  Recently, harvesting natural energy is gaining more attention than other
conventional approaches for sustainable Internet-of-Things (IoT). System on
chip (SoC) power requirement for the IoT and generating higher voltages on-chip
is a massive challenge for on-chip peripherals and systems. Many sensors are
employed in smart cities and smart villages in decision-making, whose power
requirement is an issue, and it must be uninterrupted. Previously, we presented
Security-by-Design (SbD) principle to bring energy dissipation and
cybersecurity together through our "Eternal-Thing". In this paper, an on-chip
reliable energy harvesting system (EHS) is designed for IoT end node devices
which is called "Eternal-Thing 2.0". The management section monitors the
process load and also the recharging of the battery or super-capacitor. An
efficient maximum power point tracking (MPPT) algorithm is used to avoid
quiescent power consumption. The reliability of the proposed EHS is improved by
using an aging tolerant ring oscillator. The proposed EHS is intended and
simulated in CMOS 90nm technology. The output voltage is within the vary of
3-3.55V with an input of 1-1.5V. The EHS consumes 22 micro Watt of power, that
satisfies the ultra-low-power necessities of IoT sensible nodes.
