40 MHz MEMS oscillator with military temperature range
The DSC1121DM1-040.0000 is a 40 MHz XO (Standard) from Microchip's DSC1121 series, built on a MEMS base resonator rather than a quartz crystal — the MEMS die is sealed at wafer level, so the oscillator survives the -55°C to 125°C military temperature band without the frequency jumps quartz exhibits near its turnover points. Rated AEC-Q100, this part carries the thermal cycling and reliability stress screening required for under-hood automotive modules, avionics black boxes, and downhole instrumentation where a standard 0°C to 70°C crystal would drift out of spec.
Supply voltage spans 2.25V to 3.6V, covering both 2.5V and 3.3V rails with headroom — a single BOM line serves designs with different core voltages, and the wide range absorbs ripple from a noisy buck converter without losing lock.
Housed in a 6-SMD no-lead package measuring 2.50mm x 2.00mm with a seated height of 0.90 mm max, the DSC1121DM1-040.0000 fits the compact 2.0 x 2.5 mm footprint common to MEMS oscillators — the no-lead land pattern eliminates the parasitic inductance of a leaded package, keeping the clock edge clean at 40 MHz.
Active product status — Microchip continues production of the DSC1121 series with no announced discontinuation.