The ICS840002-01 is a LVCMOS/LVTTL frequency synthesizer optimized to generate Ethernet reference clock frequencies. It uses a 25MHz 18pF parallel resonant crystal, and can generate frequencies of 156.25MHz, 125MHz, and 62.5MHz based on the frequency select pins (F_SEL1:0). The ICS840002-01 utilizes ICS' 3rd generation low phase noise VCO technology and can achieve 1ps or lower typical random rms phase jitter, meeting Ethernet jitter requirements.
The ICS840002-01 FemtoClocks™ crystal‑to‑LVCMOS/LVTTL frequency synthesizer provides two LVCMOS/LVTTL outputs optimized for Ethernet reference clock frequencies. It uses a 25 MHz 18 pF parallel resonant crystal and selectable frequency pins to generate 156.25 MHz, 125 MHz, or 62.5 MHz outputs with typical jitter below 1 ps.
The device is supplied in a 16‑lead TSSOP package, operates from –30 °C to 85 °C, and offers separate core and output supply rails (3.3 V core with 3.3 V or 2.5 V output). Detailed pin descriptions, electrical characteristics, and application guidelines are included for board designers.
| Output frequency range | 6 MHz – 175 MHz |
|---|---|
| VCO range | 6 MHz – 70 MHz |
| Output skew | 12 ps (max) |
| RMS phase jitter (156.25 MHz) | 0.47 ps (typical) |
| Phase noise @ 100 Hz | -97.4 dBc/Hz |
| Supply voltage options | Full 3.3 V or 3.3 V core/2.5 V output |
| Operating temperature | -30 °C to 85 °C |
| Package dimensions | 4.4 mm × 5.0 mm × 0.92 mm |
| Number of outputs | Two LVCMOS/LVTTL outputs |
It can be powered with a full 3.3 V supply or with a 3.3 V core and a 2.5 V output supply mode.
The device provides two LVCMOS/LVTTL outputs.
Selectable frequencies are 156.25 MHz, 125 MHz, and 62.5 MHz, set by the F_SEL pins.