Systems, methods and devices for power control in mass storage devices

#Aspects of the present invention relate to power monitoring and control features that can be particularly useful for data storage applications in which power draw is an important issue.

#Electronic data storage devices allow the storage and retrieval of data accessed under the control of electrical signaling. Many different recording mediums exist for storing the data, each having different characteristics and parameters. Memories used in data storage devices can be classified into categories including volatile memories and nonvolatile memories. Nonvolatile memories, e.g., those using magnetic recording mediums or floating-gate transistors, maintain stored data in the absence of electrical power. Volatile memory, such as Dynamic-Random-Access-Memory (DRAM) or Static-Random-Access-Memory (SRAM), loses stored data when electrical power is removed.

#Magnetic-based memory devices store data by magnetizing a magnetic recording medium in a particular orientation. Data is read by passing a sensor over the magnetized areas to detect the orientation of the stored magnetic fields. A common format for magnetic recording mediums uses rotating magnetic platters and read-write heads positioned to read or write to the platters as they rotate. Magnetic recording mediums have the advantage of being non-volatile due to the use of a magnetized medium, which does not require electrical power to maintain stored-data integrity.

#The invention may be more completely understood in consideration of the detailed description of various embodiments of the invention that follows in connection with the accompanying drawings as follows:

#FIG. 1 shows a system for operating power-related functions, including backup power functions, of a data storage device, according to an example embodiment of the present invention;

#FIG. 2 shows a data storage device and system, according to an example embodiment of the present invention; and

#While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

#Aspects of the present invention are believed to be useful for monitoring and controlling capacitive energy storage circuits, and such circuits as implemented with data storage devices, circuits and systems. A particular application of the present invention relates to solid state devices (SSDs) that provide nonvolatile memory storage functions. While the present invention is not necessarily limited to such applications, various aspects of the invention may be appreciated through a discussion of various examples using this context.

#According to an example embodiment of the present invention, power supplied to an energy storage circuit in a startup condition is controlled in response to power usage by the energy storage circuit and/or other circuits, to limit the current drawn by the energy storage circuit. In some instances, this control is effected by variably controlling the voltage of the power supplied to charge the energy storage circuit, to limit the current draw from the power supply. Feedback is used in real-time and/or as a predictive control to control the energy storage circuit charging during startup and, where appropriate, during other conditions and/or to control power supplied to other circuits.