SparkPNT GNSS Disciplined Oscillator Delivers Sub-Nanosecond Timing

SparkPNT GNSS Disciplined Oscillator Plus

SparkFun Electronics has launched its inaugural ultra-high-precision GNSS timing product, the SparkPNT GNSS Disciplined GNSS(GNSSDO). The GNSSDO+ is based on Septentrio’s multi-constellation, multi-frequency, L1/L2/L5-ready mosaic-T module and is aimed at applications requiring sub-nanosecond timing and frequency precision. GNSSDO+ is built around the Espressif ESP32-WROVER processor (16MB flash, 8MB PSRAM). The GNSSDO+ features the STP3593LF Double-Oven OCXO from Rakon to deliver ultra-precise timing output, enhanced frequency stability and the ability to receive the AtomiChron timing correction service for accuracy better than 1ns.

The mosaic-T has USB-C connectivity (with Ethernet-over-USB) and multiple UARTs, and supports full Ethernet connectivity. The Septentrio mosaic-T provides a remarkably accurate conventional method for time and frequency synchronization under challenging conditions such as during GNSS jamming or spoofing. The timing accuracy of GNSSDO+ is impressive. Its time pulse measurement precision is 5 ns, or less than 1 ns with an optional subscription to Fugro AtomiChron via L-Band. Event accuracy is below 20 nanoseconds. Additionally, the integration of SiTime’s Super-TCXO provides improved clock frequency stability and accuracy during GNSS blackouts.

SparkPNT GNSS Disciplined Oscillator Ports

SparkPNT GNSS Disciplined Oscillator Plus Specifications:

• GNSS Timing Receiver:
  • Equipped with the Septentrio mosaic-T multi-constellation, multi-frequency GNSS timing receiver
  • Features dedicated timing capabilities for high-accuracy synchronization applications
  • Supports AIM+ interference mitigation technology and Fugro AtomiChron® services for enhanced protection against jamming and spoofing
  • GNSS update rate of up to 10 Hz
  • Includes 448 hardware channels for simultaneous tracking of all visible satellite signals
• Supported GNSS Signals:
  • GPS: L1C/A, L1PY, L2C, L2P, L5
  • GLONASS: L1CA, L2CA, L2P, L3 CDMA
  • BeiDou: B1I, B1C, B2a, B2b, B2I, B3
  • Galileo: E1, E5a, E5b, E5 AltBOC, E6
  • QZSS: L1C/A, L1C/B, L2C, L5
  • NavIC: L5
  • SBAS: EGNOS, WAAS, GAGAN, MSAS, SDCM (L1 and L5)
  • Integrated L-band receiver
  • RTK Base mode and RTCM output are not supported
• Timing Performance:
  • Time pulse precision: 5 ns
  • Time pulse precision with AtomiChron (L-Band/IP): better than 1 ns
  • Event timestamp accuracy: below 20 ns
• Processing Hardware:
  • Espressif ESP32-WROVER module
  • 16 MB Flash memory
  • 8 MB PSRAM
  • USB-C connectivity via CH340 UART bridge
• Disciplined Oscillator:
  • STP3593LF disciplined 10 MHz oscillator
  • Frequency calibration accuracy better than 50 ppb at 25°C
  • Aging stability of ±0.2 ppb per day
  • Temperature stability of ±0.03 ppb from -32°C to +70°C
  • Digital frequency adjustment through I²C interface
  • Allan Deviation below 1E-14 at 10,000 seconds when AtomiChron is enabled
• Networking:
  • KSZ8041NLI Ethernet PHY
  • Supports 10Base-T and 100Base-TX Ethernet
  • Auto-negotiation and Auto MDI/MDI-X supported
• Storage and Display:
  • microSD card slot directly connected to the mosaic-T for high-speed data logging
  • Integrated 128 × 64-pixel OLED display
• RF and Timing Interfaces:
  • SMA connector for GNSS antenna with 3.3V active antenna power
  • 10 MHz disciplined clock output (3.3V)
  • Pulse-Per-Second (PPSO) output aligned to the 10 MHz reference
  • EventA input configurable for 5V, 3.3V, 2.8V, or 1.8V operation with 50Ω termination
• I/O Connectivity:
  • Industrial-grade 3.5 mm screw terminal connectors
  • Fully isolated DC power input (9V–36V)
  • Selectable 3.3V or 5V I/O voltage levels
  • mosaic-T COM2 UART interface:
    • TX
    • RX
    • RTS
    • CTS
  • CTS pin can optionally serve as a VCCIO voltage output
  • Additional interfaces include:
    • EVENT-B input
    • GP1 output
    • GP2 output
• Power Options:
  • USB-C power through the mosaic-T port (USB Power Delivery adapter required)
  • USB-C power through the ESP32 interface (USB Power Delivery adapter required)
  • Power-over-Ethernet (PoE): 36V–57V and External DC input: 9V–36V
• Enclosure:
  • Housed in a custom extruded aluminum enclosure with machined end panels
  • IP42-rated design; weatherproof housing required for outdoor deployment
  • Matte-finish front and rear labels
• Operating Temperature:
  • Septentrio mosaic-T: -40°C to +85°C
  • Complete oscillator subsystem: -32°C to +70°C

Technical Specifications

For the SparkFun GNSSDO+ and the Septentrio mosaic-T GNSS module, the GitHub documentation related to the Hardware and Software can be found on the Hardware GitHub Repo and ESP32 Firmware section and Septentrio resources containing the datasheet, firmware, manual, software tools, USB driver.

The SparkPNT GNSS Disciplined Oscillator Plus (GNSSDO+) is available for purchase on the Sparkfun Electronics product page priced at $3,500. For additional information, refer to the Product Manual – SparkPNT GNSSDO+ page. 

Images used courtesy of Sparkfun.