Patent ID: 9606563
Date: 2017-03-28
CPC Classifications: G01R,G05F,H03K

Claim:
1. A method for operating a device, the method comprising: producing a reference voltage from a source of primary power using a bandgap voltage reference circuit within the device; forming a model value of the reference voltage from a first time; comparing a present value of the reference voltage at a second time to the model value; and resetting the device when the present value is less than the model value by a threshold value; powering a detection circuit that compares the model value to the present value with a failsafe source of power, wherein the failsafe source of power is configured to provide an adequate operating voltage for the detection circuit and other critical circuitry for a period of time that is greater than the time difference between the first time and the second time; and completing a pending operation by the critical circuitry during the period of time by using the failsafe source of power.