Power-on-reset and supply brown out detection circuit with programmability

摘要

A low-power wideband Power-on-Reset (PoR) and supply brown out detection circuit is proposed, wherein a technique for accurately controlling the PoR trip points and hysteresis voltage is presented. The PoR circuit includes a CMOS circuit with asymmetric rise and fall delays for monitoring wideband supply voltage transients including supply brown out. Being a non-bandgap and non-comparator based circuit, it consumes a very small power and Si area.

主权项

1. A device comprising:
a supply voltage detector configured to set programmable trip points and to set a programmable hysteresis voltage, to detect a supply voltage level and to produce an active low internal reset signal depending on the detected supply voltage level, the programmable trip points and the programmable hysteresis voltage, wherein the supply voltage detector comprises:
a power down PMOS transistor;a reference voltage generator coupled to the power down PMOS transistor and configured to generate a reference voltage;a first inverter configured to receive the reference voltage as its input to produce an active high internal reset signal; anda second inverter configured to receive the active high internal reset signal as its input to produce the active low internal reset signal; and a delay circuit configured to receive the active low internal reset signal and to introduce delays on rising and falling edges of the active low internal reset signal to produce a final active low reset signal.