ICS840004-01 Datasheet | Integrated Circuit Systems

PRELIMINARY Integrated Circuit Systems, Inc. FEMTOCLOCKS™ CRYSTAL-TOLVCMOS/LVTTL FREQUENCY SYNTHESIZER Features - Four LVCMOS/LVTTL outputs, 15Ω typical output impedance - Selectable crystal oscillator interface or LVCMOS/LVTTL single-ended input - Output frequency Range: 56MHz - 175MHz - VCO Range: 560MHz - 700MHz - RMS phase jitter at 156.25MHz (1.875MHz - 20MHz): 0.52ps (typical) design target Phase noise: Offset Noise Power GENERAL DESCRIPTION The ICS840004-01 is a 4 output LVCMOS/LVTTL Synthesizer optimized to generate Ethernet Hi Per Clock S™ reference clock frequencies and is a member of the Hi Per Clocks TM family of high performance clock solutions from ICS. Using a 25MHz, 18p F parallel resonant crystal, the following frequencies can be generated based on the 2 frequency select pins (F_SEL1:0): 156.25MHz, 125MHz, and 62.5MHz. The ICS840004-01 uses ICS’ 3rd generation low phase noise VCO technology and can .. achieve 1ps or lower typical random rms phase jitter, easily meeting Ethernet jitter requirements. The ICS840004-01 is packaged in a small 20-pin TSSOP package. IC S 100Hz ............... -94.9 d Bc/Hz 1k Hz ............. -119.6 d Bc/Hz 10k Hz ............. -128.9 d Bc/Hz 100k Hz ............. -129.2 d Bc/Hz - Full 3.3V or 3.3V core/2.5V output supply mode - 0°C to 70°C ambient operating temperature - Available in both standard and lead-free Ro HS-pliant packages FREQUENCY SELECT FUNCTION TABLE F_SEL1 F_SEL0 0 0 1 1 0 1 0 1 ETHERNET FREQUENCIES M/N Ratio Value 6.25 5 2.5 5 Output Frequency (25MHz Ref.) 156.25 125 62.5 12 5 Inputs M Divider N Divider Value Value 25 4 25 25 25 5 10 5 BLOCK DIAGRAM OE Pullup F_SEL1:0 Pullup:Pullup n PLL_SEL Pulldown n XTAL_SEL XTAL_IN Pulldown 25MHz PIN ASSIGNMENT F_SEL0 nc n XTAL_SEL TEST_CLK OE MR n PLL_SEL VDDA nc VDD 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 F_SEL1 GND Q0 Q1 VDDO Q2 Q3 GND XTAL_IN XTAL_OUT XTAL_OUT TEST_CLK Pulldown F_SEL1:0...