Programmable blank — what it means for procurement
The DSC8121AI5: This part ships as a blank (user-programmable) device — it does not come pre-configured to a specific frequency. The buyer must program it using Microchip's TimeFlash or a compatible programmer before it can serve as a clock source on the board. The available frequency range is 10 MHz to 100 MHz, so a single BOM line can cover multiple clock frequencies by programming the same blank part at different values. That reduces line-item count if your design uses several different oscillator frequencies.
Package and board-fit — 7.0×5.0 mm footprint
That is a standard large-can oscillator footprint — compatible with many existing PCB layouts that use a 7×5 mm XO.