Abstract: A device and method for dc isolation and level shifting includes a driver circuit powered by a first voltage range, a capacitor connected to the driver circuit, and a latching circuit connected to the capacitor. The latching circuit is powered by a second voltage range and is configured to restore and/or minimize charge loss of the capacitor during a voltage transition at the capacitor. A device and method for analog isolation and measurement configured to measure an analog voltage at a second potential without requiring analog circuits at the second potential.

Abstract: A method is provided for accurate time measurement. Time is first measured with a first oscillator. At designated intervals, a second oscillator is activated for a period of time based on the first oscillator. The second oscillator is more accurate than the first oscillator. Pulses are then counted from the second oscillator during the period of time. The second oscillator is then turned off after the period of time. The count from the second oscillator is used as a new measurement of the period of time of the first oscillator.

Abstract: A method and apparatus for detecting an impedance across a pair of terminals. A sensing circuit is AC coupled to the terminals which produces an output related to a time constant associated with the impedance.

Abstract: A method and apparatus for detecting a change in an electrical property between contacts. A one-time operating state detection device includes a member coupling a pair of contacts and a detector for detecting a change in the coupling between the pair of contacts when the member is removed.