The SKY72300-21 from Skyworks Solutions is a Frequency Synthesizer with Frequency 100 MHz to 2.1 GHz, Step Size 100 Hz, Supply Voltage 2.7 to 3.3 V, Current 200 µA, Phase Noise -91 dBc/Nz. Tags: Surface Mount, PLL Frequency Synthesizer. More details for SKY72300-21 can be seen below.