Militarized Chip-Scale Atomic Clock (CSAC)
Peter Cash, Igor Kosvin, Paul Machado, Mike Silveira, and Gary Wernsing, Microchip Technologies
Location: Ballroom E
Date/Time: Wednesday, Aug. 25, 11:30 a.m.
Microchip’s Model SA.45 Chip-Scale Atomic Clock (CSAC) provides accurate low-power frequency and timing capabilities to portable, volume constrained, severe environmental applications. Microchip has updated the CSAC, the SA65, to support military applications in demanding environments. The SA.65 CSAC provides operation over a wider temperature range, improved temperature stability, longer hold-over time, improved phase noise, and reduced time to atomic lock. This paper will describe the updates to the hardware and firmware design. Design improvements include optimizing microwave coupling to the physics package, improved voltage regulation, increased heater demand power for rapid warm-up, and enhancements to the atomic clock control algorithms. In parallel, Microchip is developing a companion variant of the SA65 CSAC with superior phase noise for radio applications. The improved phase noise is a result of incorporating a low-power Ovenized Crystal Oscillator (OCXO) in place of the Temperature-Compensated Crystal Oscillator (TCXO) as the primary local oscillator for atomic interrogation. The paper will summarize the results of environmental testing of the SA.65 CSAC, including thermal and thermal vacuum, phase noise and frequency stability performance during random vibration, mechanical shock resilience and performance, and extended high-temperature life testing.