In aspects, the present invention discloses a method of determining an electrical operating time of a circuit breaker (140) in a multiphase electrical system having a subsystem (160) connectable to a power source (110) through a circuit breaker (140) operated by a controller (130). The controller is connected to a current transformer (120, 150) for measuring current of the subsystem in a one phase. The method comprises monitoring the current of the subsystem in the one phase, determining a first rate of change from the monitored current in the one phase, detecting an instance of switching in an another phase based on the first rate of change, and determining an electrical operating time of the circuit breaker in the another phase based on the detected instance of switching and an instance at which a command for switching in the another phase was provided to the circuit breaker.

In aspects, the present invention discloses a method of determining an electrical operating time of a circuit breaker (140) in a multiphase electrical system having a subsystem (160) connectable to a power source (110) through a circuit breaker (140) operated by a controller (130). The controller is connected to a current transformer (120, 150) for measuring current of the subsystem in a one phase. The method comprises monitoring the current of the subsystem in the one phase, determining a first rate of change from the monitored current in the one phase, detecting an instance of switching in an another phase based on the first rate of change, and determining an electrical operating time of the circuit breaker in the another phase based on the detected instance of switching and an instance at which a command for switching in the another phase was provided to the circuit breaker.

The present invention provides a method of determining an electrical operating time of a circuit breaker (140) in a multiphase electrical system having a subsystem (160) at an electric potential resulting from electrical characteristics of electrical components within the subsystem. The method comprises monitoring (145) the voltage of the subsystem in the first phase, determining a first rate of change from the monitored voltage in the first phase, detecting at least one instance of switching based on the first rate of change, determining an electrical operating time of the circuit breaker based on the detected at least one instance of switching and an instance at which a command for switching was provided to the circuit breaker.

The present invention provides a method of determining an electrical operating time of a circuit breaker (140) in a multiphase electrical system having a subsystem (160) at an electric potential resulting from electrical characteristics of electrical components within the subsystem. The method comprises monitoring (145) the voltage of the subsystem in the first phase, determining a first rate of change from the monitored voltage in the first phase, detecting at least one instance of switching based on the first rate of change, determining an electrical operating time of the circuit breaker based on the detected at least one instance of switching and an instance at which a command for switching was provided to the circuit breaker.

A time-to-voltage converter (TVC) including a 555 timer integrated circuit (IC), and a charging circuit including a constant current source and a capacitor connected in series. The capacitor can be connected to a discharge pin of the 555 timer IC. The TVC can further include a trigger circuit and a reset circuit to receive a start signal and a stop signal, respectively, from an input line, and accordingly generate a trigger signal or a reset signal to trigger or reset the 555 timer IC. A switch can be configured to, under control of an output signal of the 555 timer IC, connect the input line with the reset circuit. A voltage across the capacitor when the 555 timer IC is reset indicates a time interval corresponding to the start and stop signals.

A time-to-voltage converter (TVC) including a 555 timer integrated circuit (IC), and a charging circuit including a constant current source and a capacitor connected in series. The capacitor can be connected to a discharge pin of the 555 timer IC. The TVC can further include a trigger circuit and a reset circuit to receive a start signal and a stop signal, respectively, from an input line, and accordingly generate a trigger signal or a reset signal to trigger or reset the 555 timer IC. A switch can be configured to, under control of an output signal of the 555 timer IC, connect the input line with the reset circuit. A voltage across the capacitor when the 555 timer IC is reset indicates a time interval corresponding to the start and stop signals.

Aspects of the disclosure provide a time-to-voltage converter (TVC). The TVC can include a 555 timer integrated circuit (IC), and a charging circuit including a constant current source and a capacitor connected in series. The capacitor can be connected to a discharge pin of the 555 timer IC. The TVC can further include a trigger circuit and a reset circuit to receive a start signal and a stop signal, respectively, from an input line, and accordingly generate a trigger signal or a reset signal to trigger or reset the 555 timer IC. A switch can be configured to, under control of an output signal of the 555 timer IC, connect the input line with the reset circuit. A voltage across the capacitor when the 555 timer IC is reset indicates a time interval corresponding to the start and stop signals.

Aspects of the disclosure provide a time-to-voltage converter (TVC). The TVC can include a 555 timer integrated circuit (IC), and a charging circuit including a constant current source and a capacitor connected in series. The capacitor can be connected to a discharge pin of the 555 timer IC. The TVC can further include a trigger circuit and a reset circuit to receive a start signal and a stop signal, respectively, from an input line, and accordingly generate a trigger signal or a reset signal to trigger or reset the 555 timer IC. A switch can be configured to, under control of an output signal of the 555 timer IC, connect the input line with the reset circuit. A voltage across the capacitor when the 555 timer IC is reset indicates a time interval corresponding to the start and stop signals.

Embodiments of a constant-on-time pulse generator circuit for a DC-DC converter, a pulse width calibration circuit for a DC-DC converter, and a method for operating a constant-on-time pulse generator circuit for a DC-DC converter are disclosed. In an embodiment, a constant-on-time pulse generator circuit for a DC-DC converter includes serially connected digital buffers and a latch circuit having a set terminal, a reset terminal, and an output terminal. The set terminal and the reset terminal are coupled to the serially connected digital buffers. The latch circuit is configured to output a pulse signal with a constant pulse width through the output terminal.

Systems and methods for detecting the failure of a precision time source using an independent time source are disclosed. Additionally, detecting the failure of a GNSS based precision time source based on a calculated location of a GNSS receiver is disclosed. Moreover, the system may be further configured to distribute a time derived from the precision time source as a precision time reference to time dependent devices. In the event of a failure of the precision time source, the system may be configured to distribute a time derived from a second precision time source as the precision time signal during a holdover period.