A 70µW/MHz ultra-low voltage microcontroller SPARK

Step down DC/DC converter for micro-power medical applications

“…Different methods have been suggested to reduce power consumption of implantable electronics; one of the simplest, and highly effective is reducing the supply voltage V DD as much as possible. In the case of digital circuits it is well known that power consumption is proportional to V DD 2 . Analog circuits may also benefit from a low V DD because the performance in terms of noise, and bandwidth, among other characteristics, is generally related to current consumption rather than to power consumption [1].…”

“…A typical lithium iodine pacemaker battery can be used down to 2 V, and in the upper extreme, a fully charged lithium secondary cell can reach almost 5 V. But on the other hand, such high voltages are not strictly necessary to power the circuitry inside modern implants. Modern digital circuits can be powered with a V DD as low as 0.9 V or even less for an off the shelf microcontroller [2], meanwhile, very low voltage processors have been reported in research works like [3,4]. Also many high performance analog amplifiers, filters, and ADCs, with a supply voltage starting at a few hundred mV have been also reported.…”