845264

FemtoClock®Crystal-to-CML Clock Generator 845264 DATA SHEET General Description The 845264 is a 3.3V, 2.5V CML clock generator designed for Ethernet applications. The device synthesizes four clock frequencies on two separately selectable output banks. Each bank has either a 62.5MHz, 125MHz, 156.25MHz or 312.5MHz clock signal with excellent phase jitter performance. Each clock frequency is distributed to two low-skew differential CML output banks with a total of four outputs. The device is suitable for driving the reference clocks of Ethernet PHYs. The device supports 3.3V and 2.5V voltage supply and is packaged in a small, lead-free (RoHS 6) 32-lead VFQFN package. The extended temperature range supports telecommunication, wireless infrastructure and networking end equipment requirements. Features Clock generation of: 62.5MHz, 125MHz, 156.25MHz and 312.5MHz Two banks of two differential CML clock outputs Crystal interface designed for 25MHz, 12pF parallel resonant crystal RMS phase jitter @ 125MHz, using a 25MHz crystal (1.875MHz – 20MHz): 0.486ps (typical) Offset Single-side Band Phase Noise 100Hz ............................-97 dBc/Hz 1kHz...............................-118 dBc/Hz 10kHz.............................-125 dBc/Hz 100kHz...........................-123 dBc/Hz LVCMOS interface levels for the control inputs Full 3.3V and 2.5V supply voltage Lead-free (RoHS 6) 32 VFQFN packaging -40°C to 85°C ambient operating temperature Block Diagram nO...