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SiRFstarIII™ 20-channel GPS SMD compact module/receiver with enhanced high altitude power saving modes.

The ISM300F2-C5-V0004 module is programmed with HIGH ALTITUDE BUILD, ceiling 135,000 feet, and works at cold temperatures for balloon applications.


  • SiRF Binary at 57600 baud on port A
  • NMEA at 4800 baud on port B
  • Maximum altitude of 42000 meters (137795 ft)
  • 18mm X 18mm x 3mm
  • Surface Mount Component.

More information to come. Used on Ava flight computer. Project Ava

External link : ISM300F2-C5-V0004

Eagle Schematics for Breakout Board / device for ISM300F2

The following files were created based on Upu's original board for the ISM300F2 chip:

Expect to see a “Board and schematic are not consistent” error when you open this. Ignore it, the board works fine.

The number of pins were reduced from 8 to 5, since several of the busses are now connected. The 5th pin, the ON/OFF pin, is optional, and the board will work even if this pin is not soldered to anything. It was left open for anyone with a desire to control the power consumption of the chip to be able to use it, per Inventek's guide.

Here's an image of the board as it appears in Eagle:

guides/inventek-ism300.1311697560.txt.gz · Last modified: 2011/07/26 16:26 by nickolai