156.2539 MHz LVPECL — clock tree fit
The DSC1122BI2-156.2539T: This is a Microchip DSC1122 series MEMS-based XO (standard oscillator) delivering a 156.2539 MHz LVPECL output. That frequency is common in 10G Ethernet, Fibre Channel, and high-speed serial backplanes—the LVPECL swing provides the edge rate needed for short PCB traces without a separate clock buffer.
For a 156.2539 MHz carrier that translates to roughly ±3.9 kHz—tight enough for most SERDES reference clock jitter budgets without external VCXO tuning. The MEMS resonator gives this oscillator better shock and vibration immunity than a quartz crystal, and the 2.25V to 3.6V supply range means it can run from a 2.5V or 3.3V rail without an extra LDO.
The 6-SMD, no-lead package (5.00mm x 3.20mm, 0.90mm seated height) is a standard footprint shared across the DSC1122 family.