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.