A system and method is provided for using a serial bus to communicate (either
passively
or actively) with a point-of-load ("POL") regulator. Specifically, a power supply
controller ("controller") communicates with at least one POL regulators by writing
and/or reading data (either synchronously or asynchronous) over a unidirectional
or bi-directional serial bus. In one embodiment of the present invention, the controller
is adapted to write initial-configuration data (e.g., output voltage set-point,
current limit set-point, etc.) to at least one POL regulator via the serial bus.
At least a portion of the initial-configuration data is then used by the POL regulator
to produce a particular output. In another embodiment of the invention, each POL
regulator includes at least one register for maintaining POL information, such
as unique identification information, fault protection information, output voltage
set-point data, current limit set-point data, etc. The controller is then adapted
to monitor and retrieve this information (i.e., fault-monitoring data) via the
serial bus while the POL regulators are operating.