The frequency 32, 768 Hz, is one of the most popular frequencies for crystal oscillators as it is used in most time keeping applications. With the proper interface circuit ( PLLs ) it can also be used for high frequency synthesizers. The actual quartz is also relatively inexpensive and this lends itself to cost effective frequency circuits and timekeeping. Of course temperature control can aso be used to generate TCXOs.

In any case, we recently designed, fabricated and throroughly analyzed a low power crystal oscillator ( in conjunction with our sister company). The circuit was first pass functional. The crystal oscillator section dissipates a mere 200 – 500 nA of current at the rated frequency.

The entire chip consists of a crystal oscillator, a low power analog buffer, a level converter and a digital output buffer capable of driving 100 pF. In addition the device has a means of trimming the frequency using an analog trim as well as a digital fine trim.

The device was evaluated thoroughly and its temperature characteristics measured extensively. Interested parties may contact us through our website at www.signalpro.biz for our experience and these results. All in all a most satisfying experience!