Sharing redundant regulator phases within a phase-redundant voltage regulator apparatus

A phase-redundant voltage regulator apparatus comprising:

• a plurality of regulator phases, each including a regulator electrically coupled to receive, at a regulator input, an input voltage and provide, at a regulator output, a respective output voltage;
• a set of phase groups of the plurality of regulator phases including a first and a second phase group, each phase group including;
• a common regulator input electrically interconnected to regulator inputs of regulators of each phase group;
• a common regulator output electrically interconnected to regulator outputs of regulators of each phase group;
• at least one redundant regulator phase, and
• a multi-phase controller (MPC) electrically coupled to each regulator phase of each phase group, the MPC configured to transfer, to control logic, phase fault signals and a shared current (Ishare) phase control signal received from each regulator phase of a respective phase group;
• a set of spare regulator phases of the plurality of regulator phases including a first and a second spare regulator phase, each spare regulator phase including:
• a secondary output ORing field-effect transistor (FET) electrically coupled between each regulator output and a secondary output of each spare regulator, phase,
• a second comparator having inputs electrically connected to a source terminal and to a drain terminal of the secondary output ° Ring FET, the second comparator further having an output electrically connected to a gate terminal of the secondary output ORing FET, the second comparator configured to, in conjunction with the secondary output ORing FET, limit current flow into the secondary output of each spare regulator phase,
• a first output switching FET electrically connected and configured to, in response to a first phase enable signal, electrically couple each regulator output of each spare regulator phase to a first common regulator output,
• a second output switching FET connected and configured to, in response to a second phase enable signal, electrically couple each regulator output of each spare regulator phase to a second common regulator output;
• and
• control logic, electrically connected to:
• MPCs of each phase group of the set of phase groups, the control logic configured to receive Ishare phase control signals from, and exchange phase fault signals with the MPCs, and
• spare regulator phases of the set of spare regulator phases, the control logic configured to assert phase enable signals to, transfer Ishare phase control signals to, and receive phase fault signals from the spare regulator phases;
• the control logic configured to, in response to a failed regulator phase, receive a phase fault signal from an MPC and electrically interconnect one of the spare regulator phases of the set of spare regulator phases to a phase group that includes the failed regulator phase.

A method for sharing a set of redundant spare regulator phases between phase groups of regulator phases, the method comprising using control logic configured to, in response to monitoring phase fault signals received from the phase groups:

• assert, to a first spare regulator phase of the set of redundant spare regulator phases, in response to detecting a phase single-fault signal from a first phase group, a phase enable signal that electrically couples an output of the first spare regulator phase to a common regulator output of the first phase group;
• send, to the first spare regulator phase, shared current (ISHARE) phase control signals received from a multi-phase controller (MPC) of the first phase group;
• electrically connect a phase fault signal from the first spare regulator phase to the MPC of the first phase group;
• discontinue, in response to detecting the phase single-fault signal from the first phase group, monitoring the phase single-fault signal;
• store, into a non-volatile memory within the control logic, an association between the first spare regulator phase and the common regulator output of the first phase group;
• assert, to a second spare regulator phase of the set of redundant spare regulator phases, in response to detecting an additional phase fault signal from a supplementary phase group, a phase enable signal that electrically couples an output of the second spare regulator phase to a common regulator output of the supplementary phase group;
• send, to the second spare regulator phase, an ISHARE phase control signal received from an MPC of the supplementary phase group;
• electrically connect a phase fault signal from the second spare regulator phase to the MPC of the supplementary phase group;
• discontinue, in response to detecting the additional phase fault signal from the supplementary phase group, monitoring the additional phase fault signal;
• store, into the non-volatile memory, an association between the second spare regulator phase and the common regulator output of the supplementary phase group;
• and
• send, in response to outputs of all of the redundant spare regulator phases being electrically coupled to common regulator outputs of the phase groups, a system notification requesting a regulator replacement operation.