Methods and circuits for power management of a memory module
AssigneeRambus Inc.
InventorsPanduka Wijetunga, Aws Shallal, Joey M. Esteves
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Abstract
A power-management integrated circuit (PMIC) is installed on a memory module to optimize power use among a collection of memory devices. The PMIC includes external power-supply nodes that receive relatively high and low supply voltages. Depending on availability, the PMIC uses one or both of these supply voltages to generate a managed supply voltage for powering the memory devices. The PMIC selects between operational modes for improved efficiency in dependence upon the availability of one or both externally provided supply voltages.
Claims20
A power-management integrated circuit (PMIC) supporting a first conversion-efficiency mode and a second conversion-efficiency mode, the PMIC comprising:
- a first external input node to receive a first external supply voltage in the first and second conversion-efficiency modes;
- a second external input node to receive a second external supply voltage in the first conversion-efficiency mode, the second external supply voltage absent from the second external input node in the second conversion-efficiency mode;
- and
- an internal power supply coupled to the first and second external input nodes and including an internal supply node to provide an internal supply voltage, the internal power supply to provide the internal supply voltage from the second external supply voltage in the first conversion-efficiency mode and to derive the internal supply voltage from the first external supply voltage in the second conversion-efficiency mode.
A memory module comprising:
- a wiring board;
- memory devices mounted to the wiring board, each memory device having a memory-device power terminal;
- and
- a power-management integrated circuit (PMIC) mounted to the wiring board, the PMIC having:
- a first external input node to receive a first external supply voltage in first and second conversion-efficiency modes;
- a second external input node to receive a second external supply voltage in the first conversion-efficiency mode, the second external supply voltage absent from the second external input node in the second conversion-efficiency mode;
- an internal power supply coupled to the first and second external input nodes and including an internal supply node to provide an internal supply voltage, the internal power supply to provide the internal supply voltage from second external supply voltage in the first conversion-efficiency mode and to derive the internal supply voltage from the first external supply voltage in the second conversion-efficiency mode;
- and
- a voltage converter to produce a third external supply voltage from the first external supply voltage and the internal supply voltage in both the first and second conversion-efficiency modes;
- and
- traces on the wiring board to convey the third external supply voltage from the voltage converter to the memory-device power terminals.
A method of supplying power to memory devices on a memory module, the method comprising:
- receiving a first external supply voltage;
- distinguishing between a presence of a second external supply voltage and an absence of the second external supply voltage;
- in the presence of the second external supply voltage, deriving a third supply voltage from the second external supply voltage and the first external supply voltage;
- in the absence of the second external supply voltage, deriving the third supply voltage from the first external supply voltage;
- and
- distributing the third supply voltage to the memory devices.
Dependencies are inferred from the claim text.