Methods and apparatus for resistive voltage sensing in an isolated power distribution unit

摘要

Methods and apparatus provide for a primary side circuit including one or more voltage nodes; and a monitoring circuit operating to monitor one or more parameters of the primary side circuit, and including at least one sensing circuit and at least one processing circuit within a secondary side circuit, where the sensing circuit includes a resistor network having an input for receiving a first sensed voltage from a first of the voltage nodes of the primary side circuit, traversing an isolation boundary between the primary side circuit and the secondary side circuit while adhering to a safety specification, which includes a primary-secondary isolation requirement, and having an output for providing a first modified sensed voltage to the processing circuit.

主权项

1. An apparatus, comprising:
a primary side circuit including one or more voltage nodes; a secondary side circuit including at least one processing circuit; and a resistor network having an input for receiving a first sensed voltage from a first of the one or more voltage nodes of the primary side circuit, traversing an isolation boundary between the primary side circuit and the secondary side circuit while adhering to a safety specification which includes a primary-secondary isolation requirement, and having an output for providing a first modified sensed voltage to the processing circuit; wherein the resistor network includes: a plurality of series-coupled resistors, which are connected at one end to the first voltage node of the primary side circuit, and are connected at an opposite end to a junction node; a shunt resistance coupled from the junction node to a reference potential; the output providing the first modified sensed voltage to the processing circuit is at least one of taken from, and derived from, a voltage at the junction node; wherein: the first voltage node of the primary side circuit exhibits a single ended alternating current (AC) voltage potential with respect to the reference potential; the apparatus further includes a switching circuit including an input terminal coupled to the junction node and an output terminal, which pulses in response to the AC potential at the input terminal; and the output providing the first modified sensed voltage to the processing circuit is a single ended pulsed voltage taken from the output terminal of the switching circuit with respect to the reference potential.