StratEdge Power Amplifier Package Used on Mars Rovers
StratEdge, a leader in the design and production of semiconductor packages for microwave, millimeter-wave and high speed digital devices, announced that one of its SE20 power amplifier packages is playing a key role in transmitting signals with information gathered from Mars Exploration Rovers Spirit and Opportunity back to earth. The power amplifier package is used to protect the gallium arsenide monolithic microwave integrated circuits (MMIC) and ensure signal integrity.
All signals that are transmitted from the rovers go through a StratEdge package. The rovers communicate at X-band frequency. It is critical that the package does not interfere with the signals produced by the MMIC. The package has continuous gold traces that run through the package wall. The design of these highly conductive traces minimizes signal loss so the MMIC performs optimally. Single transition insertion loss is better than 0.1 dB at X-band.
The rugged StratEdge package is fully hermetic. The package has a copper composite base with a thermal conductivity of 170 W/m-K. The high thermal conductivity of the base reduces the junction temperature and enhances reliability of the MMIC. The package can withstand temperatures from -60 degrees to +250 degrees Fahrenheit (-16 degrees to +121 degree Celsius).
The StratEdge package was incorporated into Motorola’s electronic communications assembly. General Dynamics acquired Motorola Integrated Information Systems Group in 2001. Motorola was looking for packages with exceptional electrical performance and good hermeticity, and had previously used StratEdge packages for high reliability space applications. The rovers were launched in June and July of 2003 with a lifetime anticipated at three months once they landed on Mars. The rovers have been in service for several times their designed life.