Dual-frequency MEMS oscillator — what the 20/25 MHz output means for your BOM
The DSC6121HI2A-00AET: That means one oscillator can feed a 20 MHz MCU core clock and a 25 MHz Ethernet PHY reference, reducing BOM line count and board area compared to two separate quartz cans.
The 3 mA typical supply current (max) keeps the thermal contribution negligible in a dense board layout. CMOS output swings rail-to-rail, so it drives standard logic inputs directly. The 0.89 mm seated height and 1.6 x 1.2 mm footprint fit under a shield can or on a tight mezzanine stack.
Obsolete — sourcing reality and what to expect
For a new design, a pin-compatible MEMS oscillator from the same DSC61XX family with the same dual-output configuration and package is the migration path — but the exact output frequency pair and stability grade must be matched to the BOM. No direct drop-in replacement is guaranteed without verifying the frequency plan.