The DSC1001BI5-125.0000T is a MEMS-based XO (Standard) oscillator from Microchip's DSC1001 series, delivering a 125 MHz CMOS clock with ±10ppm frequency stability across -40°C to 85°C.
Supply voltage range 1.8V to 3.3V lets the oscillator run directly off a 1.8V core rail or a 3.3V I/O rail without an extra LDO — handy when the same BOM has both voltage domains. Active current draw is 8.7mA max at 125 MHz — low enough that a 100mA LDO can power this plus a small MCU and some pull-ups without exceeding the regulator's rating.
Housed in a 4-SMD, No Lead package measuring 5.00mm x 3.20mm with a seated height of 0.90mm — a standard footprint that matches many quartz oscillators, so the PCB layout doesn't need a spin when switching from quartz to MEMS.