GPS World

Tag: SA65

  • Tiny clock meets big challenges

    Tiny clock meets big challenges

    chip-scale atomic clocks can supplement GNSS receivers to provide accurate and reliable time in GNSS-challenged environments. Photo: Microchip Technology
    Chip-scale atomic clocks can supplement GNSS receivers to provide accurate and reliable time in GNSS-challenged environments. Photo: Microchip Technology

    Accurate and reliable time is just as important as accurate and reliable location for a wide range of military and civilian applications — and GNSS receivers cannot provide either one when they are jammed. For timing, one solution is to supplement GNSS receivers with a miniature atomic clock. We asked Microchip Technology a few questions about their chip-scale atomic clock (CSAC) and Stewart Hampton, the company’s senior product line manager, responded.

    How long was your SA65 CSAC in development before you announced it in August 2021? Typically, how often do you launch a new CSAC?

    CSAC development started in 2001 under a contract from DARPA with Draper and Sandia laboratories. CSAC was first introduced to the commercial marketplace in 2011, and in 2016 we released an improved product design with an operating temperature range of –10 C° to +70 C°. Last year we released our CSAC SA65 with a wider operating temperature range, faster warm-up and improved frequency stability aimed at the defense and industrial marketplace. So, it has been about five years between major CSAC releases, but that may not be indicative of future products because we have also introduced specialized CSAC versions, such as the Low Noise CSAC (LNCSAC) in 2014 and the only commercially available radiation-tolerant CSAC (Space CSAC) in 2018.

    What is the CSAC SA65’s drift rate?

    Its typical drift rate is specified at <9 × 10–10 per month. Another key specification, particularly for many portable military applications, is total sensitivity of frequency to temperature (tempco) over a specified range. For the CSAC SA65, that specification is ±3 × 10–10 over the entire operating temperature range of –40 C° to +80 C °.

    What are a few specific military use cases?

    CSAC is designed into multiple military programs and used in a wide variety of military applications, particularly in GNSS-denied environments — including assured positioning, navigation and timing (APNT) modules, underwater unmanned and autonomous vehicles, software-defined radios, man-portable transceiver-based military communications, vehicle management computers, airborne reconnaissance/UAVs and GNSS-disciplined oscillators. It is also used in command, control, communications, computers, cyber, intelligence, surveillance and reconnaissance (C5ISR). The space CSAC variant is commonly used on low-Earth-orbit space defense payloads supporting such applications as low-latency communications networks, RF geolocation (geointelligence, or GEOINT), optical time transfer, alternative PNT satellites and Earth observation.

  • Microchip offers new chip-scale atomic clock for defense

    Microchip offers new chip-scale atomic clock for defense

    New SA65 CSAC provides wider operating temperatures, faster warm-up and improved frequency stability in extreme environments

    Photo:
    Photo: Microchip Technology

    Microchip Technology Inc. is offering the new SA65 chip-scale atomic clock (CSAC), providing precise timing accuracy and stability in extreme environments. Designed for military and industrial systems, the Microchip’s SA65 CSAC features ultra-high precision and low power consumption

    Advanced military platforms, ocean-bottom survey systems and remote-sensing applications all require precise timing. CSACs ensure stable and accurate timing even when GNSS time signals are unavailable, thereby helping industrial and military system designers to meet timing requirements.

    Microchip’s SA65 CSAC is an embedded timing solution with improved environmental ruggedness, delivering higher performance than the previous SA.45s CSAC, including double the frequency stability over a wider temperature range and faster warm-up from cold temperatures. The SA65 has an operating temperature range of –40 to 80 °C and a storage temperature range of –55 to 105 °C. The warm-up time of two minutes at –40 °C is 33% faster than that of the SA.45s.

    These performance improvements benefit designers of highly portable solutions for military applications such as assured positioning, navigation and timing (A-PNT) and C5ISR (command, control, communications, computers, cyber, intelligence, surveillance and reconnaissance). It meets precise frequency requirements of a low size, weight and power (SWaP) atomic clock. Improvements such as fast warm-up to frequency after cold start, temperature stability over a wide operating range, and frequency accuracy and stability enabling extended operation while GNSS is denied help to ensure mission success in conflict environments.

    The SA65 CSAC provides precise timing for portable and battery-powered applications requiring continuous operation and holdover in GNSS-denied environments. The SA65 is form-, fit- and function-compatible with the SA.45s, which minimizes risk and redesign costs for the system developer while improving performance and environmental insensitivity.