency 700 MHz to 6.39 GHz, Reference Frequency DC to 425 MHz, Output Power -6.1 to 3 dBm, Spurious -98 dBc, Phase Noise -274 to -226 dBc/Hz. Tags: Surface Mount, PLL Frequency Synthesizer. More details for LTC6948-4 can be seen below.