June 22, 2020

The DPH153-AT Femtocell - GPS traffic

The GPS chip on my Femtocell is a SiRF GSC3f/LPx

When searching on PSRF100, which are proprietary commands for this chip, I found some datasheets on the Sparkfun site, which led me to look at what they offer for GPS products with this chipset.

EM-506

This is a $39 module with the SiRF Star IV chipset. This is a 48 channel receiver (mine is only 12 channels). This module adds voltage regulators, battery backed ram and such. The datasheet dates from 2013.
  • EM506 - Star IV datasheet (PDF, 20 pages)

    My GSC3f/LPx

    The datasheet says it is a 20 channel unit. It uses 60 mW maximum. It has a 1.2 volt core. You can supply it with 2.85 volts and let it use internal regulators, or bypass them and directly supply the core with 1.2 volts. The spec on the power supply is 2.7 to 3.0 with an absolute maximum of 3.15. IO pins look to be 5 volt compliant.
    Have any comments? Questions? Drop me a line!

    Tom's electronics pages / tom@mmto.org