US Patent 11581888 Power-on reset circuit with reduced detection time

A power-on reset circuit with reduced detection time. One example power-on reset circuit generally includes a voltage sensing circuit having an input coupled to a first power supply rail; a variable resistance component having a control input coupled to an output of the voltage sensing circuit and having a first terminal coupled to the first power supply rail; and an amplitude detection circuit having a first input coupled to the first power supply rail and having a second input coupled to a second terminal of the variable resistance component, the amplitude detection circuit being configured to generate a power-on reset signal at an output of the amplitude detection circuit based on a difference between a first voltage of the first power supply rail and a second voltage at the second terminal of the variable resistance component.