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

• US 10,606,295 B1
• Filed: 03/26/2019
• Issued: 03/31/2020
• Est. Priority Date: 03/26/2019
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Miller, Michael Lee, Swenson, Eric B., Egan, Patrick
• Primary Examiner(s): Nguyen, Matthew V
• Application Number:
  US16/364,748
• Time in Patent Office: 371 Days
• CPC Class Codes: G05F 1/571 with overvoltage detector
• CPC Class Codes: G05F 1/573 with overcurrent detector
• CPC Class Codes: G05F 1/575 characterised by the feedback circuit
• CPC Class Codes: G05F 1/613 using semiconductor devices in parallel with the load as final control devices G05F1/461 takes precedence
• CPC Class Codes: G05F 1/62 using bucking or boosting dc sources
• CPC Class Codes: H02M 1/32 Means for protecting converters other than automatic disconnection
• CPC Class Codes: H02M 1/325 with means for allowing continuous operation despite a fault, i.e. fault tolerant converters
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: H02M 3/1584 with a plurality of power processing stages connected in parallel

Abstract

A phase-redundant voltage regulator apparatus includes groups of regulator phases, each having a multi-phase controller (MPC) connected to each regulator phase. The MPC transfers, to control logic, phase fault signals and a pulse-width modulation (PWM) phase control signal received from the regulator phases of a phase group. Spare regulator phases include output ORing devices to limit current flow into spare regulator phase outputs. Output switching devices are configured to electrically couple spare regulator phase outputs to a common regulator output. Control logic is connected to the phase groups MPC and asserts phase enable signals to, transfers PWM phase control signals to, and receives phase fault signals from the spare regulator phases. The control logic electrically interconnects a spare regulator phase to a phase group including a failed regulator phase in response to receiving a phase fault signal from an MPC.

Claims

1. 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 the phase group;

a common regulator output electrically interconnected to regulator outputs of regulators of the phase group;

at least one redundant regulator phase;

a multi-phase controller (MPC) electrically coupled to each regulator phase of the phase group, the MPC configured to transfer, to control logic, phase fault signals and a pulse-width modulation (PWM) phase control signal received from each regulator phase of a respective phase group; and

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 device electrically coupled and configured to limit current flow into a secondary output of the spare regulator phase;

a first output switching device configured to, in response to a first phase enable signal, electrically couple the regulator output of the spare regulator phase to a first common regulator output; and

a second output switching device configured to, in response to a second phase enable signal, electrically couple the regulator output of the 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 PWM 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 PWM phase control signals to, and receive phase fault signals from the spare regulator phases;

the control logic configured to, in response to receiving a phase fault signal from an MPC, electrically interconnect a spare regulator phase to a phase group that includes a failed regulator phase.

2. The phase-redundant voltage regulator apparatus of claim 1, each regulator phase of the plurality of regulator phases further including:

a phase-redundant controller (PRC) configured to monitor current at the regulator input and further configured to monitor current and voltage at the regulator output;

an output ORing device configured to limit current flow into a primary output of a respective regulator phase; and

an input protection device configured to provide, in response to a control signal from the PRC, input overcurrent protection and output overvoltage protection to the respective regulator phase.

3. The phase-redundant voltage regulator apparatus of claim 1, wherein the MPC of each phase group is further configured to:

receive a feedback output voltage and receive a respective detected current signal from each regulator phase of the phase group;

generate PWM control signals to sequentially activate each regulator phase of the phase group for predetermined periods of time, the PWM control signals managing controlled current-sharing between phases; and

maintain, following a failure of one or more regulator phase of the phase group, current-sharing between all active regulator phases of the phase group.

4. The phase-redundant voltage regulator apparatus of claim 1, wherein each PWM control signal is a digital signal that represents, through a series of pulse widths, a duty cycle/activation time of at least one regulator phase.

5. The phase-redundant voltage regulator apparatus of claim 1, wherein the output ORing device and the secondary output ORing device are each selected from the group consisting of:

an N-channel field-effect transistor (NFET), a P-channel field-effect transistor (PFET), an NPN transistor, and a PNP transistor.

6. The phase-redundant voltage regulator apparatus of claim 1, wherein a regulator serial interface of an MPC is coupled to a system control function through a serial control bus selected from the group consisting of:

an Serial Peripheral Interface (SPI) interface, a Power Management Bus (PMBus) interface, and an Inter-Integrated Circuit (I²C) interface.

7. The phase-redundant voltage regulator apparatus of claim 1, wherein the first phase group of the set of phase groups is configured to maintain current sharing.

8. 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 the phase group;

a common regulator output electrically interconnected to regulator outputs of regulators of the phase group; and

at least one redundant regulator phase; and

a multi-phase controller (MPC) electrically coupled to each regulator phase of the phase group, the MPC configured to transfer, to control logic, phase fault signals and a pulse-width modulation (PWM) phase control signal received from each regulator phase of a respective phase group; and

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 the regulator output and a secondary output of the spare regulator;

a second comparator having inputs electrically connected to a source terminal and to a drain terminal of the secondary output ORing 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 the spare regulator phase;

a first output switching FET electrically connected and configured to, in response to a first phase enable signal, electrically couple the regulator output of the 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 the regulator output of the 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 PWM 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 PWM phase control signals to, and receive phase fault signals from the spare regulator phases;

the control logic configured to, in response to receiving a phase fault signal from an MPC, electrically interconnect a spare regulator phase to a phase group that includes a failed regulator phase.

9. The phase-redundant voltage regulator apparatus of claim 8, each regulator phase of the plurality of regulator phases further including:

a phase-redundant controller (PRC) configured to monitor current at the regulator input and further configured to monitor current and voltage at the regulator output;

an output ORing FET electrically coupled between a primary output of the regulator and the common regulator output;

a first comparator having inputs electrically connected to a source terminal and to a drain terminal of the output ORing FET, the first comparator further having an output electrically connected to a gate terminal of the output ORing FET, the comparator configured to, in conjunction with the output ORing FET, limit current flow into the primary output of a respective regulator phase;

an input protection FET coupled between the common regulator input and a regulator input of the regulator; and

a latch having an output electrically connected to a gate terminal of the input protection FET, the latch configured to, in conjunction with the input protection FET, provide input overcurrent protection and output overvoltage protection to the respective regulator phase.

10. The phase-redundant voltage regulator apparatus of claim 9, wherein the MPC of each phase group is further configured to:

receive a feedback output voltage and receive a respective detected current signal from each regulator phase of the phase group;

generate PWM control signals to sequentially activate each regulator phase of the phase group for predetermined periods of time, the PWM control signals managing controlled current-sharing between phases; and

maintain, following a failure of one or more regulator phase of the phase group, current-sharing between all active regulator phases of the phase group.

11. The phase-redundant voltage regulator apparatus of claim 8, wherein each PWM control signal is a digital signal that represents, through a series of pulse widths, a duty cycle/activation time of at least one regulator phase.

12. The phase-redundant voltage regulator apparatus of claim 8, wherein a regulator serial interface of an MPC is coupled to a system control function through a serial control bus selected from the group consisting of:

an Serial Peripheral Interface (SPI) interface, a Power Management Bus (PMBus) interface, and an Inter-Integrated Circuit (I²C) interface.

13. The phase-redundant voltage regulator apparatus of claim 8, wherein the first phase group of the set of phase groups is configured to maintain current sharing.

14. 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, a pulse-width modulation (PWM) phase control signal 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, a PWM 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.

15. The method of claim 14, wherein the supplementary phase group is selected from the group consisting of:

a first phase group, and a second phase group.

16. The method of claim 14, wherein a current delivery capacity of each regulator phase within a phase group is specified to result in delivery of a specified cumulative output current of the phase group following a failure of one regulator phase within a phase group.

17. The method of claim 14, wherein a current delivery capacity of each regulator phase within a phase group is specified to result in delivery of a specified cumulative output current of the phase group following a failure of at least two regulator phases within a phase group.

18. The method of claim 14, wherein the first spare regulator phase is configured to output a voltage selected from the group consisting of:

a first voltage, and a second voltage.

19. The method of claim 14, wherein the additional phase fault signal is selected from the group consisting of:

single-fault signal, a double-fault signal, and a spare fault signal.

20. The method of claim 14, wherein the system notification requesting a regulator replacement operation is selected from the group consisting of:

an email message, a text message, a console message, and a voicemail message.