特性
- Designed for use in SAS, SAS-2, and SATA systems
- Center (±0.25%) Spread Spectrum Clocking (SSC)
- Down (-0.23% or -0.5%) SSC
- Better frequency stability than SAW oscillators
- One differential 2.5V LVDS output
- Crystal oscillator interface designed for 25MHz (CL = 18pF) frequency
- External fundamental crystal, ensures high reliability and low aging
- Selectable output frequencies: 75MHz, 100MHz, 150MHz, 300MHz
- Output frequency is tunable with external capacitors
- RMS phase jitter @ 100MHz, using a 25MHz crystal (12kHz – 20MHz): 1.1936ps (typical)
- 2.5V operating supply
- -40°C to 85°C ambient operating temperature
- Available in lead-free (RoHS 6) packages
844441I - Block Diagram
描述
The 844441I is a low jitter, high performance clock generator and a member of the FemtoClock® family of silicon timing products. The 844441I is designed for use in applications using the SAS and SATA interconnect. The 844441I uses an external, 25MHz, parallel resonant crystal to generate four selectable output frequencies: 75MHz, 100MHz, 150MHz, and 300MHz. This silicon based approach provides excellent frequency stability and reliability. The 844441I features down and center spread spectrum (SSC) clocking techniques.
