Ultra-low power analog & digital circuit

- 5nW crystal oscillator for ultra-low power sensor systems: The quartz crystal oscillator is known for its excellent frequency stability. However, with a conventional circuit, the power required to maintain the oscillation is too high to be used under stringent energy budget of the ultra-low power wireless sensor nodes system. Therefore, we incorporated new techniques to bring the power consumption as low as 5nW without impacting the freqeuncy stability characteristic provided by the crystal. The details were presented in 2012 ISSCC.