Package, programming, and board-fit
The DSC8123AI2: It ships as a blank (user must program) — the frequency is set during manufacturing via Microchip's programming service or a field programmer, which means you order the base part number and specify the frequency at the time of programming, not at the distributor.
No pin-compatible second-source or successor is listed — the DSC8123 series is the sole source for this MEMS XO.
