MEMS Based Shock Resilient Timing Solution for Guided Munitions

SiTime will verify the performance of our Endura TCXO a MEMS temperature compensated oscillator with ultra-low acceleration sensitivity and high shock resistance under the shock profile provided by the Army for Precision Guided Munitions (PGM). Acceleration sensitivity on existing MEMS TCXOs has been measured at 5E-12/g per axis which is about 20x better/lower than the best vibration hardened quartz oscillators which are typically 1E-10/g. This ultra-low acceleration sensitivity enables the oscillator to maintain very good short term frequency stability, quantified as Allan Deviation (ADEV), throughout the high-g launch event (up to 40,000g) which will in turn enable much faster satellite lock acquisition for the munition’s navigation system than traditional quartz oscillators.  The design target for the MEMS TCXO is 1 msec maximum residual phase error from launch until impact which is 10x lower/better than the target specification contained in A20-133. SiTime’s groundbreaking oscillator stability performance under the most severe environmental conditions places it is a unique position to satisfy and exceed the requirements of this program. In phase 1 we will model all critical parts of the mechanical construction and the MEMS resonator function. In “phase 1 option” after it is verified that the mechanical MEMS structure is still operating in its normal range we will verify the performance including full system simulation and will execute bench testing and shock testing  up to 20,000g in a quality reliability lab.