ICS844246I

PRELIMINARY FEMTOCLOCKS™ CRYSTAL-TO-LVDS FREQUENCY SYNTHESIZER W/INTEGRATED FANOUT BUFFER ICS844246I GENERAL DESCRIPTION The ICS844246I is a Cr ystal-to-LVDS Clock Synthesizer/Fanout Buffer designed for Fibre HiPerClockS™ Channel and Gigabit Ethernet applications and is a member of the HiperClockS™ family of High Performance Clock Solutions from IDT. The output frequency can be set using the frequency select pins and a 25MHz crystal for Ethernet frequencies, or a 26.5625MHz crystal for a Fibre Channel. The low phase noise characteristics of the ICS844246I make it an ideal clock for these demanding applications. FEATURES Six LVDS outputs Crystal oscillator interface Output frequency range: 53.125MHz to 333.3333MHz Crystal input frequency range: 25MHz to 33.333MHz RMS phase jitter at 125MHz, using a 25MHz crystal (1.875MHz to 20MHz): 0.39ps (typical) Full 3.3V or 3.3V core, 2.5V output supply mode -40°C to 85°C ambient operating temperature Available in both standard (RoHS 5) and lead-free (RoHS 6) packages Function IC S SELECT FUNCTION TABLE Inputs FB_SEL 0 0 0 0 1 1 1 1 N_SEL1 0 0 1 1 0 0 1 1 N_SEL0 0 1 0 1 0 1 0 1 M Divide 20 20 20 20 24 24 24 24 N Divide 2 4 5 8 3 4 6 12 M/N 10 5 4 2.5 8 6 4 2 BLOCK DIAGRAM Q0 nQ0 PLL_BYPASS Pullup PIN ASSIGNMENT VDDO VDDO nQ2 Q2 nQ1 Q1 nQ0 Q0 PLL_BYPASS VDDA VDD FB_SEL 1 2 3 4 5 6 7 8 9 10 11 12 24 23 22 21 20 19 18 17 16 15 14 13 Q3 nQ3 Q4 nQ4 Q5 nQ5 N_SEL1 GND GND N_SEL0 XTAL_OUT XTAL_IN Q1 1 XTAL_IN XTAL_OUT n...