A Power-On-Reset Circuit With Accurate Trigger-Point Voltage and Ultralow Typical Quiescent Current for Emerging Nonvolatile Memory

In this article, a power-on-reset (POR) circuit with accurate trigger-point voltage and ultralow typical quiescent current for emerging nonvolatile memory (NVM) is presented. To keep the trigger-point voltage from the effect of process, voltage, and temperature (PVT) and supply ramp rate variations, low-cost current generators and a current comparator are adopted with brown-out detection (BOD). A protection circuit is utilized for correct operations in different BOD events. Meanwhile, delay blocks are utilized to generate reliable pulse signals that are less influenced by temperature and supply ramp rate. The simulation results show that the trigger-point voltage is 2.08 V with a temperature coefficient (TC) of 81.8 ppm/°C and a deviation to the ramp time of 9.91% for a wide ramp time range from
$10 ~\mu \text{s}$
to dc. In addition, the reset duration time of the POR pulse is also reliable. The proposed POR circuit designed in the 55-nm CMOS process consumes only 0.65-nA typical quiescent current and
$59\times 146\,\,\mu \text{m}$
area, which is suitable for emerging NVM systems.