The ever increasing requirement for higher stabilities and performance in lower package sizes is driving innovation in reducing the Oven Controlled XOs(OCXO). The next generation synchronisation requirements on end equipment on automotive, industrial and telecom applications are pushing the performance in certain package sizes.

The paper discusses the new technology development in the area, starting with the innovation in crystal technologies. With new processing technologies enable to achieve critical quartz dimension accuracies in terms of tens of nanometer range. This allows key resonator parameters such as Q, frequency stability and unwanted modes. Technology has also moved forward on how temperature sensing can be done close to the resonators to achieve the best measurement accuracies. Combined with the techniques on low phase noise, high frequency generation and new low profiling packaging, the challenges to achieve high performances of such mini - OCXOs are outlined in the paper.