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UBX-M8030-KT-FT chip

u-blox M8 time & frequency reference GNSS chip

Leading performance under poor signal conditions

  • Concurrent reception of GPS/QZSS, GLONASS, BeiDou
  • Direct control of system reference oscillator disciplined by GNSS
  • Accurate measurement and control of external oscillators
  • Industry leading acquisition sensitivity and single‑satellite timing
  • Automatic hold‑over
  • Prepared for integration with external PTP, Sync‑E and network listen

Product variants


u-blox M8 GNSS chip, Time & Frequency
reference, 40 Pin QFN

Product variantsUBX-M8030-KT-FT
Concurrent GNSS
GNSS features 
OscillatorCrystal supported, TCXO supported
Pin (active) for external antenna
Pin (passive) for external antenna
DDC (I²C compliant)1
Electrical data 
Minimum supply [V]3.00
Maximum supply [V]3.6
Environmental data, quality & reliability 
Maximum temperature [°C]85
Minimum temperature [°C]-40
Size [mm] 5 x 5 x 0.59
Programmable flash memory
Data logging
RTC crystal
Internal oscillator
MarketsSmart Cities, Infrastructure


Product Summary

Interface Manual

Application Note

White Paper

Driver Guide

Release Notes

End of Life Note


User Guide

u‑blox time and frequency products provide multi‑GNSS synchronization for cost‑sensitive network edge equipment including Femto wireless base‑stations. The M8030‑KT‑FT IC provides a complete GNSS receiver and reference frequency control function. This single‑chip RF and baseband IC requires few external components: just a low‑cost SQI Flash for program and parameter storage and passive components. The M8030‑KT‑FT can control a system reference VCTCXO directly via its in‑built PWM DAC, providing both frequency and phase coherence with the best available source of synchronization. Additional remote oscillators may be controlled via a second DAC (DDC) or via the host system. External sources of synchronization are supported through time‑pulse and frequency inputs and a message interface. This allows measurements from macro‑sniff, Sync‑E, or packet timing to be combined with measurements from GNSS. u‑blox time and frequency products include timing integrity alarms that report phase and frequency uncertainty both during normal operation and hold‑over. They feature a high dynamic range radio with both analog and digital interference mitigation supporting their inclusion as an integral part of a local area base station design. Example application (Residential Femto Cell) In a Femto‑Cell application, the M8030‑KT‑FT can make fine adjustments to the master reference frequency oscillator to precisely align the Femto‑cell transmit framing with a phase reference from GNSS or PTP. In the absence of a reliable source of synchronization, the M8030‑KT‑FT automatically manages hold‑over based on the stability of the oscillator selected, allowing the Femto‑cell to continue transmissions. The M8030‑KT‑FT estimates phase and frequency uncertainty continuously during hold‑over so the host system can decide when to discontinue transmission.