Dual 100 MHz clock from a MEMS resonator
The DSC400-0244Q0009KE2 delivers two 100 MHz outputs from a MEMS resonator — one HCSL, one LVPECL — in a single 20-VFQFN package. That means one oscillator can feed both a PCIe reference clock (HCSL) and a SerDes PLL (LVPECL) without a second can or a level translator.
±25 ppm frequency stability over -20 to +70 °C is typical for 1 GbE, PCIe Gen 1/2, and SATA reference clocks — the timing budget for those interfaces lands around ±50 ppm total, so this oscillator leaves margin for the PLL jitter and board skew. The 2.25 V to 3.6 V supply range covers both 2.5 V and 3.3 V rails without an intermediate regulator — one less inductor and cap on the BOM.
Package and layout: 20-VFQFN exposed pad
The 5.00 mm × 3.20 mm, 20-lead VFQFN with exposed pad requires a thermal via pattern under the package — the pad is the primary heat path. The 0.90 mm height fits 1U line cards and blade servers where board-to-board clearance is tight.