GNSS time synchronization support for IIS3DWBG1/IIS3DWBG1TR and AIS25BA/AIS25BATR
Hello,
I am evaluating IIS3DWBG1/IIS3DWBG1TR and AIS25BA/AIS25BATR for a data acquisition system where sensor data timestamps need to be aligned with GNSS time.
I would like to ask whether these devices support any GNSS-related time synchronization interface or equivalent mechanism, such as GNSS/GPS 1PPS or PPS input, UTC/NMEA time reference input, PTP/IEEE1588 synchronization, external sync input, external reference clock input, FSYNC/CLKIN/EXTCLK, or any pin/register mechanism that can reset, latch, align, or discipline the internal timestamp counter using an external timing signal.
Based on my review of the publicly available ST documentation and product pages, IIS3DWBG1/IIS3DWBG1TR appear to provide an internal timestamp counter and FIFO timestamp function, but I have not found any clearly documented pin, register, or configuration mechanism to align this timestamp to GNSS 1PPS/PPS or UTC time.
For AIS25BA/AIS25BATR, the publicly available documentation shows TDM interface signals such as TDM_MCLK, TDM_BCLK, TDM_WCLK and TDM_SDOUT. My current understanding is that TDM_WCLK is a TDM word/frame synchronization signal, not an absolute GNSS/PPS time synchronization input.
If GNSS-aligned timestamps are required, my current understanding is that timestamp alignment may need to be implemented externally in the host MCU, processor, or data acquisition system, for example by timestamping DRDY/FIFO readout using a GNSS/UTC/1PPS reference.
Could anyone from the community or ST moderators help check whether this understanding is correct?
Also, if there are any application notes, reference designs, or recommended implementation methods for GNSS-synchronized timestamping with these devices, I would appreciate the guidance.
Thank you.