IQD Frequency Products has launched a new range of high specification crystals for specialist applications such as military, radar and pagers. Manufactured at its IQD FOQ division in Germany, the crystals are available in a variety of package styles including UM1, HC49, HC43CW (TO8) and HC45CW.
For the highest possible ‘Q’ factor, the Cold Weld (CW) packages should be specified. The ‘Q’ factor is a measurement of the loss of energy within the quartz. This is effected by the quality of the blank, surface finish (lapping), mounting technique and sealing. The maximum attainable short term stability of a crystal also depends on the ‘Q’ value.
A wide frequency range is available including 10 to 42MHz at fundamental mode, 10 to 125MHz at 3rd Overtone and 70 to 175MHz at 5th Overtone. IQD says this is pushing the design limits of quartz crystals due to the thinness of the blank that becomes unworkable beyond this.
The new range offers exceptionally low aging down to 0.1ppm per year and tight frequency tolerance @ 25 degrees C down to ±3ppm. This compares to standard crystals where typical figures would be 3ppm per year aging and ±10ppm frequency tolerance. Temperature stabilities down to 4ppm @ 0 to 70 degrees C and 12ppm @ -40 to 85 degrees C can be specified depending upon application.
Phase noise is critical in many applications and these high specification crystals offer high performance in this respect, including at high frequencies up to 100MHz at 5th Overtone.