Protective circuitry controls power supply enablement

摘要

A protective circuit compares at least two different signals and asserts a control node toward respective logic states accordingly. At least one of the signals is derived from a voltage on a power rail within a computer or other device. A switching element passes or isolates an enable signal based on the logic state of the control node, enabling or preventing operation of a power supply, accordingly. Central processing units (CPUs) or other elements are protected against electrically caused damage in the event that a fault is detected by the protective circuit.

主权项

1. An electronic circuit, comprising:
voltage divider circuitry configured to derive a check signal from a voltage present at a power rail; pass circuitry configured to couple a source voltage to a power node, the pass circuitry configured to bias a control node toward a first state in accordance with a voltage present at the power node; a comparator configured to drive the control node to a second state in accordance with a comparison of the check signal with a core signal; and a switch configured to selectively couple an enable signal to an output node in accordance with a present state of the control node,
wherein the comparator defines a first comparator and the core signal defines a first core signal, andwherein the electronic circuit further includes a second comparator configured to drive the control node to the second state in accordance with a comparison of the check signal with a second core signal.