The 843N252-45 is a 1 LVPECL and 1 LVCMOS output Synthesizer optimized to generate Ethernet reference clock frequencies. The device uses IDT's fourth generation FemtoClock ® NG technology for an optimum of high clock frequency and low phase noise performance, combined with a low power consumption and high power supply noise rejection. Using a 25MHz parallel resonant crystal, the following frequencies can be generated: 156.25MHz and 125MHz. With a very low phase noise VCO it is targeted to achieve 0.4ps or lower typical rms phase jitter, easily meeting Ethernet jitter requirements. The 843N252-45 is packaged in a small 16-pin TSSOP package.
Features
Fourth generation FemtoClock® Next Generation (NG) technology
One differential 3.3V LVPECL output and one LVCMOS/LVTTL output
Crystal oscillator interface designed for a 25MHz parallel resonant crystal
A 25MHz crystal generates output frequencies of: 156.25MHz and 125MHz
VCO frequency: 625MHz
RMS Phase Jitter @ 156.25MHz, (12kHz – 20MHz) using a 25MHz crystal: 0.33ps (typical)
RMS Phase Jitter @ 125MHz, (12kHz – 20MHz) using a 25MHz crystal: 0.39ps (typical)
Power supply noise rejection PSNR: -60dB (typical)
Full 3.3V supply mode
0°C to 70°C ambient operating temperature
Available in lead-free (RoHS 6) package
Comparison
Applications
Documentation
Design & Development
Models
ECAD Models
Schematic symbols, PCB footprints, and 3D CAD models from SamacSys can be found by clicking on products in the Product Options table. If a symbol or model isn't available, it can be requested directly from the website.