System and method for supplying power to a load using deep-sleep-mode power supplies

A method of supplying power to a load, comprising:

• providing plural power supplies, each having an input converter, an output converter and a standby converter, and each capable of operating in an online mode in which the input, output and standby converters are all enabled for switching, and a deep sleep mode in which the input, output and standby converters are all disabled from switching, and each comprising mode control circuitry configured to change the mode of the power supplies;
• providing operating power to the load from the output converters of a first set of the power supplies that are in the online mode;
• keeping a second set of the power supplies in the deep sleep mode;
• providing power to the mode control circuitry of each of the power supplies in the second set from the standby converters of the first set of power supplies, wherein standby power outputs of all of the standby converters are connected together;
• and
• changing the mode of the power supplies from the online mode to the deep sleep mode and vice versa, such that
• each of the power supplies is configured to transition back and forth between the deep sleep mode and the online mode by passing through a standby mode in which the standby converters of the power supplies are enabled for switching but the input and output converters of the power supplies are disabled from switching.

A system, comprising:

• plural power supplies, each having an input converter, an output converter and a standby converter, and each capable of operating in an online mode in which the input, output and standby converters are all enabled for switching, and a deep sleep mode in which the input, output and standby converters are all disabled from switching;
• a system controller to place a first set of the plural power supplies in the online mode such that its output converters of the first set supply power to the load, and
• a second set of the plural power supplies in the deep sleep mode while the load is operating and the power supplies in the first set are supplying power to the load;
• mode control circuitry in each of the plural power supplies for changing the mode of the power supplies responsive to a communication in a communication bus;
• wherein:
• standby power outputs of all of the standby converters are connected together;
• the standby power outputs of the power supplies in the first set provide power to the mode control circuitry of each of the power supplies in the second set;
• and
• the mode control circuitry achieves mode control by toggling at least one enable or reset signal connected to a converter controller;
• and
• an input converter controller, an output converter controller and a standby converter controller;
• wherein:
• the input converter controller and the output converter controller are powered by at least one of a primary and a secondary bias output of the standby converter;
• and
• the standby converter controller is powered by a rectified DC voltage that is generated directly from an AC mains input to the power supplies.